Antioxidant for flavoring and food ingredients

Abstract

To provide a method for reducing and preventing and / or suppressing oxidation of a perfume component, a mixed perfume, a mixed body care product, a mixed skin care product, a mixed home case product, essential oil, a food raw material, a mixed food product and a natural extract.SOLUTION: A method includes: a step (a) of adding at least one modifier selected from a group consisting of thiol, a sulfur-containing peptide, a sulfur-containing protein, a phosphorylated ascorbic acid analogue, ascorbic acid ester, ascorbate, oxalic acid monoester, oxalic acid monoester salt, a silane hydride compound, diester of oxaloacetic acid, a salt of diester of oxaloacetic acid, glyoxylic acid and a salt of glyoxylic acid, to a perfume having a first POV level, a body care product and cosmetics; and a step (b) of mixing the modifier with or bringing the modifier into contact with the perfume, the body care product and the cosmetics, in a time enough to reduce the first POV level to a predetermined second low level.SELECTED DRAWING: None

Description

[Technical Field]

[0001] Various embodiments presented herein relate to methods and compositions for reducing, preventing, and / or inhibiting oxidation of perfume ingredients, perfume formulations, body care products, skin care products, home care products, essential oils, food ingredients, food formulations, and natural extracts.

[0002] Background of the Invention Many formulated fragrances, body care products, home care products, perfume ingredients (e.g., essential oils, natural extracts, and synthetic ingredients), and food ingredients (e.g., fats and oils from animal or plant sources and their derivatives, including monoglycerides, diglycerides, lecithin, phosphatidylethanolamine, or other phospholipids, and modified triglycerides) can oxidize, resulting in the formation of chemical species including peroxides, organic hydroperoxides, peroxyhemiacetals, hemiacetals, acetals, or transesterification products. The chemical species formed as a result of oxidation can alter the sensory properties or appearance of the perfume ingredients, formulated fragrances, formulated body care products, formulated skin care products, formulated home care products, essential oils, food ingredients, formulated foods, and natural extracts, or can be harmful, irritating, or allergenic.

[0003] One indicator of the degree of oxidation is the peroxide value (POV), defined as the number of equivalents of oxidizing power per kilogram of material. The POV of formulated fragrances, body care products, and fragrance ingredients is or may be subject to regulatory restrictions due to skin sensitization issues, such as contact dermatitis. For example, an unacceptably high POV could cause a fragrance ingredient to fail quality control testing and thus be considered unusable. In another example, an unacceptably high POV could cause a food ingredient to have an unpleasant rancid odor.

[0004] Therefore, there is a need to reduce the incidence of fragrance ingredients, blended fragrances, blended body care products, blended skin care products, blended home care products, essential oils, food ingredients, blended foods, and natural extracts that fail quality control testing or cause skin irritation by reducing the POV of fragrance ingredients, blended fragrances, blended body care products, blended skin care products, blended home care products, essential oils, food ingredients, blended foods, and natural extracts. Furthermore, there is a need to reduce the incidence of rancidity in food ingredients by reducing the POV of food ingredients.

[0005] Summary of the Invention One aspect presented herein provides the following method: The method reduces the POV of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients; The method includes the steps of adding at least one remediant selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient having a first POV level; mixing at least one modifier into the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; Includes:

[0006] One aspect presented herein provides the following method: The method reduces, prevents, and / or inhibits oxidation of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients; The method comprises the step of adding at least one modifier selected from the group consisting of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters and salts thereof, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient in an amount sufficient to reduce, prevent, and / or inhibit oxidation of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0007] In one aspect, reducing, preventing, and / or inhibiting oxidation increases, enhances, and / or improves the stability and / or shelf life of formulated fragrances, body care products, cosmetics, home care products, perfume ingredients, flavor articles, dietary supplements, or food ingredients.

[0008] One aspect presented herein provides the following method: The method reduces, prevents, or ameliorates skin irritation caused by formulated fragrances, body care products, home care products, cosmetics, or fragrance ingredients in a subject in need of such reduction, prevention, or amelioration of skin irritation; This method is (a) adding at least one modifier selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid to a formulated fragrance, body care product, home care product, cosmetic, or food ingredient having a first POV level; (b) mixing at least one modifier with the formulated fragrance, body care product, home care product, cosmetic, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; wherein the predetermined second lower level is sufficient to reduce, prevent, or ameliorate skin irritation in a subject caused by the formulated fragrance, body care product, home care product, cosmetic, or food ingredient.

[0009] In one aspect, the perfume raw materials are selected from the group consisting of synthetic ingredients, natural products, essential oils, and natural extracts.

[0010] In one embodiment, the body care product is a skin cream.

[0011] In one aspect, the food ingredient is selected from the group consisting of fats, oils, or derivatives thereof.

[0012] In one embodiment, the derivative is selected from the group consisting of monoglycerides, diglycerides, and phospholipids.

[0013] In one embodiment, the phospholipid is selected from the group consisting of lecithin, phosphatidylethanolamine, and modified triglycerides.

[0014] In one aspect, perfume raw materials are processed prior to incorporation into the perfume.

[0015] In one aspect, perfume raw materials are processed after incorporation into the perfume.

[0016] In one aspect, the food ingredient is processed prior to incorporation into the flavor article, dietary supplement.

[0017] In one aspect, the food ingredient is incorporated after incorporation into a flavor article, a dietary supplement.

[0018] In one embodiment, the concentration of the at least one modifier ranges from 0.001 to 10% by weight after addition to the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavored article, dietary supplement, or food ingredient.

[0019] In one embodiment, the perfume raw material is a citrus oil.

[0020] In one embodiment, the food ingredient is an edible oil.

[0021] In one embodiment, the predetermined second lower level is between 5 and 20 mmol / L.

[0022] In one embodiment, the predetermined second lower level is 0 to 6 mmol / L.

[0023] In one embodiment, the method further comprises removing excess at least one modifier from the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient having the predetermined second lower POV level.

[0024] In one embodiment, excess at least one modifier is removed from the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient by liquid-liquid extraction.

[0025] In one aspect, the method further comprises treating the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient to reduce its acidity after removing at least one modifier from the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0026] In one aspect, a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is treated with a carbonate salt to reduce the acidity of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0027] One aspect presented herein provides a composition comprising: (a) a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient; and (b) at least one modifier selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid, wherein the at least one modifier is present in the composition in an amount sufficient to reduce the POV from a first level to a predetermined second, lower level.

[0028] One aspect presented herein provides a composition comprising: (a) an incorporated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient; and (b) at least one modifier selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid, wherein the at least one modifier is present in the composition in an amount sufficient to reduce, prevent, or ameliorate an increase in POV of the incorporated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0029] In one embodiment, at least one modifier is added to a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavored article, dietary supplement, or food ingredient at a concentration ranging from 0.001 to 10% by weight.

[0030] In one embodiment, the perfume raw material is a citrus oil.

[0031] In one embodiment, at least one modifier is present in the composition in an amount sufficient to prevent the predetermined second lower level from changing over time.

[0032] In one embodiment, the concentration of the at least one modifier in the composition ranges from 0.001 to 10% by weight.

[0033] In one embodiment, at least one α-oxocarboxylic acid is added as an organic salt to a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient.

[0034] In one embodiment, at least one α-oxocarboxylic acid is present in the composition as an organic salt.

[0035] In one embodiment, the organic salt is an ammonium salt formed by reacting at least one α-oxocarboxylic acid with a compound selected from the group consisting of 2-(dimethylamino)ethanol, N,N-dimethyldodecylamine, tris[2-(2-(methoxyethoxy)ethyl]amine, and N-methyldiethanolamine.

[0036] In one embodiment, the organic salt is an ammonium salt formed by reacting at least one α-oxocarboxylic acid with a compound selected from the group consisting of N-methyldiethanolamine, N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine, and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol.

[0037] In one embodiment, the salt of the at least one α-oxocarboxylic acid is a salt of ornithine or creatine.

[0038] In one embodiment, the organic salt further comprises citric acid.

[0039] In one embodiment, the organic salt further comprises a polymer selected from the group consisting of gelatin, agarose, alginate, polyacrylamide, acrylate, and combinations thereof.

[0040] In one embodiment, at least one α-oxocarboxylic acid is added to a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient as a salt of a monovalent or divalent cation.

[0041] In one embodiment, the at least one α-oxocarboxylic acid is present in the composition as a salt of a monovalent or divalent cation.

[0042] In one embodiment, the at least one α-oxocarboxylic acid is selected from the group consisting of pyruvic acid, 2-oxovaleric acid, phenylglyoxylic acid, 2-oxobutyric acid, 2-oxo-2-furanacetic acid, oxaloacetic acid, α-ketoglutaric acid, 2-oxopentanedioate, indole-3-pyruvic acid, 2-thiopheneglyoxylic acid, trimethylpyruvic acid, 2-oxoadipic acid, 4-hydroxyphenylpyruvic acid, phenylpyruvic acid, 2-oxooctanoic acid, and mixtures thereof.

[0043] In one embodiment, the thiol is selected from the group consisting of glutathione, N-acetylcysteine ​​methyl ester, and cysteine ​​ethyl ester hydrochloride.

[0044] In one embodiment, the ascorbic acid ester may be ascorbyl palmitate.

[0045] In one embodiment, the ascorbate salt may be triethanolammonium ascorbate.

[0046] In one embodiment, the salt of the diester of oxaloacetic acid may be diethyl oxaloacetate sodium salt.

[0047] In one embodiment, the salt of glyoxylic acid may be triethanolamine glyoxylate.

[0048] The present invention further relates to methods of using hydrolyzable esters of 2-oxoacids and / or oxalic acid to reduce the POV by hydrolysis of the ester moiety, resulting in controlled and / or extended in situ release of the 2-oxoacid, oxalic acid monoester, or oxalic acid.

[0049] In one aspect of the present invention, a method is provided for reducing the POV of a fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient, the method comprising: a. adding at least one hydrolyzable ester of a 2-oxoacid and / or a hydrolyzable ester of oxalic acid to a fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, or food ingredient having a first POV level; b. mixing at least one hydrolyzable ester of a 2-oxoacid and / or a hydrolyzable ester of oxalic acid into a fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; Includes:

[0050] In a further aspect, a method reduces, prevents, or ameliorates skin irritation caused by formulated fragrances, body care products, home care products, cosmetics, or fragrance ingredients in a subject in need thereof, the method comprising: a. adding at least one hydrolyzable ester of a 2-oxoacid and / or a hydrolyzable ester of oxalic acid to a formulated fragrance, body care product, home care product, cosmetic, or fragrance raw material having a first POV level; b. mixing at least one hydrolyzable ester of a 2-oxoacid and / or a hydrolyzable ester of oxalic acid into the formulated fragrance, body care product, home care product, cosmetic, or fragrance ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; wherein the predetermined second lower level is sufficient to reduce, prevent, or ameliorate skin irritation in a subject caused by the formulated fragrance, body care product, home care product, cosmetic, or fragrance ingredient.

[0051] In some embodiments, the at least one hydrolyzable ester of a 2-oxoacid and / or the hydrolyzable ester of oxalic acid is an aryl or alkyl ester. In further embodiments, the at least one hydrolyzable ester of a 2-oxoacid and / or the hydrolyzable ester of oxalic acid is selected from the group consisting of di-n-butyl α-ketoglutarate, di-tert-butyl α-ketoglutarate, dibenzyl α-ketoglutarate, dimethyl oxalate, dibutyl oxalate, diethyl oxalopropionate, diethyl oxalopropionate, diethyl α-ketoglutarate, and combinations thereof.

[0052] In aspects of the invention where the treatment substance is insoluble in the treated material, it may be desirable to coat the treatment substance onto a support material. This support material may be, but is not limited to, glass, metal, ceramic, plastic, or paper. A thickening or gelling agent may help adhere the treatment substance to the support material. If complete dissolution of the treatment material is desired, solubilizing agents or chemical groups may be added or covalently attached to the treatment material to make it more soluble. For example, long alkyl chains may be covalently attached to the treatment chemical moiety to solubilize it in hydrophobic treated materials such as triglycerides.

[0053] In some embodiments, the contact surface area between the treatment material and the material to be treated is maximized, or the treatment material is completely dissolved into the material to be treated. [Brief explanation of the drawings]

[0054] [Figure 1] 1 shows an exemplary proposed reaction of an α-oxocarboxylic acid with an organic hydroperoxide according to certain embodiments presented herein. [Figure 2] 1 shows representative percent reduction in POV for perfume ingredients according to certain embodiments presented herein. [Figure 3] 1 shows a POV of a skin cream according to a method according to certain embodiments presented herein. [Figure 4]1 shows a POV of a skin cream according to a method according to certain embodiments presented herein. [Figure 5] 1 shows the change in POV of a model perfume treated by a method according to certain embodiments presented herein. [Figure 6] 1 shows the change in POV of a model perfume treated by a method according to certain embodiments presented herein. [Figure 7] 1 shows a POV of a liquid soap formulation processed by a method according to certain embodiments presented herein. [Figure 8] 1 shows the percent reduction in POV of liquid soap formulations treated by methods according to certain embodiments presented herein. [Figure 9] 1 shows a POV of a shampoo formulation treated by a method according to certain embodiments presented herein. [Figure 10] 1 shows the percent reduction in POV of shampoo formulations treated by methods according to certain embodiments presented herein. [Figure 11] 1 shows a POV of an all-purpose cleaner spray formulation processed by a method according to certain embodiments presented herein. [Figure 12] 1 shows the percent reduction in POV of an all-purpose cleaner spray formulation treated by a method according to certain embodiments presented herein. [Figure 13] 1 shows a POV of a skin cream formulation processed by a method according to certain embodiments presented herein. [Figure 14] 1 shows the percent reduction in POV of skin cream formulations treated by methods according to certain embodiments presented herein. [Figure 15] 1 shows a POV of an antiperspirant stick formulation treated by a method according to certain embodiments presented herein. [Figure 16] 1 shows the percent reduction in POV for antiperspirant stick formulations treated by methods according to certain embodiments presented herein. [Figure 17]1 shows a linear and / or branched series of at least one α-oxocarboxylic acid attached to a multidentate amine compound by an ionic bond according to one embodiment presented herein. [Figure 18] 1 shows a linear and / or branched series of at least one α-oxocarboxylic acid attached to a multidentate amine compound by an ionic bond according to one embodiment presented herein. [Figure 19] 1 shows a linear and / or branched series of at least one α-oxocarboxylic acid attached to a multidentate amine compound by an ionic bond according to one embodiment presented herein. [Figure 20] 1 shows a linear and / or branched series of at least one α-oxocarboxylic acid attached to a multidentate amine compound by an ionic bond according to one embodiment presented herein. [Figure 21]

[0041] Figure 2 shows the reduction in POV over time observed in mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (90%, NMDEA, CAS No. 105-59-9) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (10%, THED, CAS No. 140 07 8) at a molar ratio of 1:1.8:0.1 by the method described in Example 27. [Figure 22] FIG. 2 shows the POV over time observed for mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (90%, NMDEA, CAS No. 105-59-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (10%, THED, CAS No. 140 07 8) at a molar ratio of 1:1.8:0.1 by the method described in Example 27. [Figure 23]FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (80%, NMDEA, CAS No. 105-59-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140 07-8) at a molar ratio of 1:1.6:0.2 by the method described in Example 27. [Figure 24] FIG. 2 shows the POV over time observed for mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (80%, NMDEA, CAS No. 105-59-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140 07-8) at a molar ratio of 1:1.6:0.2 by the method described in Example 27. [Figure 25] FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (80%, NMDEA, CAS No. 105-59-9), N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (10%, THED, CAS No. 140-07-8), and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (10%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:1.6:0.1:0.067, according to the method described in Example 27. [Figure 26]Figure 2 shows the POV over time observed for mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (80%, NMDEA, CAS No. 105-59-9), N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (10%, THED, CAS No. 140-07-8), and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (10%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:1.6:0.1:0.067 by the method described in Example 27. [Figure 27]

[0041] Figure 27 shows the reduction in POV over time observed in mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (60%, NMDEA, CAS No. 105-59-9), N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140-07-8), and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:1.2:0.2:0.134, according to the method described in Example 27. [Figure 28] Figure 2 shows the POV over time observed for mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (60%, NMDEA, CAS No. 105-59-9), N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140-07-8), and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:1.2:0.2:0.134 by the method described in Example 27. [Figure 29]FIG. 2 shows the reduction in POV over time observed in a mixed citrus oil treated with a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and a diammonium salt made from N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140 07-8) at a 1:1 molar ratio by the method described in Example 27. [Figure 30]

[0033] Figure 2 shows the POV over time observed in mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140 07-8) at a 1:1 molar ratio by the method described in Example 27. [Figure 31] FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:0.8:0.13 by the method described in Example 27. [Figure 32] Figure 2 shows the POV over time observed for mixed citrus oils treated with diammonium salts made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:0.8:0.13 by the method described in Example 27. [Figure 33]

[0033] Figure 2 shows the reduction in POV over time observed in mixed citrus oils treated with a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328 50-7) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151 63-7) at a molar ratio of 1:0.67 by the method described in Example 27. [Figure 34] FIG. 2 shows the POV over time observed in mixed citrus oils treated with a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328 50-7) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151 63-7) at a molar ratio of 1:0.67 by the method described in Example 27. [Figure 35] FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) at a molar ratio of 9:0.67:20, according to the method described in Example 28. [Figure 36] FIG. 2 shows the POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a molar ratio of 9:0.67:20, according to the method described in Example 28. [Figure 37] FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (THED, CAS No. 140-07-8) in a molar ratio of 9:0.67:10, according to the method described in Example 28. [Figure 38] FIG. 2 shows the POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (THED, CAS No. 140-07-8) in a molar ratio of 9:0.67:10, according to the method described in Example 28. [Figure 39] FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:8:1.3, according to the method described in Example 28. [Figure 40] Figure 2 shows the POV over time observed for mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:8:1.3 by the method described in Example 28. [Figure 41]FIG. 2 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:6.7, according to the method described in Example 28. [Figure 42] FIG. 2 shows the POV over time observed for mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:6.7, according to the method described in Example 28. [Figure 43] FIG. 10 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:8:1.3, according to the method described in Example 29. [Figure 44]Figure 2 shows the POV over time observed for mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:8:1.3, according to the method described in Example 29. [Figure 45] FIG. 10 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:6.7, according to the method described in Example 29. [Figure 46] Figure 2 shows the POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:6.7, according to the method described in Example 29. [Figure 47] 1 shows the reduction in POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (99%, AKG, CAS No. 328-50-7) and polyacrylic acid (1%, PAA, CAS No. 9003-01-4) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (THED, CAS No. 140-07-8) in a molar ratio of 9.9:0.2:10, according to the method described in Example 30. [Figure 48]Figure 3 shows the POV over time observed for mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (99%, AKG, CAS No. 328-50-7) and polyacrylic acid (1%, PAA, CAS No. 9003-01-4) in a molar ratio of 9.9:0.2:10 and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (THED, CAS No. 140-07-8) according to the method described in Example 30. [Figure 49] FIG. 1 shows the reduction in POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) at a molar ratio of 9.5:1:6.7, according to the method described in Example 30. [Figure 50] Figure 3 shows the POV over time observed for mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) at a molar ratio of 9.5:1:6.7 and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) according to the method described in Example 30. [Figure 51] 3 shows the reduction in POV over time observed in mixed citrus oils treated with cross-linked diammonium salts made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (95%, THED, CAS No. 140 07-8) and polyethyleneimine (5%, PEI, CAS No. 9002-98-6) in a molar ratio of 9.5:1:9.5:1 by the method described in Example 31. [Figure 52]FIG. 3 shows the POV over time observed for mixed citrus oils treated with cross-linked diammonium salts made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (95%, THED, CAS No. 140 07-8) and polyethyleneimine (5%, PEI, CAS No. 9002-98-6) in a molar ratio of 9.5:1:9.5:1 according to the method described in Example 31. [Figure 53]

[0033] Figure 3 shows the reduction in POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151 63-7) and polyethyleneimine (5%, PEI, CAS No. 9002-98-6) in a molar ratio of 9.5:1:6.3:1 according to the method described in Example 31. [Figure 54] FIG. 3 shows the POV over time observed for mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151 63-7) and polyethyleneimine (5%, PEI, CAS No. 9002-98-6) in a molar ratio of 9.5:1:6.3:1 according to the method described in Example 31. [Figure 55] FIG. 3 shows the reduction in POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and polyethyleneimine (PEI, CAS No. 9002-98-6) at a molar ratio of 9.5:1:20, according to the method described in Example 31. [Figure 56] 3 shows the POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and polyethyleneimine (PEI, CAS No. 9002-98-6) at a molar ratio of 9.5:1:20 by the method described in Example 31. [Figure 57] FIG. 3 shows the reduction in POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyethyleneimine (PEI, CAS No. 9002-98-6) at a molar ratio of 1:2, according to the method described in Example 31. [Figure 58] FIG. 1 shows the POV over time observed in mixed citrus oils treated with a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyethyleneimine (PEI, CAS No. 9002-98-6) at a molar ratio of 1:2, according to the method described in Example 31. [Figure 59] FIG. 3 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and sebacic acid (5%, SA, CAS No. 111-20-6) and N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 9.5:0.5:10, according to the method described in Example 32. [Figure 60] Figure 3 shows the POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and sebacic acid (5%, SA, CAS No. 111-20-6) and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 9.5:0.5:10, according to the method described in Example 32. [Figure 61]FIG. 3 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and sebacic acid (10%, SA, CAS No. 111-20-6) and N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 9:1:10, according to the method described in Example 32. [Figure 62] 3 shows the POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and sebacic acid (10%, SA, CAS No. 111-20-6) and N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 9:1:10, according to the method described in Example 32. [Figure 63] FIG. 3 shows the reduction in POV over time observed in mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (80%, AKG, CAS No. 328-50-7) and sebacic acid (20%, SA, CAS No. 111-20-6) and N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 8:2:10, according to the method described in Example 32. [Figure 64] Figure 3 shows the POV over time observed for mixed citrus oils treated with a crosslinked diammonium salt made from α-ketoglutaric acid (80%, AKG, CAS No. 328-50-7) and sebacic acid (20%, SA, CAS No. 111-20-6) and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 8:2:10, according to the method described in Example 32. [Figure 65] 3 shows the relationship between viscosity and shear rate for at least one selected ammonium salt of an α-oxocarboxylic acid, tested by the method described in Example 33. [Figure 66]3 shows the relationship between viscosity and shear rate for at least one selected ammonium salt of an α-oxocarboxylic acid, tested by the method described in Example 33. [Figure 67] 3 shows the relationship between viscosity and shear rate for at least one selected ammonium salt of an α-oxocarboxylic acid, tested by the method described in Example 33. [Figure 68] 1 shows the reduction in POV over time observed in mixed citrus oils treated with 2-phospho-L-ascorbic acid trisodium salt (Vc-PTNa) according to the method described in Example 39. [Figure 69] 1 shows the POV over time observed in mixed citrus oils treated with 2-phospho-L-ascorbic acid trisodium salt (Vc-PTNa) according to the method described in Example 39. [Figure 70] 1 shows the reduction in POV over time observed in mixed citrus oils treated with L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (Vc-PSeMg) according to the method described in Example 39. [Figure 71] 1 shows the POV over time observed in mixed citrus oils treated with L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (Vc-PSeMg) according to the method described in Example 39. [Figure 72] 1 shows the reduction in POV over time observed in model citrus flavors treated with 2-phospho-L-ascorbic acid trisodium salt (Vc-PTNa) according to the method described in Example 39. [Figure 73] 1 shows the POV over time observed in model citrus flavors treated with 2-phospho-L-ascorbic acid trisodium salt (Vc-PTNa) according to the method described in Example 39. [Figure 74] 1 shows the reduction in POV over time observed in model citrus flavors treated with L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (Vc-PSeMg) according to the method described in Example 39. [Figure 75]1 shows the POV over time observed for model citrus flavors treated with L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (Vc-PSeMg) according to the method described in Example 39. [Figure 76] 1 shows the POV over time observed in mixed citrus oils treated with dimethylethylsilane (DMESi) according to the method described in Example 40. [Figure 77] 1 shows the reduction in POV over time observed in mixed citrus oils treated with dimethylethylsilane (DMESi) according to the method described in Example 40. [Figure 78] 1 shows the POV over time observed in mixed citrus oils treated with pentamethyldisiloxane (PMDSi) according to the method described in Example 40. [Figure 79] 1 shows the reduction in POV over time observed in mixed citrus oils treated with pentamethyldisiloxane (PMDSi) according to the method described in Example 40. [Figure 80] 1 shows the POV over time observed in mixed citrus oils treated with methylhydrogensiloxane polymer (PMHS) according to the method described in Example 40. [Figure 81] 1 shows the reduction in POV over time observed in mixed citrus oils treated with methylhydrogensiloxane polymer (PMHS) according to the method described in Example 40. [Figure 82] 4 shows the POV over time observed for mixed citrus oils treated with methylhydrogensiloxane polymers (PMHS) having an average Mn of 1,700-3,200 according to the method described in Example 40. [Figure 83] 1 shows the reduction in POV over time observed in mixed citrus oils treated with methylhydrogensiloxane polymers (PMHS) having an average Mn of 1,700-3,200 according to the method described in Example 40. [Figure 84] 1 shows the POV over time observed for model citrus flavors treated with dimethylethylsilane (DMESi) according to the method described in Example 40. [Figure 85]1 shows the reduction in POV over time observed in model citrus flavors treated with dimethylethylsilane (DMESi) according to the method described in Example 40. [Figure 86] 1 shows the POV over time observed for model citrus fragrances treated with pentamethyldisiloxane (PMDSi) according to the method described in Example 40. [Figure 87] 1 shows the reduction in POV over time observed in model citrus flavors treated with pentamethyldisiloxane (PMDSi) according to the method described in Example 40. [Figure 88] 1 shows the POV over time observed for model citrus flavors treated with methylhydrogensiloxane polymer (PMHS) according to the method described in Example 40. [Figure 89] 1 shows the reduction in POV over time observed in model citrus flavors treated with methylhydrogensiloxane polymer (PMHS) according to the method described in Example 40. [Figure 90] 1 shows the POV over time observed for a model citrus fragrance treated with a methylhydrogensiloxane polymer (PMHS) having an average Mn of 1,700 to 3,200 by the method described in Example 40. [Figure 91] 1 shows the reduction in POV over time observed in model citrus flavors treated with methylhydrogensiloxane polymers (PMHS) having an average Mn of 1,700-3,200 according to the method described in Example 40. [Figure 92] 4 shows the POV over time observed in mixed citrus oils treated with monobutyl oxalate (2-butoxy-2-oxoacetic acid) according to the method described in Example 42. [Figure 93] 4 shows the reduction in POV over time observed in mixed citrus oils treated with monobutyl oxalate (2-butoxy-2-oxoacetic acid) according to the method described in Example 42. [Figure 94] 4 shows the POV over time observed in mixed citrus oils treated with monobenzyl oxalate (2-(benzyloxy)-2-oxoacetic acid) according to the method described in Example 42. [Figure 95] 4 shows the reduction in POV over time observed in mixed citrus oils treated with monobenzyl oxalate (2-(benzyloxy)-2-oxoacetic acid) according to the method described in Example 42. [Figure 96] 1 shows the observed HPLC peak areas of oxidized limonene samples treated according to the method described in Example 43. [Figure 97] 1 shows a plot of POV versus time for di-n-butyl α-ketoglutarate. [Figure 98] 1 shows a plot of the % POV reduction versus time for di-n-butyl α-ketoglutarate. [Figure 99] 1 shows a plot of POV versus time for di-tert-butyl α-ketoglutarate. [Figure 100] 1 shows a plot of POV versus time for dibenzyl α-ketoglutarate. [Figure 101] 1 shows a plot of POV versus time for dimethyl oxalate. [Figure 102] 1 shows a plot of % POV reduction versus time for dimethyl oxalate. [Figure 103] 1 shows a plot of POV versus time for dibutyl oxalate. [Figure 104] 1 shows a plot of % POV reduction versus time for dibutyl oxalate. [Figure 105] 1 shows a plot of POV versus time for diethyl oxalopropionate. [Figure 106] 1 shows a plot of % POV reduction versus time for diethyl oxalopropionate. [Figure 107] 1 shows a plot of POV versus time for diethyl α-ketoglutarate. [Figure 108] 1 shows a plot of the % reduction in POV of diethyl α-ketoglutarate versus time.

[0055] Detailed Description In the following description, reference is made to specific embodiments that may be implemented, which are presented by way of example. These embodiments are described in detail to enable those skilled in the art to practice the inventions described herein, and it should be understood that other embodiments may be utilized and that logical changes may be made without departing from the scope of the aspects presented herein. Therefore, the following description of exemplary embodiments should not be taken in a limiting sense, and the scope of the various aspects presented herein is defined by the appended claims.

[0056] The Abstract is provided to comply with 37 CFR §1.72(b) to allow the reader to quickly ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

[0057] Many formulated fragrances, body care products, home care products, and fragrance ingredients (e.g., essential oils, natural extracts, and synthetic ingredients) can oxidize to form chemical species including peroxides, organic hydroperoxides, and peroxyhemiacetals. Furthermore, many food ingredients, such as fats and oils or their derivatives, are known to undergo an autoxidation process that results in the formation of intermediate chemical species, glyceride hydroperoxides, which can further decompose into aldehydes and ketones. Without intending to be limited to any particular theory, the autoxidation process may result in the unpleasant and unpalatable rancidity of food ingredients.

[0058] The degree of oxidation is indicated by the peroxide value (POV), which is defined as the number of equivalents of oxidizing power per kilogram of material. The POV of formulated fragrances, body care products, and fragrance ingredients is subject to regulatory restrictions due to skin sensitization issues, such as contact dermatitis. For example, an unacceptably high POV may cause a fragrance ingredient to fail quality control testing and thus be considered unusable. In another example, an unacceptably high POV may cause a food ingredient or formulated food (also referred to herein as a flavor article or dietary supplement) to have an unpleasant rancid taste.

[0059] Skin exposure can be the result of accidental exposure (e.g., hard surface cleaners or hand dish soaps when the user is not wearing gloves when applying the product), or it can be the result of prolonged or intentional exposure (e.g., shampoos, or skin moisturizers).

[0060] As used herein, the term "peroxide value" or "POV" refers to the number of equivalents of oxidizing power per kilogram of material. While not intending to be bound by any particular theory, the POV of a material is determined analytically. The term "POV" does not refer to a compound or group of compounds, but is often used loosely interchangeably with the products of autooxidation within a sample that elicit a response during a POV test. These autooxidation products vary depending on the material being tested. Many classes of compounds produce a response during a POV test, including, but not limited to, organic and inorganic hydroperoxides, organic and inorganic peroxides, peroxyhemiacetals, peroxyhemiketals, and hydrogen peroxide itself.

[0061] An exemplary POV test is the iodine redox titration. All POV-responsive compounds possess the property of being able to oxidize iodide ions to molecular iodine within the time period specified for the test; in fact, the iodide oxidation reaction is the basis of the test. Thus, "POV" is a numerical value that represents the sum of the moles of all iodide-oxidized species in a particular sample.

[0062] For example, limonene and linalool are unsaturated terpenes commonly found as the main components of many essential oils. Both limonene and linalool are easily oxidized by atmospheric oxygen to form hydroperoxides. The hydroperoxides of limonene and linalool are known to be sensitizing, causing contact dermatitis. Therefore, limonene and limonene-containing natural products can only be used as fragrance ingredients if the recommended organic hydroperoxide level is less than 20 mmol / L (or 10 mEq / L). Similarly, essential oils and isolates from the Pinacea family, including the pine (Pinus) and fir (Abies) genera, can only be used as fragrance ingredients if the recommended organic hydroperoxide level is less than 10 mmol / L (or 5 mEQ / L).

[0063] As another example, fats and oils or their derivatives are known to undergo an autoxidation process that leads to unpleasant and unpalatable rancidity. Without intending to be limited to any particular theory, glyceride hydroperoxides are intermediate species in the autoxidation process that are further decomposed to aldehydes and ketones, resulting in the rancidity.

[0064] The POV of a perfume raw material can be determined by any method readily selectable by one of ordinary skill in the art, including, but not limited to, iodometric titration, high performance liquid chromatography, and the like.

[0065] An example of a method for determining the POV of a fragrance raw material is disclosed in Calandra et al., Flavor and Fragr. J. (2015), 30, p 121-130.

[0066] Fragrance raw materials include, but are not limited to, essential oils, natural extracts, and synthetic ingredients.

[0067] The POV of a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient can be determined by any method readily selectable by one of skill in the art, including, but not limited to, iodometric titration, high performance liquid chromatography, and the like.

[0068] An example of a method for determining the POV of a blended fragrance is disclosed in Calandra et al., Flavor and Fragr. J. (2015), 30, p 121-130.

[0069] The POV of a formulated body care product can be determined by any method readily selectable by one of ordinary skill in the art, including, but not limited to, iodometric titration, high performance liquid chromatography, and the like.

[0070] An example of a method for determining the POV of a formulated body care product is disclosed in Calandra et al., Flavour and Fragr. J. (2015), 30, p 121-130.

[0071] Without intending to be limited to any particular theory, the POV of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is reduced by treating the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient with at least one modifier. The at least one modifier reacts with the organic hydroperoxide, thereby consuming the organic hydroperoxide and reducing the oxidative power of the organic hydroperoxide.

[0072] As used herein, the term "modifier" refers to an agent that can reduce the POV of an incorporated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. The POV reduction is achieved by treating the incorporated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient and / or by reducing lipid hydroperoxides formed by autoxidation. Modifiers can also react with and remove rancid aldehydes produced by the decomposition of lipid hydroperoxides.

[0073] For example, the POV of formulated fragrances, body care products, cosmetics, home care products, fragrance raw materials, flavor articles, dietary supplements, or food ingredients can be reduced by treating the formulated fragrances, body care products, cosmetics, home care products, fragrance raw materials, flavor articles, dietary supplements, or food ingredients with α-oxocarboxylic acids. The α-oxocarboxylic acids react with organic hydroperoxides by oxidative decarboxylation, thereby consuming the organic hydroperoxides and reducing their oxidative power. The resulting reaction oxidizes the α-oxocarboxylic acids to carbon dioxide and the corresponding carboxylic acid with one less carbon atom, and reduces the organic hydroperoxide to its corresponding organic alcohol. An exemplary proposed reaction using pyruvic acid as the α-oxocarboxylic acid and limonene hydroperoxide as the organic hydroperoxide is shown in Figure 1.

[0074] Accordingly, one aspect presented herein provides the following method: The method reduces the POV of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients; The method includes the steps of adding at least one modifier selected from the group consisting of an α-oxocarboxylic acid, an organic ammonium salt of an α-oxocarboxylic acid, an inorganic salt of an α-oxocarboxylic acid, a thiol, a sulfur-containing peptide, a sulfur-containing protein, a phosphorylated ascorbic acid analog, an ascorbic acid ester, an ascorbate salt, an oxalic acid monoester, an oxalic acid monoester salt, a silane hydride compound, a diester of oxaloacetic acid, a salt of a diester of oxaloacetic acid, glyoxylic acid, and a salt of glyoxylic acid to a formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient having a first POV level; mixing or contacting at least one modifier with the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; Includes:

[0075] Alternatively, one aspect presented herein provides a method comprising: The method reduces, prevents, and / or inhibits oxidation of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients; The method comprises the step of adding at least one modifier selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient in an amount sufficient to reduce, prevent, and / or inhibit oxidation of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0076] One aspect presented herein provides the following method: The method reduces, prevents, or ameliorates skin irritation caused by formulated fragrances, body care products, home care products, cosmetics, or fragrance ingredients in a subject in need of such reduction, prevention, or amelioration of skin irritation; This method is (a) adding at least one modifier selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid to a formulated fragrance, body care product, home care product, cosmetic, or food ingredient having a first POV level; (b) mixing or contacting at least one modifier with the formulated fragrance, body care product, home care product, cosmetic, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; wherein the predetermined second lower level is sufficient to reduce, prevent, or ameliorate skin irritation in a subject caused by the formulated fragrance, body care product, home care product, cosmetic, or food ingredient.

[0077] Alternatively, one aspect presented herein provides the following method: The method reduces the POV of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients; The method includes the steps of adding at least one α-oxocarboxylic acid to a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient having a first POV level; mixing at least one α-oxocarboxylic acid into the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; Includes:

[0078] Alternatively, one aspect presented herein provides a method comprising: The method reduces, prevents, and / or inhibits oxidation of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients; The method includes adding at least one α-oxocarboxylic acid to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient in an amount sufficient to reduce, prevent, and / or inhibit oxidation of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0079] One aspect presented herein provides the following method: The method reduces, prevents, or ameliorates skin irritation caused by formulated fragrances, body care products, home care products, cosmetics, or fragrance ingredients in a subject in need of such reduction, prevention, or amelioration of skin irritation; This method is (a) adding at least one α-oxocarboxylic acid to a formulated fragrance, body care product, home care product, cosmetic, or food ingredient having a first POV level; (b) mixing or contacting at least one α-oxocarboxylic acid with the formulated fragrance, body care product, home care product, cosmetic, or food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level; wherein the predetermined second lower level is sufficient to reduce, prevent, or ameliorate skin irritation in a subject caused by the formulated fragrance, body care product, home care product, cosmetic, or food ingredient.

[0080] In one embodiment, the method is carried out at room temperature. In one embodiment, the method is carried out at a temperature in the range of -20°C to 78°C.

[0081] In one aspect, the perfume raw materials are selected from the group consisting of synthetic ingredients, natural products, essential oils, and natural extracts.

[0082] In one embodiment, the perfume raw material is a citrus oil.

[0083] In one embodiment, the body care product is a skin cream.

[0084] In one aspect, perfume raw materials are processed prior to incorporation into the perfume.

[0085] In one aspect, perfume raw materials are processed after incorporation into the perfume.

[0086] In one embodiment, the predetermined second lower level is 5 to 20 mmol / L. In another embodiment, the predetermined second lower level is 5 to 19 mmol / L. In another embodiment, the predetermined second lower level is 5 to 18 mmol / L. In another embodiment, the predetermined second lower level is 5 to 17 mmol / L. In another embodiment, the predetermined second lower level is 5 to 16 mmol / L. In another embodiment, the predetermined second lower level is 5 to 15 mmol / L. In another embodiment, the predetermined second lower level is 5 to 14 mmol / L. In another embodiment, the predetermined second lower level is 5 to 13 mmol / L. In another embodiment, the predetermined second lower level is 5 to 12 mmol / L. In another embodiment, the predetermined second lower level is 5 to 11 mmol / L. In another embodiment, the predetermined second lower level is 5 to 10 mmol / L. In another embodiment, the predetermined second lower level is 5-9 mmol / L. In another embodiment, the predetermined second lower level is 5-8 mmol / L. In another embodiment, the predetermined second lower level is 5-7 mmol / L. In another embodiment, the predetermined second lower level is 5-6 mmol / L.

[0087] In one embodiment, the predetermined second lower level is 6 to 20 mmol / L. In another embodiment, the predetermined second lower level is 7 to 20 mmol / L. In another embodiment, the predetermined second lower level is 8 to 20 mmol / L. In another embodiment, the predetermined second lower level is 9 to 20 mmol / L. In another embodiment, the predetermined second lower level is 10 to 20 mmol / L. In another embodiment, the predetermined second lower level is 11 to 20 mmol / L. In another embodiment, the predetermined second lower level is 12 to 20 mmol / L. In another embodiment, the predetermined second lower level is 13 to 20 mmol / L. In another embodiment, the predetermined second lower level is 14 to 20 mmol / L. In another embodiment, the predetermined second lower level is 15 to 20 mmol / L. In another embodiment, the predetermined second lower level is 16 to 20 mmol / L. In another embodiment, the predetermined second lower level is 17-20 mmol / L. In another embodiment, the predetermined second lower level is 18-20 mmol / L. In another embodiment, the predetermined second lower level is 19-20 mmol / L.

[0088] In one embodiment, the predetermined second lower level is 20 mmol / L. In another embodiment, the predetermined second lower level is 19 mmol / L. In another embodiment, the predetermined second lower level is 18 mmol / L. In another embodiment, the predetermined second lower level is 18 mmol / L. In another embodiment, the predetermined second lower level is 17 mmol / L. In another embodiment, the predetermined second lower level is 16 mmol / L. In another embodiment, the predetermined second lower level is 15 mmol / L. In another embodiment, the predetermined second lower level is 14 mmol / L. In another embodiment, the predetermined second lower level is 13 mmol / L. In another embodiment, the predetermined second lower level is 12 mmol / L. In another embodiment, the predetermined second lower level is 11 mmol / L. In another embodiment, the predetermined second lower level is 10 mmol / L. In another embodiment, the predetermined second lower level is 9 mmol / L. In another embodiment, the predetermined second lower level is 8 mmol / L. In another embodiment, the predetermined second lower level is 7 mmol / L. In another embodiment, the predetermined second lower level is 6 mmol / L. In another embodiment, the predetermined second lower level is 5 mmol / L. In another embodiment, the predetermined second lower level is 4 mmol / L. In another embodiment, the predetermined second lower level is 3 mmol / L. In another embodiment, the predetermined second lower level is 2 mmol / L. In another embodiment, the predetermined second lower level is 1 mmol / L. In another embodiment, the predetermined second lower level is less than 1 mmol / L.

[0089] In one embodiment, the predetermined second lower level is a 10% reduction in POV, hi another embodiment, the predetermined second lower level is a 20%, or 30%, or 40%, or 50%, or 60%, or 70%, or 80%, or 90%, or 100% reduction in POV.

[0090] Without intending to be limited to any particular theory, the reduction, prevention, and / or inhibition of oxidation increases, enhances, and / or improves the stability and / or shelf life of formulated fragrances, body care products, cosmetics, home care products, fragrance ingredients, flavor articles, dietary supplements, or food ingredients.

[0091] Without intending to be limited to any particular theory, reducing the POV of a flavor article, dietary supplement, or food ingredient prevents, reduces, or inhibits the formation of intermediate glyceride hydroperoxides in the flavor article, dietary supplement, or food ingredient. Reducing, inhibiting, or preventing the formation of intermediate glyceride hydroperoxides in a flavor article, dietary supplement, or food ingredient can prevent, reduce, or delay the development of rancidity in the flavor article, dietary supplement, or food ingredient.

[0092] Without intending to be limited to any particular theory, the at least one modifier may react with and consume lipid hydroperoxides formed by autoxidation and / or react with and consume rancid aldehydes produced by decomposition of lipid hydroperoxides.

[0093] Although not intending to be limited to any particular theory, it is believed that the reaction between at least one α-oxocarboxylic acid and autoxidized triglyceride occurs via two different and independent pathways. The first pathway is the reductive decarboxylation of lipid hydroperoxides by at least one α-oxocarboxylic acid. As a result, the corresponding lipid alcohol is formed, which reduces the POV (peroxide value). Furthermore, since lipid hydroperoxides can no longer decompose into aldehydes, the further generation of sensory rancidity can be prevented. Although not intending to be limited to any particular theory, it is these aldehydes that are perceived as rancidity, and since lipid hydroperoxides themselves do not have a perceptible odor, they do not directly contribute to the unpleasant rancid aroma.

[0094] Thus, rancidity development is a two-step process involving the autoxidation of unsaturated lipids to odorless lipid hydroperoxides, followed by the decomposition of the lipid hydroperoxides to form rancid aldehydes. Consuming the intermediate lipid hydroperoxides before they decompose to rancid aldehydes can prevent rancidity development.

[0095] The second route is to reduce the concentration of rancid aldehydes. At least one α-oxocarboxylic acid can also react directly with rancid aldehydes to form less malodorous adducts, thereby consuming the aldehydes and reducing their concentration. As a result, the rancidity of the treated oil is reduced, resulting in the improvement of an oil that already has a rancid odor. Treatment of triglycerides with at least one α-oxocarboxylic acid is described in detail in Example 36 below.

[0096] Flavor articles and dietary supplements include, for example, foods (e.g., beverages), sweeteners such as natural or artificial sweeteners, pharmaceutical compositions, dietary supplements, functional foods, dental hygiene compositions, and cosmetics. Flavor articles and dietary supplements may further contain at least one flavor article.

[0097] In some embodiments, the at least one flavor can further modify the taste profile or taste attributes of the flavored article, dietary supplement.

[0098] In some embodiments, flavored goods, dietary supplements are foods including, but not limited to, fruits, vegetables, juices, meat products such as ham, bacon and sausage, egg products, fruit concentrates, gelatin and gelatin-like products such as jams and jellies, preserves, dairy products such as ice cream, sour cream and sorbet, icing, syrups including molasses, corn, wheat, rye, soy, oat, rice and barley products, nuts and nut products, cakes, cookies, candy, gum, fruit flavored drops, and confectioneries such as chocolate, chewing gum, mints, creams, pies and breads.

[0099] In some embodiments, the food product is a beverage, including, but not limited to, juice, juice-containing beverages, coffee, tea, carbonated beverages such as Coke and Pepsi, non-carbonated beverages and other fruit drinks, sports drinks such as Gatorade, and alcoholic beverages such as beer, wine, and liquor.

[0100] Flavor articles, dietary supplements can also include prepared packaged products such as granular flavor mixes that, upon reconstitution with water, provide ingredients for non-carbonated beverages, instant pudding mixes, instant coffee and tea, coffee whiteners, malted milk mixes, pet foods, livestock feed, tobacco, and baking applications such as powdered baking mixes for making bread, cookies, cakes, pancakes, donuts, etc.

[0101] Flavored articles, dietary supplements can also include diet or low-calorie foods and beverages that contain little or no sucrose. Flavored articles, dietary supplements can also include condiments such as herbs, spices and seasonings, flavor enhancers (e.g., monosodium glutamate), diet sweeteners and liquid sweeteners.

[0102] In some embodiments, the flavor article, dietary supplement is a pharmaceutical composition, a health supplement, a functional food, a dental hygiene composition, or a cosmetic.

[0103] Dental hygiene compositions are known in the art and include, but are not limited to, dentifrices, mouthwashes, plaque cleaners, dental floss, tooth pain relievers (e.g., ANBESOL, etc.). In some embodiments, the dental hygiene composition comprises one natural sweetener. In some embodiments, the dental hygiene composition comprises two or more natural sweeteners. In some embodiments, the dental hygiene composition comprises sucrose and corn syrup, or sucrose and aspartame.

[0104] In some embodiments, cosmetics include, but are not limited to, face creams, lipsticks, lip glosses, etc. Other suitable cosmetics for use in the present disclosure include lip balms, such as CHAPSTICK or BURT'S BEESWAX Lip Balm.

[0105] Another aspect presented herein provides a method for extending the shelf life of a food ingredient, the method comprising the steps of adding at least one modifier selected from the group consisting of α-oxocarboxylic acids, organic ammonium salts of α-oxocarboxylic acids, inorganic salts of α-oxocarboxylic acids, thiols, sulfur-containing peptides, sulfur-containing proteins, phosphorylated ascorbic acid analogs, ascorbic acid esters, ascorbate salts, oxalic acid monoesters, oxalic acid monoester salts, silane hydride compounds, diesters of oxaloacetic acid, salts of diesters of oxaloacetic acid, glyoxylic acid, and salts of glyoxylic acid to a food ingredient having a first POV level; and mixing or contacting the at least one modifier with the food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level. Without intending to be limited to any particular theory, reducing the first POV level to a predetermined second lower level prevents, reduces, or inhibits the formation of intermediate glyceride hydroperoxides in the food ingredient, thereby preventing, reducing, or inhibiting the development of rancidity in the food ingredient.

[0106] Another aspect presented herein provides a method for extending the shelf life of a food ingredient, the method comprising adding at least one α-oxocarboxylic acid to a food ingredient having a first POV level and mixing or contacting the at least one α-oxocarboxylic acid with the food ingredient for a time sufficient to reduce the first POV level to a predetermined second, lower level. Without intending to be limited to any particular theory, reducing the first POV level to the predetermined second, lower level prevents, reduces, or inhibits the formation of intermediate glyceride hydroperoxides in the food ingredient, thereby preventing, reducing, or inhibiting the development of rancidity in the food ingredient.

[0107] Without intending to be limited to any particular theory, the food ingredient may be used as a solvent for the flavor ingredient, or the food ingredient may itself be the flavor ingredient.

[0108] Another aspect provided herein provides a method for extending the shelf life of a flavor article, a dietary supplement, comprising the steps of adding an α-oxocarboxylic acid, an organic ammonium salt of an α-oxocarboxylic acid, an inorganic salt of an α-oxocarboxylic acid, a thiol, a sulfur-containing peptide, a sulfur-containing protein, a phosphorylated ascorbic acid analog, an ascorbic acid ester, an ascorbate, an oxalic acid monoester, an oxalic acid monoester salt, a silane hydride compound, a diester of oxaloacetic acid, a salt of a diester of oxaloacetic acid, glyoxylic acid, and a salt of glyoxylic acid to a dietary supplement having a first POV level; and mixing or contacting at least one modifier with the flavor article for a time sufficient to reduce the first POV level to a predetermined second, lower level. Without intending to be limited to any particular theory, reducing the first POV level to a predetermined second lower level prevents, reduces, or inhibits the formation of intermediate glyceride hydroperoxides in the flavor article, dietary supplement, thereby preventing, reducing, or inhibiting the development of rancidity in the flavor article, dietary supplement.

[0109] Another aspect provided herein provides a method for extending the shelf life of a food ingredient, the method comprising adding at least one α-oxocarboxylic acid to a flavor article or dietary supplement having a first POV level, and mixing or contacting the at least one α-oxocarboxylic acid with the flavor article or dietary supplement for a time sufficient to reduce the first POV level to a predetermined second, lower level. Without intending to be limited to any particular theory, reducing the first POV level to the predetermined second, lower level prevents, reduces, or inhibits the formation of intermediate glyceride hydroperoxides in the flavor article or dietary supplement, thereby preventing, reducing, or inhibiting the development of rancidity in the flavor article or dietary supplement.

[0110] In one aspect, the food ingredient is selected from the group consisting of fats, oils, or derivatives thereof. In one aspect, the derivatives are selected from the group consisting of monoglycerides, diglycerides, and phospholipids. In one aspect, the phospholipids are selected from the group consisting of lecithin, phosphatidylethanolamine, and modified triglycerides.

[0111] In one aspect, the food ingredient is processed prior to incorporation into the flavor article, dietary supplement. In another aspect, the food ingredient is incorporated after incorporation into the flavor article, dietary supplement.

[0112] In one embodiment, the food ingredient is an edible oil. Examples of edible oils suitable for processing according to embodiments described herein include, but are not limited to, olive oil, palm oil, soybean oil, canola oil (rapeseed oil), corn oil, peanut oil, other vegetable oils, and animal oils such as butter or lard.

[0113] In one embodiment, the method is carried out at room temperature. In one embodiment, the method is carried out at a temperature ranging from -20°C to 78°C.

[0114] In one embodiment, the predetermined second lower level is 0 to 6 mmol / L. In another embodiment, the predetermined second lower level is 0 to 5 mmol / L. In another embodiment, the predetermined second lower level is 0 to 4 mmol / L. In another embodiment, the predetermined second lower level is 0 to 3 mmol / L. In another embodiment, the predetermined second lower level is 0 to 2 mmol / L. In another embodiment, the predetermined second lower level is 0 to 1 mmol / L.

[0115] In one embodiment, the predetermined second lower level is 1-6 mmol / L. In another embodiment, the predetermined second lower level is 2-5 mmol / L. In another embodiment, the predetermined second lower level is 3-5 mmol / L. In another embodiment, the predetermined second lower level is 4-5 mmol / L.

[0116] In one embodiment, the predetermined second lower level is 5 mmol / L. In another embodiment, the predetermined second lower level is 4 mmol / L. In another embodiment, the predetermined second lower level is 3 mmol / L. In another embodiment, the predetermined second lower level is 2 mmol / L. In another embodiment, the predetermined second lower level is 1 mmol / L. In another embodiment, the predetermined second lower level is 0.9 mmol / L. In another embodiment, the predetermined second lower level is 0.8 mmol / L. In another embodiment, the predetermined second lower level is 0.7 mmol / L. In another embodiment, the predetermined second lower level is 0.6 mmol / L. In another embodiment, the predetermined second lower level is 0.5 mmol / L. In another embodiment, the predetermined second lower level is 0.4 mmol / L. In another embodiment, the predetermined second lower level is 0.3 mmol / L. In another embodiment, the predetermined second lower level is 0.2 mmol / L. In another embodiment, the predetermined second lower level is 0.1 mmol / L. In another embodiment, the predetermined second lower level is 0 mmol / L.

[0117] In one embodiment, the predetermined second lower level is a 10% reduction in POV, hi another embodiment, the predetermined second lower level is a 20%, or 30%, or 40%, or 50%, or 60%, or 70%, or 80%, or 90%, or 100% reduction in POV.

[0118] In one embodiment, at least one modifier has FEMA-GRAS status.

[0119] In one embodiment, the at least one α-oxocarboxylic acid has FEMA-GRAS status. In one embodiment, the at least one α-oxocarboxylic acid is selected from the group consisting of pyruvic acid, 2-oxovaleric acid, phenylglyoxylic acid, 2-oxobutyric acid, 2-oxo-2-furanacetic acid, oxaloacetic acid, α-ketoglutaric acid, 2-oxopentanedioate, indole-3-pyruvic acid, 2-thiopheneglyoxylic acid, trimethylpyruvic acid, 2-oxoadipic acid, 4-hydroxyphenylpyruvic acid, phenylpyruvic acid, 2-oxooctanoic acid, and mixtures thereof.

[0120] As used herein, the term "salt" as applied to anions such as 2-oxoacids, oxalic acid, oxalic acid monoesters, glyoxylic acid, and the like, includes salts of lithium, sodium, potassium, magnesium, calcium, iron, copper, zinc, ammonium cations (NH +(Cation derived from the protonation of organic amines containing N-aryl and / or N-alkyl substituents, including but not limited to N-monoalkyl, N,N-dialkyl, N,N,N-trialkyl, N-monoaryl, N,N-diaryl, N,N,N-triarylamine, or any combination thereof, containing further substituents such as triethanolamine, N-methyldiethanolamine; Cations derived from the complete substitution of amines containing N-aryl and / or N-alkyl substituents, including but not limited to N,N,N,N-tetraalkyl, N,N,N,N-tetraaryl, or any combination thereof, containing further substituents such as tetraethanolamine, N-methyltriethanolamine; Cations derived from amino acids such as arginine, ornithine, or proteins or peptides containing basic amino acids, or metabolites such as creatine, uric acid, etc.; Cations derived from nitrogen-containing polymers, either synthetic or natural, such as chitosan. Nitrogen-containing heterocycles, including nitrogen-containing alkaloids such as caffeine, where the nitrogen is contained within the ring or in a substituent on the ring, or any combination of the above moieties.

[0121] In some embodiments, at least one α-oxocarboxylic acid is added to a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient as a salt, which may be formed by reacting the at least one α-oxocarboxylic acid with an organic base.

[0122] In one embodiment where the at least one α-oxocarboxylic acid is a monoacid, the resulting salt may be a mono-salt. In one embodiment where the at least one α-oxocarboxylic acid is a diacid, the resulting salt may be a mono-salt or a di-salt.

[0123] Examples of suitable organic bases include, but are not limited to, the organic bases described in Examples 7-11 below, polymeric amines, polyethyleneimines, and the like.

[0124] Alternatively, the salt may comprise an anion of at least one α-oxocarboxylic acid and a Na + , K. + , Mg 2+ , and Ca 2+ The compound includes a cation selected from the group consisting of:

[0125] Examples of ammonium salts include those formed by reacting at least one α-oxocarboxylic acid with N-methyldiethanolamine.

[0126] In some embodiments, the molar ratio of the at least one α-oxocarboxylic acid to N-methyldiethanolamine may be 1:2, or 1:1, or 2:1.

[0127] In some embodiments, the ammonium salt of at least one α-oxocarboxylic acid has surfactant properties. Without intending to be limited to any particular theory, surfactant properties typically arise from molecules that contain one or more spatially separated long hydrophobic sections, along with ionic and / or highly polar functional groups within the molecule. When the ammonium salt of at least one α-oxocarboxylic acid is attached with a hydrophobic moiety, such as an alkyl group having a sufficient number of carbons (e.g., C-8 to C-24), the resulting molecule can exhibit surfactant properties.

[0128] Without intending to be limited to any particular theory, the ammonium salt of at least one α-oxocarboxylic acid having surfactant properties or being ionic and highly polar may be useful in a variety of home and body care consumer products that come into contact with the user's skin during use.

[0129] Examples of ammonium salts of at least one α-oxocarboxylic acid having surfactant properties include, but are not limited to, the diammonium salt of α-ketoglutaric acid and N,N-dimethyldodecylamine in a 1:2 molar ratio, and the monoammonium salt of α-ketoglutaric acid and N,N-dimethyldodecylamine in a 1:1 molar ratio.

[0130] In some embodiments, the ammonium salt of at least one α-oxocarboxylic acid has emollient properties. Without intending to be limited to any particular theory, emollient properties typically occur in primarily hydrophobic and inert molecules with low melting points (relative to body temperature) and can act as emollients. Useful emollients have oily or grease-like physical properties and act as softeners and / or moisture barriers when applied to the skin. Although the ammonium salt of at least one α-oxocarboxylic acid described above is ionic and highly polar in nature, if a sufficient amount of hydrophobic moieties can be incorporated into the ammonium salt of at least one α-oxocarboxylic acid, the resulting molecule can exhibit emollient properties.

[0131] One approach is to use an amine with three long hydrophobic or oily substituents as the base component of at least one ammonium salt of an α-oxocarboxylic acid. Such molecules have emollient properties as well as hydroperoxide consumption / POV reduction properties, thus providing additional benefits to the user. These would be useful in a variety of consumer body care products that are placed on the skin during use and left on for extended periods to moisturize, protect, or soften the user's skin.

[0132] An example of an ammonium salt of at least one α-oxocarboxylic acid having emollient properties includes, but is not limited to, the diammonium salt of α-ketoglutaric acid and tris[2-(2-methoxyethoxy)ethyl]amine in a 1:2 molar ratio.

[0133] In some embodiments, at least one α-oxocarboxylic acid may be reacted with N-methyldiethanolamine by dissolving it in a solvent such as acetone and adding N-methyldiethanolamine to the solution. The resulting opaque white emulsion may then be vortexed, during which time the second phase may be combined. The mixture is then placed in a freezer for at least 30 minutes to thicken the lower phase until it becomes a waxy solid. The upper layer, while still cold, can then be easily removed and discarded by decantation. Residual acetone is removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature, resulting in a faintly yellow, highly viscous oil containing the diammonium salt at room temperature.

[0134] Other compounds suitable for forming ammonium salts by reaction with at least one α-oxocarboxylic acid include 2-(dimethylamino)ethanol, and N,N-dimethyldodecylamine.

[0135] In one embodiment, the salt is an ammonium salt formed by reacting an α-oxocarboxylic acid with a compound selected from the group consisting of 2-(dimethylamino)ethanol, N,N-dimethyldodecylamine, tris[2-(2-methoxyethoxy)ethyl]amine, and N-methyldiethanolamine.

[0136] Without intending to be limited to any particular theory, it is believed that the ammonium salt of the at least one α-oxocarboxylic acid can prevent acid-catalyzed chemical reactions that could harm and / or degrade the processed or formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient; alternatively, the ammonium salt of the at least one α-oxocarboxylic acid can improve the solubility of the at least one α-oxocarboxylic acid; or alternatively, the ammonium salt of the at least one α-oxocarboxylic acid can provide an emulsifying effect.

[0137] Without intending to be limited to any particular theory, the salt of at least one α-oxocarboxylic acid can be an emulsifier when added to an aqueous system containing formulated fragrances, body care products, cosmetics, home care products, perfume ingredients, flavor articles, dietary supplements, or food ingredients. Such compositions can be useful in salad dressings, marinades, sauces, and the like.

[0138] In one embodiment, the at least one ammonium salt of an α-oxocarboxylic acid may be further combined with at least one other agent, hi one embodiment, the at least one other agent is chitosan.

[0139] In one embodiment, α-ketoglutaric acid is added to a mixture of palmitic acid and chitosan. Such a composition can be an emulsifier for edible oils in aqueous systems and can be useful in salad dressings, marinades, sauces, etc.

[0140] In one embodiment, the salt of the at least one α-oxocarboxylic acid is an ornithine salt or a creatine salt.

[0141] In one embodiment, the thiol is selected from the group consisting of glutathione, N-acetylcysteine ​​methyl ester, and cysteine ​​ethyl ester hydrochloride.

[0142] In one embodiment, the ascorbic acid ester may be ascorbyl palmitate.

[0143] In one embodiment, the ascorbate salt may be triethanolammonium ascorbate.

[0144] In one embodiment, the salt of the diester of oxaloacetic acid may be diethyl oxaloacetate sodium salt.

[0145] In one embodiment, the salt of glyoxylic acid may be triethanolamine glyoxylate.

[0146] In one embodiment, the time sufficient to reduce the POV to the predetermined second lower level is 30 days, or 29 days, or 28 days, or 27 days, or 26 days, or 25 days, or 24 days, or 23 days, or 22 days, or 21 days, or 20 days, or 19 days, or 18 days, or 17 days, or 16 days, or 15 days, or 14 days, or 13 days, or 12 days, or 11 days, or 10 days, or 9 days, or 8 days, or 7 days, or 6 days, or 5 days, or 4 days, or 3 days, or 2 days, or 1 day.

[0147] In one embodiment, the time sufficient to reduce the POV to the second predetermined lower level is greater than 24 hours. In one embodiment, the time sufficient to reduce the POV to the second predetermined lower level is 48 hours, or 47 hours, or 46 hours, or 45 hours, or 44 hours, or 43 hours, or 42 hours, or 41 hours, or 40 hours, or 39 hours, or 38 hours, or 37 hours, or 36 hours, or 35 hours, or 34 hours, or 33 hours, or 32 hours, or 31 hours, or 30 hours, or 29 hours, or 28 hours, or 27 hours. or 26 hours, or 25 hours, or 24 hours, or 23 hours, or 22 hours, or 21 hours, or 20 hours, or 19 hours, or 18 hours, or 17 hours, or 16 hours, or 15 hours, or 14 hours, or 13 hours, or 12 hours, or 11 hours, or 10 hours, or 9 hours, or 8 hours, or 7 hours, or 6 hours, or 5 hours, or 4 hours, or 3 hours, or 2 hours, or 1 hour.

[0148] In one embodiment, the time sufficient to reduce the POV to the second predetermined lower level is 60 minutes or less, hi one embodiment, the time sufficient to reduce the POV to the second predetermined lower level is 60 minutes, or 50 minutes, or 40 minutes, or 30 minutes, or 20 minutes, or 10 minutes, or 9 minutes, or 8 minutes, or 7 minutes, or 6 minutes, or 5 minutes, or 4 minutes, or 3 minutes, or 2 minutes, or 1 minute.

[0149] Without intending to be limited to any particular theory, the amount of α-oxocarboxylic acid and / or the rate at which the α-oxocarboxylic acid is added to the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is controlled to prevent the accumulation of excess α-oxocarboxylic acid, which could, for example, cause acid-catalyzed spoilage of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0150] The amount of α-oxocarboxylic acid added to the formulated fragrance, body care product, fragrance raw material, flavor article, dietary supplement, or food ingredient depends on several factors, including, but not limited to: the stability of the α-oxocarboxylic acid in solution, the solubility of the α-oxocarboxylic acid in the formulated fragrance, body care product, fragrance raw material, flavor article, dietary supplement, or food ingredient, the pKa of the α-oxocarboxylic acid, the percentage reduction in POV, and the effect of the α-oxocarboxylic acid on the olfactory properties and / or taste of the formulated fragrance, body care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0151] Illustratively, pyruvic acid, phenylpyruvic acid, and 2-oxovaleric acid, which have strong aromas, are used as FEMA-GRAS flavor ingredients. In these embodiments, the inherent odor of the α-oxocarboxylic acids may, for example, alter or be incompatible with the sensory qualities of the blended flavor.

[0152] Instead of using odorless α-oxocarboxylic acids in the embodiments described herein, α-oxocarboxylic acids are also used that are compatible with the fragrance of the perfume and that, when consumed by reaction with hydroperoxide, also release a carboxylic acid that is compatible with the fragrance. Illustratively, indole-3-pyruvic acid can be used to reduce the POV of fragrances that are indole-based in nature (containing noticeable amounts of indole and / or skatole).

[0153] An example of odorless α-oxocarboxylic acid includes α-ketoglutaric acid.Without intending to be limited to any particular theory, compared with odorous α-oxocarboxylic acid, odorless α-oxocarboxylic acid has less effect on the sensory properties of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement or food ingredient, so that the POV of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement or food ingredient can be reduced.

[0154] The solubility of α-oxocarboxylic acids may vary depending on the formulation of the composition containing them. Taking α-ketoglutaric acid as an example, the solubility of α-oxocarboxylic acids may be low in perfume raw materials such as citrus oils. However, when perfume raw materials are added to a hydroalcoholic perfume base (a solution containing 80% to 90% ethanol in water), the solubility of α-oxocarboxylic acids may increase. In these embodiments, if the α-oxocarboxylic acid is a strong acid, the amount of α-oxocarboxylic acid in the hydroalcoholic perfume base solution may need to be limited to prevent changes in the sensory properties of the perfume raw material or the blended perfume due to acid-catalyzed decomposition of the perfume raw material.

[0155] An example of an embodiment in which an α-oxocarboxylic acid may be unstable in solution is oxaloacetic acid, which is unstable in aqueous solution. In these embodiments, oxaloacetic acid decomposes into pyruvic acid and carbon dioxide. In these embodiments, the POV of the formulated fragrance, body care product, fragrance raw material, flavor article, dietary supplement, or food ingredient may be reduced through oxaloacetic acid, pyruvic acid, or a combination thereof.

[0156] In some embodiments, the α-oxocarboxylic acid has low solubility in the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. Illustratively, at the lower solubility limit, the α-oxocarboxylic acid is substantially insoluble in the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. In contrast, at the upper solubility limit, the α-oxocarboxylic acid is completely miscible in the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0157] An example of an embodiment in which the solubility of an α-oxocarboxylic acid in a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is low includes, but is not limited to, pyruvic acid in citrus oil. In these embodiments, the α-oxocarboxylic acid may be added at a concentration exceeding the solubility limit, thus forming a two-phase system in which one phase is composed of the α-oxocarboxylic acid. Without intending to be limited to any particular theory, it is believed that the ingredients of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient may be distributed in the phase composed of the α-oxocarboxylic acid. Exposure of ingredients in formulated fragrances, body care products, cosmetics, home care products, fragrance raw materials, flavor articles, dietary supplements, or food ingredients to a phase consisting of alpha-oxocarboxylic acids can result in chemical changes / damage to acid-sensitive compounds in the formulated fragrances, body care products, cosmetics, home care products, fragrance raw materials, flavor articles, dietary supplements, or food ingredients.

[0158] Illustratively, essential oils are primarily composed of terpene compounds. As a class, terpene compounds generally undergo acid-catalyzed rearrangement. Therefore, when the components of a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient are exposed to a phase consisting of α-oxocarboxylic acids, chemical changes / damage may occur to acid-sensitive compounds in the formulated fragrance, which may result in changes in the sensory properties of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0159] Thus, in some embodiments presented herein, the α-oxocarboxylic acid is added at a rate that minimizes or prevents the formation of a second phase consisting of the α-oxocarboxylic acid. Such an addition rate may be equal to the rate of a chemical reaction that reduces the POV of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. While not intending to be limited to any particular theory, adding the α-oxocarboxylic acid at the same rate as the chemical reaction can prevent the accumulation of the α-oxocarboxylic acid, thereby keeping the volume of the second phase to a minimum, thereby reducing the partitioning of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient into the highly acidic phase consisting of the α-oxocarboxylic acid.

[0160] Alternatively, by effectively dispersing an α-oxocarboxylic acid in a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient, the contact area between the two phases of the two-phase system can be increased, thereby increasing the rate of a chemical reaction that reduces the POV of the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0161] An example of an embodiment in which the α-oxocarboxylic acid is not lowly soluble in a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient includes, but is not limited to, 2-oxovaleric acid. Without intending to be limited to any particular theory, an embodiment in which the α-oxocarboxylic acid is not lowly soluble in a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient may result in the formation of a single phase. Here, the added α-oxocarboxylic acid is soluble in the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient being treated, and thus is immediately diluted upon addition. In this case, if the addition rate is close to the reaction rate, the α-oxocarboxylic acid will also be consumed during addition. This keeps the concentration of the α-oxocarboxylic acid low, minimizing acid-induced changes.

[0162] In another embodiment, the concentration of unreacted α-oxocarboxylic acid is minimized by using a buffer, in which case the α-oxocarboxylic acid exists as a deprotonated anion.

[0163] The anionic form of α-oxocarboxylic acid is less likely to react with hydroperoxides than the protonated acidic form. However, when the acidic form is consumed in a reaction with hydroperoxides, the α-oxocarboxylic acid-base pair equilibrium is quickly reestablished according to the pKa of the α-oxocarboxylic acid, and the anionic form instantly captures a proton from the medium to generate more of the acidic form of α-oxocarboxylic acid, which reacts with hydroperoxides. In this way, the bulk acidity of the medium can be maintained at a moderate pH level that does not cause acid damage to the ingredients of the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient. At the same time, however, the reactive protonated form of α-oxocarboxylic acid is present at a relatively low but constant level, and is quickly replenished as it is consumed from the sink of the relatively inactive anionic form.

[0164] For example, using pyruvic acid for illustrative purposes only, the pKa of pyruvic acid is 2.50, and when a formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient is buffered to a pH of 5.5 (a difference of 3 log units) and the concentration of pyruvate anion is 10 compared to pyruvic acid, 3 (or 1000) times (according to the Henderson-Hasselbalch formula).

[0165] In one embodiment, the concentration of the α-oxocarboxylic acid ranges from 0.001 to 10% by weight after addition to the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient. In one embodiment, the concentration of the α-oxocarboxylic acid is 10% by weight after addition to the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient. or the concentration of the α-oxocarboxylic acid after addition to the formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient is 9 percent by weight, or 8 percent by weight, or 7 percent by weight, or 6 percent by weight, or 5 percent by weight, or 4 percent by weight, or 3 percent by weight, or 2 percent by weight, or 1 percent by weight, or 0.9 percent by weight, or 0.8 percent by weight, or 0.7 percent by weight, or 0.6 percent by weight, or 0.5 percent by weight, or 0.4 percent by weight, or 0.3 percent by weight, or 0.2 percent by weight , or 0.1 weight percent, or 0.09 weight percent, or 0.08 weight percent, or 0.07 weight percent, or 0.06 weight percent, or 0.05 weight percent, or 0.04 weight percent, or 0.03 weight percent, or 0.02 weight percent, or 0.01 weight percent, or 0.009 weight percent, or 0.008 weight percent, or 0.007 weight percent, or 0.006 weight percent, or 0.005 weight percent, or 0.004 weight percent, or 0.003 weight percent, or 0.002 weight percent, or 0.001 weight percent.

[0166] The α-oxocarboxylic acid can be added directly to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient, or the α-oxocarboxylic acid can be diluted before being added to the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. Any diluent used in fragrances can be used. Suitable diluents include, but are not limited to, isopropanol, ethanol, diglyme, triethylene glycol, and the like. The α-oxocarboxylic acid may be diluted with the diluent at a ratio of 1:1, 1:2, 1:3, or 1:4 or greater.

[0167] Without intending to be limited to any particular theory, the selection of diluent can also affect the amount of α-oxocarboxylic acid that can be added to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. Furthermore, the selection of diluent can also affect the rate at which the α-oxocarboxylic acid is added to a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. For example, illustratively, when pyruvic acid is used as the α-oxocarboxylic acid and ethanol is used as the solvent, the pyruvic acid should be added in an amount and / or at a rate that minimizes ester formation with ethanol.

[0168] The α-oxocarboxylic acid can be added to any amount of a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient. For example, the α-oxocarboxylic acid can be added to 1000 ml of formulated fragrance, body care product, fragrance raw material, or 900 ml, or 800 ml, or 700 ml, or 600 ml, or 500 ml, or 400 ml, or 300 ml, or 200 ml, or 100 ml, or 90 ml, or 80 ml, or 70 ml, or 60 ml, or 50 ml, or 40 ml, or 30 ml, or 20 ml, or 10 ml, or 9 ml, or 8 ml, or 7 ml, or 6 ml, or 5 ml, or 4 ml, or 3 ml, or 2 ml, or 1 ml of a formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0169] In one embodiment, the α-oxocarboxylic acid may be added to the formulated fragrance, body care product, cosmetic, home care product, perfume raw material, flavor article, dietary supplement, or food ingredient over 80 minutes, or the α-oxocarboxylic acid may be added to the formulated fragrance, body care product, cosmetic, home care product, perfume raw material, flavor article, dietary supplement, or food ingredient over 70 minutes, or 60 minutes, or 50 minutes, or 40 minutes, or 30 minutes, or 20 minutes, or 10 minutes, or 9 minutes, or 8 minutes, or 7 minutes, or 6 minutes, or 5 minutes, or 4 minutes, or 3 minutes, or 2 minutes, or 1 minute.

[0170] In one embodiment, the α-oxocarboxylic acid is added to the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient at a rate of 0.25 ml per minute. In some embodiments, the addition rate is greater than 0.25 ml per minute. In some embodiments, the addition rate is less than 0.25 ml per minute.

[0171] In some embodiments, the rate at which the α-oxocarboxylic acid is added to the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is constant. In some embodiments, the rate at which the α-oxocarboxylic acid is added to the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is variable. In one embodiment, the α-oxocarboxylic acid is added to the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient at a rate equal to the rate at which the α-oxocarboxylic acid is oxidized. In some embodiments, the rate at which the α-oxocarboxylic acid is oxidized may be determined by measuring the POV of the processed and formulated fragrance, body care product, or fragrance raw material. Referring to Figures 2-4, illustratively, the rate of reduction of the POV may have a first rate that is greater than a second rate. In an exemplary embodiment, the duration of the first rate is less than the duration of the second rate.

[0172] In another embodiment, the α-oxocarboxylic acid may be added, followed by quenching after a period of time. The α-oxocarboxylic acid may be quenched 80 minutes after addition to the substance. Alternatively, the α-oxocarboxylic acid may be quenched 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 minute after addition to the substance.

[0173] In one embodiment, the method further comprises removing excess at least one modifier from the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient having the predetermined second lower POV level.

[0174] In one embodiment, excess at least one modifier is removed from the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient by liquid-liquid extraction.

[0175] In one aspect, the method further comprises treating the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient to reduce its acidity after removing at least one modifier from the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0176] In one embodiment, the method further comprises removing excess α-oxocarboxylic acid from the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient having a predetermined second lower level of POV.

[0177] In one aspect, excess α-oxocarboxylic acid is removed from formulated fragrances, body care products, cosmetics, home care products, perfume ingredients, flavor articles, dietary supplements, or food ingredients by liquid-liquid extraction.

[0178] In one aspect, excess α-oxocarboxylic acid is removed from formulated fragrances, body care products, cosmetics, home care products, perfume ingredients, flavor articles, dietary supplements, or food ingredients by liquid-liquid extraction with water.

[0179] In one embodiment, other by-products of the reaction that reduces the POV of the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient to a predetermined second lower level are also removed by liquid-liquid extraction. All or a portion of the by-products may be removed.

[0180] In one aspect, the method further comprises treating the formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient after removing excess α-oxocarboxylic acid to reduce the acidity of the material. In some aspects, this treatment comprises the addition of a buffering agent, such as, for example, triethanolamine or N-methyldiethanolamine.

[0181] In one embodiment, a material is treated with carbonate to reduce the acidity of a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient.

[0182] In one aspect, a method for reducing the POV of a formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient comprises the steps of: a) introducing a blended fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient into a reaction vessel, wherein the blended fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient is under an inert gas, such as argon; b) introducing the α-oxocarboxylic acid into the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient at a rate of 0.25 ml / min, wherein the α-oxocarboxylic acid is diluted 1:4 with the diluent, and the α-oxocarboxylic acid is constantly stirred while being introduced into the formulated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient; c) introducing water and anhydrous sodium carbonate into the mixture and continuing the reaction until no further CO evolution is visible; d) discarding the aqueous layer, thereby obtaining a formulated fragrance, body care product, cosmetic, home care product, fragrance ingredient, flavor article, dietary supplement, or food ingredient having a predetermined second lower level of POV; Includes:

[0183] Examples of methods according to the above embodiments can be found in Examples 1-4 below.

[0184] In some embodiments, the second phase of α-oxocarboxylic acid in the formulated fragrance, body care product, cosmetic, home care product, perfume raw material, flavor article, dietary supplement, or food ingredient is a "leave-in" composition of α-oxocarboxylic acid. Without intending to be limited to any particular theory, the amount of α-oxocarboxylic acid present in the two phases may be in equilibrium, and a reduction in POV may result in the α-oxocarboxylic acid migrating from the phase consisting of α-oxocarboxylic acid to the phase containing the formulated fragrance, body care product, cosmetic, home care product, perfume raw material, flavor article, dietary supplement, or food ingredient. An example of this embodiment is described in Example 5 below.

[0185] In some embodiments, the "residual" composition of α-oxocarboxylic acid comprises a single-phase composition with formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient. In these embodiments, the composition further comprises a buffer, and the pH is set to maintain a majority of the α-oxocarboxylic acid present in the unprotonated form, which cannot react with species that contribute to the POV of the composition (including peroxides, organic hydroperoxides, and peroxyhemiacetals). Without intending to be limited to any particular theory, it is believed that the amount of α-oxocarboxylic acid present in the unprotonated form is in equilibrium with the amount of α-oxocarboxylic acid present in the protonated form, and that a reduction in the POV may result in the transfer of α-oxocarboxylic acid from the unprotonated form to the protonated form. An example of this embodiment is described in Example 4 below.

[0186] In these instances, the "residual" composition of α-oxocarboxylic acids can reduce the POV over an extended period of time.

[0187] Accordingly, one aspect presented herein provides a composition comprising: (a) a formulated fragrance, body care product, cosmetic, home care product, perfume ingredient, flavor article, dietary supplement, or food ingredient; and (b) an α-oxocarboxylic acid, wherein the α-oxocarboxylic acid is present in the composition in an amount sufficient to reduce the POV from a first level to a predetermined second, lower level.

[0188] In one embodiment, the α-oxocarboxylic acid is present in the composition in an amount sufficient to prevent the predetermined second lower level from changing over time, which may be hours, days, weeks, or longer.

[0189] One aspect presented herein provides a composition comprising: (a) an incorporated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient; and (b) an α-oxocarboxylic acid, wherein the α-oxocarboxylic acid is present in the composition in an amount sufficient to reduce, prevent, or ameliorate an increase in POV of the incorporated fragrance, body care product, cosmetic, home care product, fragrance raw material, flavor article, dietary supplement, or food ingredient.

[0190] In one embodiment, the concentration of the at least one α-oxocarboxylic acid in the composition ranges from 0.001 to 10 weight percent.

[0191] In one embodiment, the thiol is selected from the group consisting of glutathione, N-acetylcysteine ​​methyl ester, and cysteine ​​ethyl ester hydrochloride.

[0192] In one embodiment, the ascorbic acid ester may be ascorbyl palmitate.

[0193] In one embodiment, the ascorbate salt may be triethanolammonium ascorbate.

[0194] In one embodiment, the salt of the diester of oxaloacetic acid may be diethyl oxaloacetate sodium salt.

[0195] In one embodiment, the salt of glyoxylic acid may be triethanolamine glyoxylate.

[0196] In one embodiment, the salt of the at least one α-oxocarboxylic acid is an ornithine salt or a creatine salt.

[0197] In one embodiment, the at least one α-oxocarboxylic acid is selected from the group consisting of pyruvic acid, 2-oxovaleric acid, phenylglyoxylic acid, 2-oxobutyric acid, 2-oxo-2-furanacetic acid, oxaloacetic acid, α-ketoglutaric acid, 2-oxopentanedioate, indole-3-pyruvic acid, 2-thiopheneglyoxylic acid, trimethylpyruvic acid, 2-oxoadipic acid, 4-hydroxyphenylpyruvic acid, phenylpyruvic acid, 2-oxooctanoic acid, and mixtures thereof.

[0198] In one embodiment, the perfume raw material is a citrus oil.

[0199] An example of a composition according to the above embodiment can be found in Example 5 below.

[0200] In some embodiments, the at least one modifier may be applied to, incorporated into, or covalently attached to a solid substrate, and the solid substrate containing the at least one modifier is used to treat a formulated fragrance, body care product, cosmetic, perfume ingredient, flavor article, dietary supplement, or food ingredient.

[0201] In some embodiments, the at least one α-oxocarboxylic acid, or salt thereof, may be applied to, incorporated into, or covalently attached to a solid substrate, and the solid substrate comprising the at least one α-oxocarboxylic acid, or salt thereof, is used to treat a formulated fragrance, body care product, cosmetic, perfume ingredient, flavor article, dietary supplement, or food ingredient.

[0202] The solid support can be any inert, finely divided, or high surface area material. Examples include, but are not limited to, metal, glass, expanded ceramic, plastic, or inorganic solids. Furthermore, the solid support can include the bottom and / or walls of a container that contains a formulated fragrance, body care product, cosmetic, perfume ingredient, flavor article, dietary supplement, or food ingredient.

[0203] In some embodiments, the solid support has a large surface area to volume ratio. Examples of such solid supports include, but are not limited to, steel wool. Examples of compositions processed according to the embodiments using such solid supports can be found in Example 24 below.

[0204] 17 and Examples 27-34 below, in some embodiments, the salt of at least one α-oxocarboxylic acid is insoluble, and the salt comprises a linear series of at least one α-oxocarboxylic acid bound to a multidentate amine compound via an ionic bond. As used herein, the term "multidentate amine compound" refers to an amine compound having two or more free amine groups capable of forming an ionic bond with the carboxyl group of at least one α-oxocarboxylic acid.

[0205] In some embodiments, the linear series includes a "bidentate" amine compound. As used herein, "bidentate amine compound" refers to an amine compound having two free amine groups capable of forming an ionic bond with the carboxyl group of at least one α-oxocarboxylic acid.

[0206] 17 and 18, in some embodiments, branching can be introduced into a linear series of at least one α-oxocarboxylic acid bound to an amine compound by introducing a tridentate amine compound, a bidentate acid, or a mixture thereof. As used herein, the term "tridentate amine compound" refers to an amine compound having three free amine groups capable of forming an ionic bond with the carboxyl group of at least one α-oxocarboxylic acid. As used herein, the term "bidentate acid" refers to an acid having two carboxyl groups capable of forming an ionic bond with the amide group of an amide compound. Examples of tridentate acids include, but are not limited to, citric acid.

[0207] In some embodiments, the at least one α-oxocarboxylic acid is pyruvic acid, 2-oxovaleric acid, phenylglyoxylic acid, 2-oxobutyric acid, 2-oxo-2-furanacetic acid, oxaloacetic acid, α-ketoglutaric acid, 2-oxopentanedioate, indole-3-pyruvic acid, 2-thiopheneglyoxylic acid, trimethylpyruvic acid, 2-oxoadipic acid, 4-hydroxyphenylpyruvic acid, phenylpyruvic acid, 2-oxooctanoic acid, and mixtures thereof.

[0208] In some embodiments, the polydentate amine compound is selected from the group consisting of N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine, 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol, and mixtures thereof.

[0209] Other examples of polydentate amine compounds suitable for use in the present disclosure include amino acids, polyimines, chitosan, and the like.

[0210] Referring to Figures 19 and 20, in some embodiments, the linear and / or branched series of at least one α-oxocarboxylic acid attached to the multidentate amine compound via an ionic bond further comprises polyacrylic acid, polyethyleneimine, or a mixture thereof.

[0211] In some embodiments, the linear and / or branched series may include a multidentate amine compound attached to at least one α-oxocarboxylic acid via an ionic bond with another moiety, such as, for example, a phosphate or sulfate moiety.

[0212] In some embodiments, at least one α-oxocarboxylic acid is incorporated into the aqueous phase of a gel comprising a polymer selected from the group consisting of gelatin, agarose, alginate, polyacrylamide, acrylate, and combinations thereof.

[0213] In some embodiments, the gel may be configured to exclude molecules above or below a certain molecular weight, examples of such configurations include, but are not limited to, the formation of branches configured to act as a size exclusion filter.

[0214] In some embodiments, the at least one α-oxocarboxylic acid further comprises an ammonium salt.

[0215] In some embodiments, the linear and / or branched series of at least one α-oxocarboxylic acid bound to the amine compound via an ionic bond comprises a polymer selected from the group consisting of gelatin, agarose, alginate, polyacrylamide, acrylate, and combinations thereof. In some embodiments, the linear and / or branched series of at least one α-oxocarboxylic acid bound to the amine compound via an ionic bond comprises a network incorporating an aqueous phase. In some embodiments, the aqueous phase may comprise at least one α-oxocarboxylic acid.

[0216] In one aspect, the amine compound may be a multidentate amine compound.

[0217] In some embodiments, the linear and / or branched series of at least one α-oxocarboxylic acid attached to the amine compound via an ionic bond may be configured to exclude molecules above or below a certain molecular weight. Examples of such configurations include, but are not limited to, the formation of branches configured to function as a size exclusion filter.

[0218] In one aspect, the amine compound may be a multidentate amine compound.

[0219] Without intending to be limited to any particular theory, it is believed that the linear and / or branched series of at least one α-oxocarboxylic acid attached to a multidentate amine compound via an ionic bond is insoluble and has increased viscosity, viscoelasticity, or gel-like properties. In some embodiments, the linear and / or branched series of at least one α-oxocarboxylic acid attached to a multidentate amine compound via an ionic bond is water-free.

[0220] In some embodiments, the increased viscosity, viscoelasticity, or gel-like properties of the linear and / or branched series of at least one α-oxocarboxylic acid bound to the multidentate amine compound via an ionic bond may be configured to enhance, improve, or facilitate attachment of the linear and / or branched series of at least one α-oxocarboxylic acid bound to the multidentate amine compound via an ionic bond to a solid substrate.

[0221] Referring to Example 32, in some embodiments, increasing the hydrophobicity of at least one α-oxocarboxylic acid attached to the multidentate amine compound via an ionic bond can enhance the reduction in POV.

[0222] The POV-modifying compounds described herein can be used in combination with known antioxidants. Any antioxidant that is conventionally used and / or suitable for a particular application can be combined with the POV-modifying compounds of the present invention.

[0223] Other antioxidants include, but are not limited to, synthetic compounds such as BHT (butylated hydroxytoluene), BHA (butylated hydroxyanisole), TBHQ (tert-butylhydroquinone), propyl gallate, and antioxidants described in U.S. Patent No. 7,247,658. Naturally derived antioxidants can also be used in combination with the POV modifiers, including, but not limited to, tocopherols, tocotrienols, ascorbic acid, carotenoids, flavonoids, anthocyanins, stilbenoids, isoflavones, and catechins.

[0224] The present invention is best illustrated by, but not limited to, the following examples.

[0225] Example Example 1: Reduction of POV in citrus oils according to one embodiment presented herein using pyruvic acid 50 mL of mixed citrus oils (orange, lemon, lime, mandarin, bergamot, and tangerine) were placed in a 100 ml round-bottom flask at room temperature with a stir bar and argon gas blanket.

[0226] A 4:1 (v / v) isopropanol / pyruvic acid solution was prepared, and 20 mL of this pyruvic acid solution was added dropwise to the stirred citrus oil at a rate of 0.25 mL / min using a syringe pump.

[0227] Once the addition was complete, 10 mL of water and 100 mg of anhydrous sodium carbonate were added to the flask and stirring was maintained. Once visible CO evolution ceased (approximately 2-4 minutes), the aqueous layer was removed with a pipette and discarded. POV measurements were performed on this mixed citrus oil before and after pyruvate treatment.

[0228] The pre-treatment POV was 27.261 mEq / L and the post-treatment POV was 4.786 mEq / L, which was approximately an 82% reduction in POV.

[0229] Example 2: Reduction of POV in limonene using 2-oxovaleric acid according to one embodiment presented herein 10 mL of autoxidized limonene was placed in a 30 mL glass vial at room temperature with a stir bar and argon gas blanket. 100 μL of 2-oxovaleric acid was added. The vial was shaken once and allowed to stand for 50 minutes. No further treatment was performed before the POV test. POV measurements were performed on this limonene before and after 2-oxovaleric acid treatment. The POV before treatment was 65.97 mEq / L, and the POV after treatment was 17.21 mEq / L. This was an approximately 74% reduction in POV.

[0230] Example 3: Reduction of POV in limonene using 2-oxobutyric acid according to one embodiment presented herein 20 mL of autoxidized limonene was placed in a 30 mL glass vial at room temperature with a stir bar and argon gas blanket. 250 μL of 2-oxobutyric acid was added. The vial was shaken once and allowed to settle while monitoring the POV value as a function of time. The collected data is shown in the table below.

[0231] [Table 1]

[0232] The results showed an initial rapid reduction in POV, followed by a slower rate of POV reduction. This may be due to reagent depletion, but this reduction in POV is not sufficient to fully account for all the 2-oxobutyric acid added on a molar basis. Some hydroperoxides may decompose very quickly, while other oxidants may decompose much more slowly. When an additional 500 μL of 2-oxobutyric acid was added and the sample allowed to stand for an additional 24 hours, the measured POV was 8.577 mEq / L (87.1% total reduction).

[0233] Example 4: Reduction of POV in Limonene Using 2-Phenylglyoxylic Acid According to an Embodiment Presented herein 20 mL of autoxidized limonene was placed in a 30 mL glass vial at room temperature with a stir bar and argon gas blanket. 200 mg of phenylglyoxylic acid was added, which dissolved. The vial was shaken once and allowed to settle while monitoring the POV value as a function of time. The collected data is shown in the table below.

[0234] [Table 2]

[0235] Example 5: Reduction of POV in limonene using 2-oxo-2-furanacetic acid according to one embodiment presented herein 20 mL of mixed citrus oil was placed in a 30 mL glass vial at room temperature with a stir bar and argon gas blanket. 400 mg of α-oxo-2-furanacetic acid was added. The vial was shaken once and allowed to settle while monitoring the POV as a function of time. Because the majority of the added α-oxo-2-furanacetic acid did not dissolve, the limited solubility of this acid may function as a controlled-release mechanism. The dissolved α-oxo-2-furanacetic acid is likely consumed by hydroperoxides, dissolving according to its solubility constant. Thus, the undissolved solids act as a sink to maintain a stable, low concentration of dissolved α-oxo-2-furanacetic acid in the mixed citrus oil.

[0236] In this case, the relatively long time between measurements (days instead of minutes) allowed for further oxidation of the untreated blended citrus oil over the course of the experiment. Therefore, the POV of the treated oil was still compared to the POV of the untreated oil, but the measurements of the untreated oil were re-measured at each time point (rather than simply using a single initial value). The collected data are shown in the table below.

[0237] [Table 3]

[0238] Example 6: Reduction of POV in a skin cream formulation according to one embodiment presented herein using 2-oxovaleric acid or phenylglyoxylic acid A skin cream formulation was prepared according to the German Pharmacopoeia DAB 2008 containing 0.5 parts cetylstearyl alcohol, 6.0 parts wool wax alcohol, and 93.5 parts white petrolatum.

[0239] This skin cream was divided into two separate preparations. A highly oxidized limonene sample was added to both preparations, with the first preparation receiving approximately one-third the concentration of oxidized limonene in the second preparation. Analysis of the oxidized limonene sample revealed that it contained a mixture of limonene hydroperoxide isomers.

[0240] The initial POVs of the first and second skin cream formulations were obtained before treatment with 2-oxovaleric acid or phenylglyoxylic acid as follows: 2-oxovaleric acid (second formulation) or phenylglyoxylic acid (first formulation) was thoroughly blended into the skin cream formulation. The POVs of the formulations were measured during the addition of 2-oxovaleric acid. After the addition of 2-oxovaleric acid or phenylglyoxylic acid, the treated formulations were allowed to stand at room temperature. The resulting POV data were corrected for the exact mass of the cream aliquot titrated at each individual time point and normalized as a percentage of the starting POV.

[0241] The second preparation, containing the highest amount of oxidized limonene sample, was treated with approximately 2.3% w / w 2-oxovaleric acid, and the results are shown in Figure 3 below.

[0242] The first preparation, containing the lowest amount of oxidized limonene sample, was treated with approximately 3.9% w / w 2-phenylglyoxylic acid, and the results are shown in Figure 4 below.

[0243] Example 7: Formation of a diammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a molar ratio of 1:2 1.461 g (0.01 mol) of α-ketoglutaric acid was dissolved in 10 mL of anhydrous acetone to obtain a clear solution. This solution was added in one portion to 2.384 g (0.02 mol) of neat NMDEA. The opaque white emulsion was vortexed vigorously for 3-4 minutes, during which time a second phase coalesced. This mixture was placed in a freezer for at least 30 minutes, during which time the lower phase thickened to a waxy solid. While still cold, the upper layer was simply removed by decantation or pipette and discarded. Residual acetone was removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature. This resulted in a clear, pale yellow, highly viscous oil containing the diammonium salt (AKG-DiNMDEA salt) at room temperature.

[0244] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 400 mg (2.0% w / v) of AKG-DiNMDEA salt was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, since sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0245] [Table 4]

[0246] These data show that 24 hours after addition of AKG-DiNMDEA salt, POV was reduced by approximately 94%.

[0247] In addition to the treatments performed on the model fragrances described above, similar experiments were performed on mixed citrus oils. Because mixed citrus oil samples were prepared by combining lime, orange, grapefruit, lemon, mandarin, tangerine, and bergamot oils, it was anticipated that various terpene hydroperoxides would be present in the treated mixtures being tested. Approximately 200 mg (1.0% w / v) of AKG-DiNMDEA salt was added to 20 mL of mixed citrus oil. Even after vigorous mixing, the salt did not appear to be completely dissolved. Nevertheless, POV measurements were performed as a function of time after addition. Untreated mixed citrus oil samples were handled and further tested in the same manner as the treated oils, since sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0248] [Table 5]

[0249] This represents only a moderate to good improvement in the POV status of the oil, with a 59% reduction in POV after more than 1 day of treatment time, which may be due to the low solubility of 2-oxoacid salts in citrus oils.

[0250] Example 8: Formation of a diammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and N,N-dimethyldodecylamine (DiMeC12A, CAS No. 112-18-5) in a molar ratio of 1:2 1.461 g (0.01 mol) of α-ketoglutaric acid was dissolved in 6 mL of anhydrous acetone. This solution was added dropwise over 1-2 minutes with stirring to a separate solution of 4.268 g (0.02 mol) of N,N-dimethyldodecylamine in 6 mL of anhydrous acetone. No visible signs of reaction were observed except that the combined solution warmed to approximately 35-40 °C. The mixture was briefly but vigorously shaken and then chilled in a freezer for 30 minutes. Although no precipitation of the product occurred even at the low temperature, the mixture was shaken again, and the entire amount solidified almost instantly to a solid white waxy material. The solid was warmed to 30-35 °C, allowing the trapped acetone to be removed with a nitrogen stream, followed by treatment in a vacuum oven at room temperature. This yielded a white waxy solid containing the diammonium salt (AKG-DiMeC12A salt).

[0251] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 400 mg (2.0% w / v) of AKG-DiMeC12A salt was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, as sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0252] [Table 6]

[0253] In addition to the treatments performed on the model fragrances described above, similar experiments were performed on mixed citrus oils. The mixed citrus oil samples were prepared by combining lime, orange, grapefruit, lemon, mandarin, tangerine, and bergamot oils, so it was expected that various terpene hydroperoxides would be present in the treated mixtures being tested. Approximately 200 mg (1.0% w / v) of AKG-DiMeC12A salt was dissolved in 20 mL of mixed citrus oil, and POV measurements were taken as a function of time after addition. Untreated mixed citrus oil samples were handled and further tested in the same way as the treated oils, since sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0254] [Table 7]

[0255] These data represent an 89.0% reduction in POV within 72 hours (3 days) after addition of AKG-DiMeC12A. AKG-DiMeC12A may have been depleted by the 260-minute time point, as no further response occurred even after such extended periods.

[0256] Surface Tension Measurements of Aqueous AKG-DiMeC12A: To evaluate the surface-active properties of AKG-DiMeC12A, the resulting surface tension reduction in aqueous solutions was measured relative to pure water. Measurements were performed using the pendant drop method with a Kruss DSA100S tensiometer. A 0.14 wt% aqueous solution of AKG-DiMeC12A was used. This concentration was chosen to allow for comparison of the results with the literature value for 5 mM of the known surfactant sodium dodecyl sulfate (SDS), which is approximately 0.15 wt%. The results demonstrate that AKG-DiMeC12A possesses significant surface-active properties. Pure water - 71.57mN / m AKG-DiMeC12A - 32.08mN / m

[0257] For comparison, SDS at a concentration of 5 mM (approximately 0.15% by weight, very close to the 0.14% by weight used here) at 273 K has an air-water surface tension ranging from 33.5 to 35.5 mN / m, depending on the pH (see Hernainz, F. et al, Colloids Surf. A, 2002, 196, 19-24).

[0258] Example 9: Formation of a diammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and 2-(dimethylamino)ethanol (deanol, CAS No. 108-01-0) in a molar ratio of 1:2 1.461 g (0.01 mol) of α-ketoglutaric acid was dissolved in 10 mL of anhydrous acetone to obtain a clear solution. This solution was added to 1.783 g (0.02 mol) of neat 2-dimethylaminoethanol ("Dideanol") over 1-2 minutes with stirring. The opaque white emulsion was vortexed vigorously for 1 minute, during which time a second phase coalesced. This mixture was placed in the freezer overnight, during which the lower phase thickened to a very viscous, cloudy oil. While still cold, the upper layer was simply removed by decantation or pipette and discarded. Residual acetone was removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature. This resulted in a clear, colorless, viscous oil at room temperature containing the diammonium salt (AKG dideanol salt).

[0259] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 200 mg (1.0% w / v) of AKG dideanol salt was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, as sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0260] [Table 8]

[0261] Example 10: Formation of ammonium salts by reaction of pyruvic acid (CAS No. 328-50-7) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a 1:1 molar ratio 2.642 g (0.03 mol) of pyruvic acid was dissolved in 5 mL of anhydrous acetone to obtain a clear solution. This solution was added dropwise over 1-2 minutes with stirring to a second solution prepared from 3.575 g (0.03 mol) of NMDEA and 5 mL of anhydrous acetone. The resulting mixture became warm (approximately 35-45°C) and cloudy upon addition of the acid solution. The milky emulsion was vortexed vigorously for 1 minute, during which time the second phase coalesced. This mixture was placed in a freezer for at least 1 hour, during which the viscosity of the lower phase increased significantly but did not solidify. While still cold, the upper layer was simply removed by decantation or pipette and discarded. Residual acetone was removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature. This resulted in a clear, highly viscous, golden oil at room temperature containing the diammonium salt (PA-NMDEA salt).

[0262] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a blend of lime, orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 16.7% v / v (40 mL of oil in 200 mL of solvent, for a total of 240 mL of fragrance). Approximately 150 mg (1.0% w / v) of PA-NMDEA salt was dissolved in 15 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, as sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0263] [Table 9]

[0264] These data suggest that PA-NMDEA was depleted at 73.3 h because the POV of the samples did not decrease at all after that time, even with longer reaction times. This represents a reduction in POV of over 90%. Since the average untreated oil after 3 days was (6.66 + 6.58) / 2 = 6.62 mmol / L, 0.58 / 6.62 × 100 = 8.76% remaining, or a 91.2% reduction in POV.

[0265] Example 11: Formation of ammonium salt by reaction of phenylglyoxylic acid (PhGA, CAS No. 611-73-4) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a 1:1 molar ratio A clear solution was obtained by dissolving 1.501 g (0.01 mol) of PhGA in 5 mL of anhydrous acetone. This solution was added all at once to a second solution prepared from 1.192 g (0.01 mol) of NMDEA and 5 mL of anhydrous acetone. The resulting mixture became warm (approximately 30–35°C) and turned pale yellow, but no turbidity or precipitate formed. The solution was vortexed vigorously for 1 minute and placed in a freezer for 30 minutes. No precipitate or second layer formed, but the solution was clearly supersaturated. An attempt was made to remove the acetone solvent with a nitrogen stream, but a thick paste of white crystalline material formed almost instantly upon contact with the solution. As the mixture warmed to room temperature, the crystals began to redissolve in the acetone. Refreezing the product resulted in the reprecipitation of the highly crystalline product, and as much of the supernatant acetone as possible was removed by pipette while still cold. The remaining acetone was then removed under a nitrogen stream, yielding pure white needle-like crystals. The crystalline product containing the diammonium salt (PhGA-NMDEA salt) is highly hygroscopic and appears to liquefy very quickly upon exposure to ambient air. The needle-like white mass had to be kept under vacuum or a strict nitrogen blanket to maintain crystallinity. Due to hygroscopicity, no mass / yield data was available.

[0266] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a blend of lime, orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 16.7% v / v (40 mL of oil in 200 mL of solvent, for a total of 240 mL of fragrance). Approximately 150 mg (1.0% w / v) of PhGA-NMDEA salt was dissolved in 15 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, as sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0267] [Table 10]

[0268] These data suggest that the phenylglyoxylate moiety acts to reduce POV in the model fragrances, but is less reactive than the non-arylpyruvates tested. This difference in reactivity may be useful in some situations.

[0269] Example 12: Reduction of POV in sunflower oil according to one embodiment presented herein using 2-oxovaleric acid 25 mL of sunflower oil (from a pre-made, opened 1 quart container, approximately 25% atmospheric headspace, storage time unknown) was placed in a 30 mL vial at room temperature. 250 μL of 2-oxovaleric acid was added. The vial was shaken and allowed to sit on the benchtop at ambient temperature under laboratory lighting. No further processing was performed prior to POV testing.

[0270] POV measurements were made on sunflower oil before and after treatment with 2-oxovaleric acid. Because opening the bottles may fill the atmospheric headspace and increase the POV of the bottle contents, untreated oil was also periodically remeasured for comparison. Percent reductions were always calculated relative to the most recent POV value of untreated oil; when multiple measurements were made, the average value (shown in parentheses) was used for the calculation. The results are shown in the table below.

[0271] [Table 11]

[0272] The untreated sunflower oil experienced an almost 40% increase in POV (12.30 / 8.81 mmol / L x 100 = 139.6%) from simply standing in the bottle at room temperature for 15 days, with the headspace filled with ambient atmosphere during the short openings required to perform each sampling.

[0273] Conversely, treatment of sunflower oil with 0.83% v / v 2-oxovaleric acid reduced the POV after 15 days by 82.9% compared to untreated oil.

[0274] Example 13: Formation of ammonium salt by reaction of phenylpyruvic acid (CAS No. 156-06-9) and N,N-dimethyldecylamine (DiMeC10A, CAS No. 1120-24-7) in a 1:1 molar ratio 3.707 g (0.02 mol) of phenylpyruvic acid was dissolved in 10 mL of anhydrous acetone to give a clear solution. A separate solution was prepared from 3.283 g (0.02 mol) of N,N-dimethyldecylamine in 10 mL of anhydrous acetone. This amine solution was added dropwise to the phenylpyruvic acid solution with stirring over 2-3 minutes. No visible signs of reaction were observed, and no significant increase in temperature was observed. The mixture was briefly but vigorously shaken and then cooled in a freezer for 30 minutes. A thick network of white, cohesive, fine crystals formed, and a small amount of acetone was decanted from the solid mass while still cold and discarded. Most of the acetone solvent appeared to be trapped within the crystalline network, which was removed with a stream of nitrogen and then placed in a vacuum oven at room temperature. This gave a slightly off-white, fluffy crystalline solid in quantitative yield.

[0275] Reduction of POV in sunflower oil according to one embodiment presented herein using a diammonium salt formed by the reaction of phenylpyruvic acid and N,N-dimethyldecylamine (referred to herein as DiMeC10A-PhPA): 15 mL of sunflower oil, stored at room temperature in a plastic bottle for one year and unopened during this storage period, was placed in a 30 mL glass vial and 0.3032 g of DiMeC10A-PhPA was added. Most of the salt dissolved, but some undissolved solid remained. The mixture was left on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. The results are shown in the table below.

[0276] [Table 12]

[0277] The phenylpyruvate resulted in a very rapid reduction in the POV of sunflower oil.

[0278] Reduction of POV in a model fragrance according to one embodiment presented herein using a diammonium salt formed by the reaction of phenylpyruvic acid and N,N-dimethyldecylamine (referred to herein as DiMeC10A-PhPA): A model fragrance was prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of lime, orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 16.7% v / v (40 mL of oil in 200 mL of solvent, for a total of 240 mL of fragrance). Approximately 164 mg (1.1% w / v) of PhPA-DiMeC10A salt was dissolved in 15 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same manner as the treated fragrances, as handling of the sample (opening the bottle, stirring, etc.) can rapidly increase the POV. The results are shown in the table below.

[0279] [Table 13]

[0280] The above results represent an 87.2% reduction in POV after 7 days of addition of PhPA-DiMeC10A compared to untreated material.

[0281] Example 14: Formation of ammonium salt by reaction of α-oxo-2-furanacetic acid (CAS No. 1467-70-5) and N,N-dimethyldecylamine (DiMeC10A, CAS No. 1120-24-7) in a 1:1 molar ratio 2.114 g (0.015 mol) of α-oxo-2-furanacetic acid was dissolved in 10 mL of anhydrous acetone. The α-oxo-2-furanacetic acid was used as received from the supplier (a grayish-tan crystalline solid), resulting in a dark brown solution containing a small amount of undissolved, cohesive material. It was decided to use the "as is" material for preliminary screening, and if the screening results indicated so, it was possible to prepare purified starting material at a later time.

[0282] A separate solution was prepared from 2.780 g (0.015 mol) of N,N-dimethyldecylamine in 10 mL of anhydrous acetone. This amine solution was added dropwise over 5 minutes with stirring to the crude α-oxo-2-furanacetic acid solution. No visible signs of reaction were observed, and no significant increase in temperature occurred. The mixture was briefly shaken vigorously and then chilled in a freezer for 30 minutes. Since product precipitation still did not occur even at the low temperature, the acetone was removed with a stream of nitrogen and then placed in a vacuum oven at room temperature. This gave a quantitative yield of a brown, viscous oil, which crystallized to a tan solid after standing at freezer temperature for several days.

[0283] Reduction of POV in sunflower oil according to one embodiment presented herein using a diammonium salt (referred to herein as FAA-DiMeC10A) formed by the reaction of α-oxo-2-furanacetic acid and N,N-dimethyldecylamine: 15 mL of sunflower oil, stored at room temperature in a plastic bottle for one year and unopened during this storage period, was placed in a 30 mL glass vial and 0.3358 g of FAA-DiMeC10A was added. Most of the salt dissolved, but a small amount of dark brown, insoluble droplets remained. The mixture was left on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. The results are shown in the table below.

[0284] [Table 14]

[0285] Reduction of POV in a model fragrance according to one embodiment presented herein using a diammonium salt formed by the reaction of α-oxo-2-furanacetic acid and N,N-dimethyldecylamine (referred to herein as FAA-DiMeC10A): A model fragrance was prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of lime, orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 16.7% v / v (40 mL of oil in 200 mL of solvent, for a total of 240 mL of fragrance). Approximately 150 mg (1.0% w / v) of FAA-DiMeC10A salt was dissolved in 15 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same manner as the treated fragrances, as handling of the sample (opening the bottle, stirring, etc.) can rapidly increase the POV. The results are shown in the table below.

[0286] [Table 15]

[0287] The above results represent a 40.0% reduction in POV after 7 days of addition of FAA-DiMeC10A compared to untreated material. The α-oxo-2-furanacetic acid moiety appears to act to reduce POV in the model fragrances, but is less / slower reactive than the non-aryl α-oxocarboxylic acids tested.

[0288] Example 15: Formation of a diammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and tris[2-(2-(methoxyethoxy)ethyl]amine (CAS No. 70384-51-9) in a molar ratio of 1:2 2.922 g (0.02 mol) of α-ketoglutaric acid was dissolved in 10 mL of anhydrous acetone. A separate solution was prepared from 12.937 g (0.04 mol) of tris[2-(2-(methoxyethoxy)ethyl]amine (TMEEA)] in 5 mL of anhydrous acetone. This amine solution was added dropwise to the AKG solution with stirring over 2 minutes. No visible signs of reaction were observed, but the resulting mixture warmed slightly (approximately 35-45°C). The mixture was briefly but vigorously shaken and then cooled in a freezer for 30 minutes. Since no precipitation of the product still occurred even at the low temperature, the acetone was removed with a stream of nitrogen and then placed in a vacuum oven at room temperature. This gave a clear, golden-colored, slightly viscous oil in quantitative yield.

[0289] Reduction of POV in sunflower oil according to one embodiment provided herein using a diammonium salt (referred to herein as AKG-diTMEEA) formed by the reaction of α-ketoglutaric acid and tris[2-(2-(methoxyethoxy)ethyl]amine): 0.5081 g of AKG-diTMEEA was added to 15 mL of sunflower oil stored at room temperature in a plastic bottle that had not been opened during this storage period in a 30 mL glass vial. A larger than normal mass of this compound was used due to its very high molecular weight (792.96 g / mol). The salt completely dissolved to give a clear, golden oil. The solution was left on the benchtop in ambient laboratory light at room temperature and POV measurements were taken periodically. The results are shown in the table below.

[0290] [Table 16]

[0291] Example 16: Formation of a diammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and N,N-dimethyldodecylamine (CAS No. 112-18-5) in a molar ratio of 1:2 1.461 g (0.01 mol) of α-ketoglutaric acid was dissolved in 6 mL of anhydrous acetone. This solution was added dropwise over 1-2 min with stirring to a separate solution of 4.268 g (0.02 mol) of N,N-dimethyldodecylamine in 6 mL of anhydrous acetone. No visible signs of reaction were observed except that the combined solution warmed to approximately 35-40 °C. The mixture was briefly but vigorously shaken and then chilled in a freezer for 30 min. Although no precipitation of the product occurred even at the low temperature, when the mixture was shaken again, the entire amount solidified almost instantly to a solid white waxy material. The solid was warmed to 30-35 °C, allowing the trapped acetone to be removed with a nitrogen stream, and then placed in a vacuum oven at room temperature. This afforded a white waxy solid in quantitative yield.

[0292] Reduction of POV in sunflower oil according to one embodiment presented herein using a diammonium salt (referred to herein as AKG-DiMeC12A) formed by the reaction of α-ketoglutaric acid and N,N-dimethyldodecylamine: 15 mL of sunflower oil, stored at room temperature in a plastic bottle for one year and unopened during this storage period, was placed in a 30 mL glass vial and 0.3062 g of AKG-DiMeC12A was added. The salt did not completely dissolve, but a cloudy, gel-like suspension was obtained with the sunflower oil. The mixture was left on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. The results are shown in the table below.

[0293] [Table 17]

[0294] Example 17: Formation of ammonium salts by reaction of pyruvic acid (CAS No. 127-17-3) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a 1:1 molar ratio 2.642 g (0.03 mol) of pyruvic acid was dissolved in 5 mL of anhydrous acetone to obtain a clear solution. This solution was added dropwise with stirring over 1-2 minutes to a second solution prepared from 3.575 g (0.03 mol) of NMDEA and 5 mL of anhydrous acetone. The resulting mixture became warm (approximately 35-45°C) and cloudy upon addition of the acid solution. The milky emulsion was vortexed vigorously for 1 minute, during which time the second phase coalesced. This mixture was placed in a freezer for at least 1 hour, during which the viscosity of the lower phase increased significantly but did not solidify. While still cold, the upper layer was simply removed by decantation or pipette and discarded. Residual acetone was removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature. This resulted in a clear, golden-colored, highly viscous oil at room temperature in quantitative yield.

[0295] Reduction of POV in sunflower oil according to one embodiment presented herein using a diammonium salt (referred to herein as PA-NMDEA) formed by the reaction of pyruvic acid and N-methyldiethanolamine: 15 mL of sunflower oil stored at room temperature in a plastic bottle for one year, unopened during storage, was placed in a 30 mL glass vial and 0.2988 g of PA-NMDEA was added. While the salt appeared to be dissolved and / or dispersed, the resulting mixture was not completely transparent and had a translucent, colloidal appearance. The mixture was left to stand on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. The results are shown in the table below.

[0296] [Table 18]

[0297] Example 18: Reduction of POV in a model fragrance according to one embodiment presented herein using α-ketoglutaric acid α-Ketoglutaric acid is a strong acid, and a solution of 0.114 g of α-ketoglutaric acid in 10 mL of water had a measured pH of 1.75. Therefore, the amount of dissolved α-ketoglutaric acid in a hydroalcoholic fragrance base may have to be limited to prevent alteration of the sensory properties of the fragrance raw material.

[0298] A model fragrance was prepared using a 90 / 10 v / v ethanol / water solvent, to which a mixture of orange oil, grapefruit oil, and bergamot oil was added. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 240 mg (1.2% w / v) of α-ketoglutaric acid was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were performed the next day. The results are shown in the table below.

[0299] [Table 19]

[0300] These data show that the POV in the flavor formulation was completely reduced 24 hours after the flavor formulation was treated with α-ketoglutaric acid.

[0301] Example 19: Reduction of POV in a model fragrance according to one embodiment presented herein using oxaloacetic acid Oxaloacetate is known to be unstable in aqueous solutions (see H.A. Krebs, Biochemistry (1942) 36, 303-305), resulting in the evolution of carbon dioxide and pyruvate. Nevertheless, oxaloacetate is effective in reducing POV in solutions that solubilize it (e.g., hydroalcoholic flavorings). However, it is unclear whether the reduction in POV occurs directly through oxaloacetate, through free pyruvate, or both. Analysis of the reaction products (acetic acid vs. malonic acid) could distinguish between the two pathways, but this was not pursued here.

[0302] A model fragrance was prepared using a 90 / 10 v / v ethanol / water solvent, to which a mixture of orange oil, grapefruit oil, and bergamot oil was added. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 166 mg (0.83% w / v) of oxaloacetic acid was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were taken at the times indicated in the table below.

[0303] [Table 20]

[0304] These data show that the POV in the fragrance blend was completely reduced 24 hours after treatment of the fragrance blend with oxaloacetic acid.

[0305] Example 20: Formation of ammonium salt by reaction of phenylglyoxylic acid (CAS No. 611-73-4) and 1-(2-hydroxyethyl)-2-imidazolidinone (HEI, CAS No. 3699-54-5) in a 1:1 molar ratio 3.003 g (0.02 mol) of phenylglyoxylic acid was dissolved in 10 mL of anhydrous acetone to give a clear solution. A separate solution was prepared from 2.603 g (0.02 mol) of 1-(2-hydroxyethyl)-2-imidazolidinone in 10 mL of anhydrous acetone. Because 1-(2-hydroxyethyl)-2-imidazolidinone was supplied as a 75% w / w aqueous solution, the actual amount of this 75% reagent used to compensate for the mass of the solvent water was 3.471 g. The 1-(2-hydroxyethyl)-2-imidazolidinone amine solution was added dropwise to the phenylglyoxylic acid solution with stirring over a period of 3 minutes. No visible signs of reaction were observed, and there was no significant increase in temperature. The mixture was briefly but vigorously shaken and then cooled in a freezer for 30 minutes. Since the product still did not precipitate even at the low temperature, the acetone solvent was removed with a stream of nitrogen and then placed in a vacuum oven at room temperature. This gave a clear, pale yellow, highly viscous oil in quantitative yield.

[0306] Reduction of POV in a model fragrance according to one embodiment presented herein using an ammonium salt formed by the reaction of phenylglyoxylic acid and 1-(2-hydroxyethyl)-2-imidazolidinone (referred to herein as PhGA-HEI): A model fragrance was prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of lime, orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were added to the solvent at approximately 16.7% v / v (40 mL oil in 200 mL solvent, totaling 240 mL fragrance). Approximately 150 mg (1.0% w / v) of PhGA-HEI salt was dissolved in 15 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same manner as the treated fragrances, as handling of the sample (opening the bottle, stirring, etc.) can rapidly increase the POV. The results are shown in the table below.

[0307] [Table 21]

[0308] The above results represent a 58.8% reduction in POV after 7 days of addition of PhGA-HEI compared to untreated material. The phenylglyoxylic acid moiety acts to reduce POV in the model fragrances, but is believed to be less / slower reactive than the non-aryl α-oxocarboxylic acids tested. This difference in reactivity may be useful in some situations.

[0309] Example 21: Formation of a diammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and 1-(2-hydroxyethyl)-2-imidazolidinone (HEI, CAS No. 3699-54-5) in a molar ratio of 1:2 2.922 g (0.02 mol) of α-ketoglutaric acid (AKG) was dissolved in 10 mL of anhydrous acetone to give a clear solution. A separate solution was prepared from 5.206 g (0.04 mol) of 1-(2-hydroxyethyl)-2-imidazolidinone (HEI) in 10 mL of anhydrous acetone. HEI was supplied as a 75% w / w aqueous solution, so the actual amount of this 75% reagent used to compensate for the mass of the solvent water was 6.942 g. This HEI amine solution was added dropwise to the AKG solution with stirring over a period of 3 minutes. No visible signs of reaction were observed, and there was no significant increase in temperature. The mixture was briefly but vigorously shaken and then cooled in a freezer for 1 hour. Since no precipitation of the product occurred even at low temperatures, the acetone solvent was removed with a stream of nitrogen and then placed in a vacuum oven at room temperature. This afforded a clear, colorless, highly viscous oil in quantitative yield.

[0310] Reduction of POV in a model fragrance according to one embodiment presented herein using a diammonium salt formed by the reaction of α-ketoglutaric acid and 1-(2-hydroxyethyl)-2-imidazolidinone (referred to herein as AKG-HEI): A model fragrance was prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of lime, orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 16.7% v / v (40 mL of oil in 200 mL of solvent, for a total of 240 mL of fragrance). Approximately 150 mg (1.0% w / v) of AKG-HEI salt was dissolved in 15 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same manner as the treated fragrances, as handling of the sample (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0311] [Table 22]

[0312] The above results represent a 92.1% reduction in POV after 7 days of addition of AKG-DiHEI compared to untreated material.

[0313] Example 22: Formation of an ammonium salt by reaction of α-ketoglutaric acid (CAS No. 328-50-7) and N,N-dimethyldodecylamine (DiMeC12A, CAS No. 112-18-5) in a 1:1 molar ratio (referred to herein as AKG-mono(DiMeC12A)) 2.922 g (0.02 mol) of α-ketoglutaric acid was dissolved in 12 mL of anhydrous acetone. This solution was added dropwise to a separate solution of 4.268 g (0.02 mol) of N,N-dimethyldodecylamine in 6 mL of anhydrous acetone with stirring over a period of 1-2 minutes. The mixture was shaken, but no visible signs of reaction were observed, except that the combined solution warmed to approximately 35-40°C. The mixture remained clear for several minutes, but upon reshaking, the entire mixture almost instantly solidified to a solid white crystalline block. The solid was warmed to 30-35°C, allowing the trapped acetone to be removed with a stream of nitrogen, and then placed in a vacuum oven at room temperature. This afforded a white waxy solid in quantitative yield.

[0314] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 200 mg (1.0% w / v) of AKG-monoMeCl2A salt was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, as sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0315] [Table 23]

[0316] These data demonstrate a global and complete reduction in POV within 26 hours after addition of AKG-mono(DiMeC12A).

[0317] In addition to the treatments performed on the model fragrances described above, similar experiments were performed on mixed citrus oils. The mixed citrus oil samples were prepared by combining lime, orange, grapefruit, lemon, mandarin, tangerine, and bergamot oils, so it was expected that various terpene hydroperoxides would be present in the treated mixtures being tested. Approximately 200 mg (1.0% w / v) of AKG-mono(DiMeC12A) salt was added to 20 mL of mixed citrus oil, but most of it did not dissolve. POV measurements were taken as a function of time after addition. Untreated mixed citrus oil samples were handled and further tested in the same way as the treated oils, since sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0318] [Table 24]

[0319] These data represent a 94.2% reduction in POV compared to untreated material 28.0 hours after addition of AKG-mono(DiMeC12A) salt.

[0320] Surface Tension Measurements of Aqueous AKG-mono(DiMeC12A): To evaluate the surface-active properties of AKG-mono(DiMeC12A), the resulting decrease in surface tension in aqueous solutions was measured relative to pure water. Measurements were performed using the pendant drop method on a Kruss DSA100S tensiometer. A 0.14 wt% aqueous solution of AKG-mono(DiMeC12A) was used for the measurements. This concentration was chosen to allow for comparison of the results with the literature value for 5 mM of the known surfactant sodium dodecyl sulfate (SDS), which is approximately 0.15 wt%. The results demonstrate that AKG-mono(DiMeC12A) possesses significant surface-active properties. Pure water - 71.57mN / m AKG-Mono DiMeC12A - 32.93mN / m

[0321] For comparison, SDS at a concentration of 5 mM (approximately 0.15% by weight, very close to the 0.14% by weight used here) at 273 K has an air-water surface tension ranging from 33.5 to 35.5 mN / m, depending on the pH (see Hernainz, F. et al, Colloids Surf. A, 2002, 196, 19-24).

[0322] Example 23: Formation of ammonium salt by reaction of indole-3-pyruvic acid (I-3-PA, CAS No. 392-12-1) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a 1:1 molar ratio 0.61 g (0.003 mol) of I-3-PA-NMDEA was placed in 4 mL of methanol, but it only partially dissolved. A separate mixture was prepared from 0.357 g (0.003 mol) of NMDEA in 2 mL of acetone, which formed a clear solution. This amine solution was added all at once to the indole-3-pyruvic acid and vortexed vigorously for 1 minute. Because some solids remained undissolved, the mixture was placed in a 40 °C water bath. Upon heating, all material dissolved, forming a clear, deep orange solution. The mixture was cooled to room temperature, but no precipitate formed. The solution was placed in a freezer for 30 minutes, during which time pale pink needle-like crystals precipitated. The mother liquor was removed with a pipette, but was found to contain a significant amount of impure material, which could be further recovered by blowing off the solvent under a stream of nitrogen, yielding a deep orange solid. For preliminary purposes, the two portions of the product were recombined until a more efficient crystallization procedure was developed. The yield was quantitative.

[0323] Model fragrances were prepared using 90 / 10 v / v ethanol / water as the solvent and a mixture of orange, grapefruit, and bergamot oils as the perfume oils. The mixed citrus oils were loaded into the solvent at approximately 19.4% v / v (6 mL of oil in 25 mL of solvent). Approximately 244 mg (1.2% w / v) of I-3-PA-NMDEA salt was dissolved in 20 mL of the mixed citrus fragrance, and POV measurements were taken as a function of time after addition. Untreated fragrance samples were handled and further tested in the same way as the treated fragrances, since sample handling (opening the bottle, stirring, etc.) can rapidly increase POV. The results are shown in the table below.

[0324] [Table 25]

[0325] These data demonstrate a rapid reduction in POV compared to untreated material 60 minutes after addition of I-3-PA-NMDEA salt.

[0326] Example 24: Reduction of POV in a model fragrance according to one embodiment presented herein using a diammonium salt made from α-ketoglutaric acid (CAS No. 328-50-7) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a molar ratio of 1:2 incorporated onto a solid support It was observed that reduction of POV in citrus oils can occur even with α-oxocarboxylate salts that are substantially insoluble in the citrus oil being treated. This observation appeared to apply to both solid and liquid salts (which tend to be highly viscous), although the rate and efficiency of reduction was not as high as with soluble salts. It was hypothesized that the surface area of ​​contact between the α-oxocarboxylate salt phase and the citrus oil phase was likely the limiting factor; if so, methods to increase the contact area should promote a more rapid and facile reaction.

[0327] To this end, we attempted to spread a thin, highly disperse layer of a diammonium salt formed from α-ketoglutaric acid and two equivalents of N-methyldiethanolamine (AKG-DiNMDEA) onto a chemically inert, high-surface-area solid support. In this example, we used a very thin, stainless steel, commercially available, household scrubbing pad (3M Scotch-Brite Scrubby® pad).

[0328] Preparation of AKG-DiNMDEA-Coated Pads: A single pad was washed as follows: the pad was placed in a 250 mL glass beaker and completely covered with pentane. The beaker was sonicated for 3 minutes, the pentane was drained, and the procedure was repeated using acetone. The acetone was also drained, and the pad was dried in a vacuum oven at room temperature for 1 hour. The pad weighed 19.229 g both before and after the washing procedure, so no appreciable mass loss was observed as a result of washing.

[0329] A solution was prepared from 3.0 g of AKG-DiNMDEA and 10 mL of fragrance-grade ethanol. The solution was spread onto a stainless steel pad with a pipette and loaded onto the pad by drying the ethanol under vacuum at room temperature. This was best done by dividing the solution into approximately three portions with a drying step between each. The pad was not able to completely hold so much solution, resulting in some spillage on each attempt. Once all the ethanol was removed, the viscous AKG-DiNMDEA appeared to adhere firmly to the pad, allowing the pad to be moved between containers without losing its liquid coating.

[0330] Blended Citrus Oil Processing: A blended citrus oil sample was produced by combining lime, orange, grapefruit, and bergamot oils, so it was expected that various terpene hydroperoxides would be present in the processed blend to be tested. Two separate 250 mL glass bottles were filled with 150 mL of blended citrus oil each. This allowed for a significant atmospheric headspace within the sealed bottle, with fresh atmosphere / oxygen being replenished each time the bottle was opened to remove an aliquot for testing. This configuration was designed to mimic the oxygen exposure experienced during normal handling in the production of drums of citrus oil stock and should result in realistic levels of autoxidation of the oils contained therein.

[0331] The AKG-DiNMDEA-coated pad was placed in one of the bottles (treated sample) and completely submerged beneath the mixed citrus oil. The second bottle contained nothing but the mixed citrus oil (untreated sample). These bottles were left stationary on the lab bench under ambient temperature and lighting conditions throughout the test period. Periodically, aliquots were removed from each bottle for POV testing. It took several weeks for significant downward flow of the coating from the pad to occur, as evidenced by the appearance of a pool of AKG-DiNMDEA collecting at the bottom of the container. The interphase contact area likely decreased as this flow progressed, potentially reducing the efficiency of the reduction reaction. Nevertheless, significant protection of the treated citrus oil from autoxidation-induced POV increases occurred, as reported in the table below and Figures 5 and 6.

[0332] Reloading the Pad: After 26 days, it was observed that the POV of the treated samples began to increase slightly (see Figure 5). At the same time, the % POV reduction of the treated samples compared to the untreated samples began to decrease slightly (see Figure 6). This was interpreted as meaning that the coated pads were no longer functioning effectively, likely due to chemical consumption of the AKG-DiNMDEA. Alternatively, the viscous liquid AKG-DiNMDEA may have been slowly flowing downward from the stainless steel coil of the pad. This created a small surface area pool, resulting in reagent waste due to insufficient contact with the citrus oil.

[0333] The pad was removed from the mixed citrus oil and washed successively with 100 mL each of acetone, then 95% ethanol, and then acetone again. The washed pad was vacuum dried at room temperature and reloaded with AKG-DiNMDEA. This time, a simpler procedure for reloading / reactivating / reloading the Scrubby® was attempted. Instead of dispensing a solution and allowing the solvent to evaporate, the viscous AKG-DiNMDEA oil was simply rubbed into the steel coil. Approximately 3.2 g of AKG-DiNMDEA was placed on the surface of the steel pad and kneaded with gloved hands to distribute the oil as evenly as possible. The reloaded Scrubby® was then returned to the container of treated citrus oil, and POV monitoring continued as before. The time points corresponding to reloading are indicated by vertical purple lines in Figures 5 and 6.

[0334] [Table 26-1]

[0335] [Table 26-2]

[0336] Example 25: Reducing POV in Consumer Goods Selection According to an Embodiment Presented herein This example reports the treatment of exemplary consumer goods formulations. The consumer goods formulations had measurable oxidation levels as-is, as shown in the table below, but the POV levels were low, except for the all-purpose cleaner. None of the samples were perfumed, so the POV was related to the autoxidized base ingredient. Five consumer goods formulations were spiked with heavily oxidized limonene produced in a photoreactor as a source of mixed limonene hydroperoxide isomers (POV was 1434 mmol / L). The oxidized limonene was added at a level of 10 μL per gram, respectively, resulting in an additional POV of approximately 14.3 mmol / L to the existing neat POV.

[0337] In both cases, treatment with α-oxocarboxylic acid ammonium salts resulted in a rapid and extensive reduction in the POV of the samples. The hydroperoxides present in the samples were consumed / destroyed through a controlled, targeted reaction with the α-oxocarboxylic acid, producing harmless, predictable by-products. In some cases, the reduction in POV was much slower but more consistent in untreated samples. This is likely due to limonene hydroperoxide reacting with and oxidizing the base ingredients to form unknown by-products. This can often have detrimental effects on the formulation, such as the formation of offensive odors, discoloration, and changes in physical properties. While this uncontrolled and unplanned reduction in POV may reduce the skin sensitization potential of the samples through consumption of sensitizing hydroperoxides, it is not necessarily positive for the formulation in all aspects.

[0338] [Table 27]

[0339] Sample preparation: 0.4 mL of limonene oxide was added to 40 mL (sample #3) or 40 g (samples #1, 2, 4, and 5) of each sample and mixed until homogeneous. Half of each spiked consumer product sample was transferred to a second container, treated with 0.5–1% (w / w) 2-oxocarboxylic acid ammonium salt as described in the table below, and mixed until homogeneous. Each of the five pairs of treated and untreated samples was placed on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. The results are described below.

[0340] [Table 28]

[0341] [Table 29]

[0342] [Table 30]

[0343] [Table 31]

[0344] [Table 32]

[0345] [Table 33]

[0346] Example 26: Reducing POV in a selection of essential oils obtained from non-citrus sources according to one embodiment presented herein In this example, a series of non-citrus essential oils were treated with AKG-DiTMEEA (α-ketoglutaric acid (AKG, CAS No. 328-50-7) and tris[2-(2-(methoxyethoxy)ethyl]amine (TMEEA, CAS No. 70384-51-9) in a 1:2 molar ratio), as described below. The results indicate that the proposed treatment is effective for a wide range of essential oils, including a wide range of terpenes and other small organic molecules, such as aromatic compounds. Thus, it appears that a very wide range of organic hydroperoxides are present as autoxidation products in these other oil species, and all of them are reduced by 2-oxoacids (specifically, α-ketoglutarate ammonium salt, in this case).

[0347] The data below show nine oils, along with the POV obtained for each as is from the manufacturing stock. For each oil, 20 mL was placed in separate 30 mL glass vials, and the following procedure was followed daily for 8 days: the vials were opened to refresh the atmospheric headspace, reclosed and shaken to maximize air-liquid contact, and then stored on the benchtop under ambient laboratory temperature and lighting conditions. This procedure was designed to mimic typical handling of containers in a manufacturing environment, where oil is consumed in many small aliquots rather than the entire container at once.

[0348] On the fourth day, each oil sample was split in half and two 10 mL aliquots were placed in separate vials to generate "treated" and "untreated" samples. To the treated samples of each oil type, AKG-DiTMEEA was added according to the dosage chart below. Because the POV of pine oil was significantly higher, the dosage and measurement protocol was slightly different from the other oils. The daily opening, shaking, and settling procedure continued for four more days before POV measurements were taken. It can be seen that handling the untreated oil in this manner for eight days resulted in a significant increase in the POV measurements.

[0349] Siberian pine oil had an unusually high POV, to the point where stoichiometric depletion of AKG-DiTMEEA was likely. Therefore, two levels of AKG-DiTMEEA treatment were tested: x2 and x4, which are the treatments used with other oils. This suggests that AKG-DiTMEEA has a high molecular weight due to its large amine group, resulting in a low stoichiometric capacity to scavenge hydroperoxides per unit mass, and therefore may require a larger amount to fully restore this pine oil sample. A different 2-oxoacid salt with a lower molecular weight may be a better option.

[0350] [Table 34]

[0351] [Table 35]

[0352] [Table 36]

[0353] Example 27: Preparation and Testing of High Viscosity 2-Oxoacid-Containing Materials; AKG-Amine Disalt-Containing Materials Made Using Polydentate Amines and / or Polydentate Carboxylic Acids In this example, the following amines were used to prepare salts of α-ketoglutaric acid: [Table 37]

[0354] Seven substituted ammonium salts of α-ketoglutaric acid ("AKG") were prepared using the following general procedure. AKG (approximately 0.01 mole, approximately 1.461 g) was dissolved in 10 mL of anhydrous acetone to obtain a clear solution. This solution was added all at once to a solution of the mixed amines in 5 mL of acetone. A total of 0.02 moles of basic N atoms were provided by each amine mixture. This completely neutralized the two carboxylic acid moieties present in 0.01 mole of AKG. The resulting opaque white emulsion was vortexed vigorously for 2-3 minutes, during which time a second phase coalesced and separated from the milky white mixture. This mixture was placed in a freezer overnight, during which the lower phase thickened to a waxy solid. While still cold, the upper layer was removed by decantation and discarded. Residual acetone was removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature for at least 2 hours. In both cases, this produced a colorless or yellow oil with high viscosity at room temperature. This procedure was repeated to prepare seven different AKG cross-linked disalts as shown below: [Table 38]

[0355] A blend of citrus oils was prepared for use in the AKG salt test as follows: Approximately equal amounts of cold-pressed orange, lemon, lime, bergamot, and grapefruit oils were combined to form a blend. These citrus oils had been extensively handled for other purposes in the laboratory for several months and had undergone various degrees of autoxidation, but each had significant POV values. The combined oils used at the beginning of the experiment had a POV of approximately 18 mmol / L, but handling during the experimental procedure increased the POV of the untreated oil. The treated oils also underwent the same handling (the vials were opened between sampling times, and the headspace was refreshed from ambient atmosphere). The percentage POV reduction at each time point was calculated relative to the POV of the untreated oil at that time point, rather than the initial POV value.

[0356] Sample preparation for testing / treatment: A series of vials, each filled with approximately 0.2 g of one of the seven AKG ionically cross-linked disalts (#1–#7, prepared above), was added to 5 mL of mixed citrus oil. Each mixture was vortexed for 1–2 minutes and then allowed to settle on the benchtop under ambient laboratory light and temperature conditions. This process was repeated for each salt, preparing a total of seven samples. POV measurements were taken as a function of time after addition. Untreated citrus oil (also 5 mL) was handled similarly to the treated oil and further tested, as sample handling can rapidly increase POV. Preparations #1–#7 were virtually insoluble and all formed second phases in the mixed citrus oil.

[0357] POV measurements were taken periodically over a 3-4 day period on seven treated and one untreated citrus oil sample. The results are shown below and in Figures 21-34: #1. AKG-NMDEA (90%) + THED (10%) [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7), N-methyldiethanolamine (90%, NMDEA, CAS No. 105-59-9), and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (10%, THED, CAS No. 140 07 8) in a molar ratio of 1:1.8:0.1] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 4-day period. The results are shown in the table below and in Figures 21 and 22.

[0358] [ka]

[0359] [Table 39]

[0360] #2. AKG-NMDEA (80%) + THED (20%) [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (80%, NMDEA, CAS No. 105-59-9) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140 07-8) in a molar ratio of 1:1.6:0.2] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 4-day period. The results are shown in the table below and in Figures 23 and 24.

[0361] [ka]

[0362] [Table 40]

[0363] #3. AKG-NMDEA (80%) + THED (10%) + BDMPP (10%) [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (80%, NMDEA, CAS No. 105-59-9), N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (10%, THED, CAS No. 140-07-8), and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (10%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:1.6:0.1:0.067] was used to reduce the POV of a blend of citrus oils. POV measurements were performed over a 4-day period. The results are shown in the table below and in Figures 25 and 26.

[0364] [ka]

[0365] [Table 41]

[0366] #4. AKG-NMDEA (60%) + THED (20%) + BDMPP (20%) [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (60%, NMDEA, CAS No. 105-59-9), N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140-07-8), and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:1.2:0.2:0.134] was used to reduce the POV of a blend of citrus oils. POV measurements were performed over a 3-day period. The results are shown in the table below and in Figures 27 and 28.

[0367] [ka]

[0368] [Table 42]

[0369] #5. AKG-THED [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (20%, THED, CAS No. 140 07-8) in a 1:1 molar ratio] was used to reduce the POV of blended citrus oils. POV measurements were performed over a 3-day period. The results are shown in the table below and in Figures 29 and 30.

[0370] [ka]

[0371] [Table 43]

[0372] #6. AKG-THED (80%) + BDMPP (20%) [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7) in a molar ratio of 1:0.8:0.13] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 4-day period. The results are shown in the table below and in Figures 31 and 32.

[0373] [ka]

[0374] [Table 44]

[0375] #7. AKG-BDMPP [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328 50-7) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151 63-7) in a molar ratio of 1:0.67] was used to reduce the POV of mixed citrus oils. POV measurements were performed over a 4-day period. The results are shown in the table below and in Figures 33 and 34.

[0376] [ka]

[0377] [Table 45]

[0378] Example 28: Treatment of mixed citrus model flavor with AKG-ammonium citrate Citric acid is a tridentate carboxylic acid that can form three ionic bonds with amine compounds.Without intending to be limited to a particular theory, it is expected that citric acid can cause branching in the ionic bond network formed in these preparations, and branching can increase viscosity.The preparations were tested in mixed citrus oil raw materials and hydroalcoholic model perfumes made from mixed citrus oils.The prepared AKG salts were insoluble in pure citrus oil raw materials, but still acted as follows.They were completely dissolved in hydroalcoholic model perfumes, and when dissolved, they acted more quickly.

[0379] Preparation of citrus model fragrance: 180 mL of flavor-grade ethanol, 20 mL of distilled water, and 40 mL of mixed citrus oil were combined and vortexed. The resulting oil loading was 40 mL oil / 240 mL total = 16.67% v / v, resulting in a slightly cloudy yellow solution.

[0380] The list of amines and acids used in the preparation of AKG salt preparations was as follows: [Table 46]

[0381] Four citric acid-containing, ionically bridged substituted ammonium salts of AKG were prepared using the following general procedure. AKG (approximately 0.009 mol, approximately 1.314 g) and citric acid (0.001 mol × 2 / 3 = 0.000667 mol, 0.128 g) were dissolved in 10 mL of anhydrous acetone by vigorously vortexing. This solution was added all at once to a solution of the mixed amines in 5 mL of acetone. A total of 0.02 mol of basic N atoms was provided by each amine mixture. This completely neutralized the carboxylic acid moieties present in 0.009 mol of AKG and 0.000667 mol of citric acid (CA). The resulting opaque white emulsion was vigorously vortexed for 2–3 minutes, during which time a second phase coalesced and separated from the milky white mixture. This mixture was placed in the freezer overnight, during which the lower phase thickened to a waxy solid. While still cold, the upper layer was removed by decantation and discarded. Residual acetone was removed from the lower product layer with a stream of nitrogen, followed by treatment in a vacuum oven at room temperature for at least 4 hours. In each case, this produced a colorless or yellow oil of high viscosity at room temperature. This procedure was repeated to produce four different AKG / CA crosslinked disalts, as shown in the table below: [Table 47]

[0382] Sample Preparation for Testing / Treatment: Model citrus flavor (15 mL each, in four separate 16 mL vials) was treated with one of four AKG-CA salts (approximately 0.2 g each, see table below). All AKG-CA salts dissolved in the model citrus flavor, resulting in a yellow solution with little haze and no color change, appearing indistinguishable from the untreated sample. These solutions, treated and untreated, were left undisturbed on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. No color change occurred for all treated samples throughout the duration of the experiment. Results are shown in the table below and in Figures 35-42.

[0383] [Table 48]

[0384] A. AKG-CA+NMDEA [a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9) in a molar ratio of 9:0.67:20] was used to reduce the POV of a mixed citrus model fragrance. POV measurements were carried out over a 5-day period. The results are shown in the table below and in Figures 35 and 36.

[0385] [ka]

[0386] [Table 49]

[0387] B. AKG-CA+THED [a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (THED, CAS No. 140-07-8) in a molar ratio of 9:0.67:10] was used to reduce the POV of a mixed citrus model fragrance. POV measurements were performed over a 5-day period. The results are shown in the table below and in Figures 37 and 38.

[0388] [ka]

[0389] [Table 50]

[0390] C. AKG-CA-THED (80%) + BDMPP (20%): [a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) in a molar ratio of 9:0.67:8:1.3, and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7)] was used to reduce the POV of a mixed citrus model fragrance. POV measurements were performed over a 5-day period. The results are shown in the table below and in Figures 39 and 40.

[0391] [ka]

[0392] [Table 51]

[0393] D. AKG-CA + BDMPP [a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:6.7] was used to reduce the POV of a mixed citrus model fragrance. POV measurements were carried out over a 4-day period. The results are shown in the table below and in Figures 41 and 42.

[0394] [ka]

[0395] [Table 52]

[0396] Example 29: Treatment of mixed citrus oils with AKG-ammonium citrate The compounds used were prepared as described above in Examples 27 and 28. The major difference between these two experiments is that both AKG-citrate salts were soluble in the hydroalcoholic model fragrances but insoluble in the mixed citrus oil itself.

[0397] Mixed citrus oil treatment: 5 mL of mixed citrus oil was added to each of two vials filled with approximately 0.2 g of AKG disalt (C: AKG (90%) - CA (10%) - THED (80%) + BDMPP (20%), or D: AKG (90%) - CA (10%) + BDMPP). The vials were vortexed for 2 minutes and then placed on the benchtop under ambient laboratory light and temperature conditions. Periodic POV measurements were taken as a function of time after addition. The results are shown in the table below and in Figures 43-46.

[0398] C: AKG (90%) - CA (10%) + THED (80%) - BDMPP (20%): [α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) in a molar ratio of 9:0.67:8:1.3 and a crosslinked diammonium salt made from N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (80%, THED, CAS No. 140-07-8) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (20%, BDMPP, CAS No. 67151-63-7)] were used to reduce the POV of blended citrus oils. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 43 and 44.

[0399] [ka]

[0400] [Table 53]

[0401] D. AKG (90%)-CA (10%) + BDMPP [a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and citric acid (10%, CA, CAS No. 77-92-9) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9:0.67:6.7] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 45 and 46.

[0402] [ka]

[0403] [Table 54]

[0404] Example 30: 2-Oxo Acid Salt-Containing Materials Prepared Using Polydentate / Polymeric Acids and / or Polydentate / Polymeric Amine / Bases Without intending to be limited to any particular theory, the concept of forming a network of ionic crosslinks that increases the viscosity of 2-oxoacid salt-containing materials or creates gel-type rheological behavior in the 2-oxoacid salt phase can be extended beyond bidentate or tridentate acids or bases. For example, when polymeric acids such as polyacrylic acid or polymeric amines such as chitosan are used as components, the ionic network formed can be complex and extensive. Such extensive networks can cause the material to exhibit very viscous, gel-like, or even solid / granular bulk physical properties. As shown below, the materials so produced did indeed exhibit these physical properties, yet retained the ability to react with terpene hydroperoxides contained in a distinct, separate phase composed of mixed citrus oils.

[0405] [Table 55]

[0406] [Table 56]

[0407] Salt preparation procedure: Four vials were separately filled with AKG (0.0099 or 0.0095 mol, 1.446 or 1.388 g) and polyacrylic acid (0.0002 or 0.001 mol, 0.0144 or 0.072 g) according to the table above. Anhydrous acetone was added to each vial (10 mL for #1 and #3, 14–15 mL for #2 and #4; additional acetone was required to dissolve the PAA). Each vial was vortexed for 30 seconds. Because a small amount of white solid, likely an impurity from AKG, did not completely dissolve and settled to the bottom of the vial, the upper clear solution was added all at once to 5 mL of amine in acetone (0.02 mol total N groups, 2.363 g THED or 1.636 g BDMPP, see table above). The opaque white emulsion was vortexed vigorously for 2 minutes, during which time the second phase coalesced. The mixture was placed in the freezer over the weekend, during which time the bottom layer thickened to a waxy solid. While still cold, the top layer was decanted and discarded. Residual acetone was removed from the bottom product layer with a nitrogen stream, followed by storage in a vacuum oven at room temperature for 7 days.

[0408] #1P and #4P were used in the POV reduction test in mixed citrus oils as shown below.

[0409] Mixed citrus oil treatment: 5 mL of mixed citrus oil was added to a vial filled with approximately 0.2 g of the AKG-PAA salt preparation (as listed above). The mixture was vortexed for 2 minutes and then allowed to rest on the benchtop under ambient laboratory light and temperature conditions. Periodically, POV measurements were taken as a function of time after addition. None of the AKG-PAA salt preparations dissolved in the oil. The results are shown in the table below and in Figures 47-50.

[0410] #1P: AKG (99%) - PAA1 (%) + THED: [a cross-linked diammonium salt made from α-ketoglutaric acid (99%, AKG, CAS No. 328-50-7) and polyacrylic acid (1%, PAA, CAS No. 9003-01-4) and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (THED, CAS No. 140-07-8) in a molar ratio of 9.9:0.2:10] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 47 and 48.

[0411] [ka]

[0412] [Table 57]

[0413] #4P: AKG (95%)-PAA (5%) + BDMPP [a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) in a molar ratio of 9.5:1:6.7] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 49 and 50.

[0414] [ka]

[0415] [Table 58]

[0416] Example 31: AKG Amine Salt Prepared with Both Polyacrylic Acid and Polyamine Components [Table 59]

[0417] General procedure for preparing AKG-PAA-PEI ammonium salt: Four vials were separately filled with AKG (0.0095 or 0.01 mol, 1.388 g or 1.484 g) and poly(acrylic acid) (0.001 mol, 0.072 g) according to the table above (the actual masses used are shown in the table), and 14 mL of anhydrous acetone was added to each. Each vial was vortexed for 30 s. Because a small amount of white solid, likely an impurity from AKG, did not completely dissolve and settled to the bottom of the vial, the upper, clear solution was added all at once to 10 mL of the amine mixture (0.02 mol total N-groups, see the table above) dissolved in acetone. The opaque white emulsion was vortexed vigorously for 2 minutes, during which time a second phase coalesced. This mixture was placed in the freezer over the weekend, during which the lower phase thickened to a waxy solid. While still cold, the upper layer was decanted and discarded. Residual acetone was removed from the bottom product layer with a stream of nitrogen, followed by treatment in a vacuum oven at room temperature for 7 days.

[0418] [Table 60]

[0419] Mixed citrus oil treatment: To a vial filled with approximately 0.2 g of the AKG-PAA-PEI salt preparation (as listed above), 5 mL of mixed citrus oil was added. The mixture was vortexed for 2 minutes and then allowed to rest on the benchtop under ambient laboratory light and temperature conditions. Periodic POV measurements were taken. The results are shown in the table below and in Figures 51-58.

[0420] APP1: AKG (95%)-PAA (5%) + THED (95%)-PEI (5%): [a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) in a molar ratio of 9.5:1:9.5:1 and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (95%, THED, CAS No. 140 07-8) and polyethyleneimine (5%, PEI, CAS No. 9002-98-6)] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 51 and 52.

[0421] [ka]

[0422] [Table 61]

[0423] APP2: AKG (95%)-PAA (5%) + BDMPP (95%)-PEI (5%): [α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) in a molar ratio of 9.5:1:6.3:1 and a cross-linked diammonium salt made from 1-[bis[3-(dimethylamino)propyl]amino]-2-propanol (BDMPP, CAS No. 67151-63-7) and polyethyleneimine (5%, PEI, CAS No. 9002-98-6)] were used to reduce the POV of mixed citrus oils. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 53 and 54.

[0424] [ka]

[0425] [Table 62]

[0426] APP3: AKG (95%) - PAA (5%) + PEI: [a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyacrylic acid (5%, PAA, CAS No. 9003-01-4) and polyethyleneimine (PEI, CAS No. 9002-98-6) in a molar ratio of 9.5:1:20] was used to reduce the POV of blended citrus oils. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 55 and 56.

[0427] [ka]

[0428] [Table 63]

[0429] APP4:AKG+PEI: [a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and polyethyleneimine (PEI, CAS No. 9002-98-6) in a 1:2 molar ratio] was used to reduce the POV of blended citrus oils. POV measurements were performed over a 12-day period. The results are shown in the table below and in Figures 57 and 58.

[0430] [ka]

[0431] [Table 64]

[0432] Example 32: Materials containing polydentate acids and amines with increased hydrophobicity to produce more hydrophobic 2-oxoacid salt phases Due to the highly ionic nature of the 2-oxo acid ammonium salt phases prepared from α-ketoglutaric acid and amines such as NMDEA, THED, and BDMPP, the terpene hydroperoxides likely do not partition significantly into these phases, which can be expected to slow the reduction of the hydroperoxides to the corresponding alcohols and result in slower improvements in POV.

[0433] If the 2-oxo acid phase could be made more hydrophobic, it could potentially increase the partitioning of terpene hydroperoxides, and higher concentrations could result in faster reduction. However, if the 2-oxo acid phase is too hydrophobic, it will dissolve in the material being treated, such as citrus oil, and will no longer be maintained as a second phase. Fine-tuning the hydrophobicity of the 2-oxo acid phase can enable more efficient POV improvement while maintaining the improved material as a distinct second phase.

[0434] To achieve this, it may be possible to replace some of the active 2-oxoacids with bidentate, tridentate, or polydentate acids that are more hydrophobic than the 2-oxoacids. For this purpose, sebacic acid was used. Sebacic acid contains two carboxylic acid moieties connected by a linear eight-carbon chain. This unfunctionalized eight-carbon moiety suggests that sebacic acid is more hydrophobic than AKG. By varying the percentage of sebacic acid in the mixture, the overall hydrophobicity of the 2-oxoacid salt phase should be tunable.

[0435] Additionally, the bidentate amine THPED, which has more hydrophobic characteristics than THED, was used. THPED (also known as Neutrol TE® from BASF) has four additional methyl groups compared to THED. These four methyl groups also impart a higher hydrophobicity to the amine moiety.

[0436] [Table 65]

[0437] Salt Preparation Procedure: To each vial filled with AKG and sebacic acid ("SA"), anhydrous acetone was added (approximately 13 mL for AST-1 and 2, and 25 mL for AST-3, since SA has a relatively lower solubility in acetone than AKG). The mixture was vortexed. A small amount of white solid, likely an impurity in AKG, did not completely dissolve and settled to the bottom of the vial. The upper, clear solution was added all at once to the amine solution (0.01 mol in 5 mL of acetone). The opaque white emulsion was vortexed vigorously for approximately 1 minute, during which time a second phase coalesced. The mixture was placed in a freezer overnight, during which time the lower phase thickened to a waxy solid. While still cold, the upper layer was decanted and discarded. Residual acetone was removed from the lower product layer with a nitrogen stream, followed by treatment in a vacuum oven at room temperature for approximately 10 days.

[0438] Mixed citrus oil treatment: 5 mL of mixed citrus oil was added to a vial filled with approximately 0.2 g of AKG disalts (AST1-AST3 above). The mixture was vortexed for 1 minute and allowed to stand on the benchtop under ambient laboratory light and temperature. POV measurements were taken as a function of time after addition. The salts did not dissolve in the oil and precipitated as a mobile liquid at the bottom of the vial. The results are shown in the table below and in Figures 59-64.

[0439] AST-1:AKG (95%)-SA (5%) + THPED: [a cross-linked diammonium salt made from α-ketoglutaric acid (95%, AKG, CAS No. 328-50-7) and sebacic acid (5%, SA, CAS No. 111-20-6) and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 9.5:0.5:10] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 6-day period. The results are shown in the table below and in Figures 59 and 60.

[0440] [ka]

[0441] [Table 66]

[0442] AST-2: AKG (90%) - SA (10%) + THPED: [a cross-linked diammonium salt made from α-ketoglutaric acid (90%, AKG, CAS No. 328-50-7) and sebacic acid (10%, SA, CAS No. 111-20-6) and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 9:1:10] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 6-day period. The results are shown in the table below and in Figures 61 and 62.

[0443] [ka]

[0444] [Table 67]

[0445] AST-3: AKG (80%) - SA (20%) + THPED: [a cross-linked diammonium salt made from α-ketoglutaric acid (80%, AKG, CAS No. 328-50-7) and sebacic acid (20%, SA, CAS No. 111-20-6) and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPED, CAS No. 102-60-3) in a molar ratio of 8:2:10] was used to reduce the POV of a blended citrus oil. POV measurements were performed over a 6-day period. The results are shown in the table below and in Figures 63 and 64.

[0446] [ka]

[0447] [Table 68]

[0448] Comparing the results from #5AKG-THED or #6AKG-THED (80%) + BDMPP (20%) above with each of the three materials containing sebacic acid / THPED, we see that the more hydrophobic active salt phase indeed provided faster hydroperoxide reduction / POV improvement. This was particularly true at the earliest time points of the experiment, with the difference being most pronounced at the shortest time point, averaging approximately 0.1 days. Compared to #7AKG-BDMPP, as expected, the difference caused by sebacic acid was less pronounced (BDMPP is more hydrophobic than THED, so the benefit of sebacic acid / THPED should be less). This data demonstrates that including a hydrophobic component in the active salt phase can result in faster, and in some cases more complete, hydroperoxide reduction. The hydrophobic component does not necessarily have to be a multidentate compound with all acid groups or all amine / basic groups; it can have a mixture of acidic and basic moieties, such as amino acids or their derivatives, e.g., N,N-dimethylphenylalanine, or hydrophobic proteins.

[0449] Example 33: Rheological measurements Rheological simple shear flow measurements were performed on some of the two reported oxoacid samples using an Anton Paar Modular Compact Rheometer MCR 302 with a parallel plate geometry (25 mm). All samples were analyzed at 25°C ± 0.2°C. Shear rates (γ) ranging from 0.001 to 10 1 / s were measured. · A viscosity η curve was generated using a ) sweep. The results are shown in Figures 65-67.

[0450] Karl Fischer titration was used to measure water content before and after a series of rheological measurements. The 2-oxoacid was loaded onto the rheometer stage, the parallel plate was lowered to a measuring distance of 1 mm, the sample was trimmed to remove excess sample not in contact with the stage and plate, and the experiment was initiated. Multiple analyses were performed on each sample. Five consecutive measurements were performed on the sample without lifting the parallel plate. After these five measurements, the parallel plate was lifted, and the sample was exposed to ambient air, humidity, and temperature in the laboratory at 15-minute intervals for up to 90 minutes. At 15-minute intervals, the sample was reanalyzed using the same rheological method. The viscosity of each sample decreased as the sample absorbed increasing amounts of water over the 90-minute exposure period. At the end of the 90 minutes, the sample was collected in a plastic cuvette, capped, and sealed with parafilm (to prevent further water absorption) for subsequent Karl Fischer titration analysis. The Karl Fischer titration table below shows the water content before and after the rheological measurements. These materials are clearly very hygroscopic, and to obtain meaningful comparative viscosity measurements, dry samples must be used. The results are shown in the table below.

[0451] [Table 69]

[0452] It is clear that all of these samples exhibit Newtonian behavior over the shear rate range studied. The slight variations in viscosity are not significant and may be due to small amounts of crystals in the samples. It is clear that various formulations aimed at increasing viscosity were successful, as they showed significant increases in viscosity (e.g., two orders of magnitude) at all shear rates studied.

[0453] Example 34: Preparation and testing of aqueous gel phases containing dissolved 2-oxoacid salts In this embodiment, because gels or molecular associations are not formed by the 2-oxoacid components being incorporated into the ionic network, it is not necessary to use bidentate 2-oxoacids such as α-ketoglutaric acid. Monodentate 2-oxoacids (those containing only one acidic moiety in the molecule), such as pyruvic acid or 2-oxovaleric acid, work as well, since they only need to dissolve in the aqueous gel formed from water, even when a gelling / thickening agent is used. It should also be possible to use water-insoluble 2-oxoacids, but they may form emulsions of active droplets encased in a rigid aqueous gel.

[0454] In this case, the gel is formed from materials that are inactive in improving POV but simply serve the purpose of creating a semi-solid aqueous phase in which the 2-oxoacid component can be dissolved, emulsified, or suspended. Any material that forms a gel within the aqueous phase is potentially usable, and gel-forming components include gelatin, various gums such as xanthan gum, alginate, agar, and synthetic polymers such as polyacrylic acid (Carbomers®).

[0455] Two examples are shown below, one gelatin-based and one xanthan gum-based.

[0456] Pig skin gelatin with AKG-NMDEA salt [a diammonium salt prepared from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9)]: Approximately 500 mg of pig skin gelatin, Type A, gel strength 300 (product number G2500 from Sigma-Aldrich Chemical Co.) was added to 20 mL of distilled water, and the mixture was warmed until a clear solution was formed. Once the gelatin solution had cooled to 48 °C, 2 mL was placed in a 15 mL vial, and 105 mg of AKG-NMDEA salt was dissolved therein. The solution was placed in a refrigerator, and a gel solidified at the bottom of the vial. Next, 10 mL of mixed citrus oil was added to the vial, forming a mobile liquid second phase above the solidified aqueous gelatin layer. A blank vial was also prepared from 10 mL of mixed citrus oil. When POV measurements were taken, both the treated and blank vials were stored on the laboratory benchtop for 7 days. The results are as follows, showing a 39.6% reduction in POV: Blank - 31.67 mmol / L Treated - 19.13 mmol / L

[0457] Xanthan gum with AKG-NMDEA salt [a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (NMDEA, CAS No. 105-59-9)]: Approximately 700 mg of xanthan gum was added to 20 mL of distilled water, and the mixture was stirred with a spatula until a uniform, thick gel was produced. 2 mL of the gel was placed in a 15 mL vial, and 110 mg of AKG-NMDEA salt was mixed into it until dissolved. Next, 10 mL of mixed citrus oil was added to the vial, forming a mobile, liquid second phase on top of the thick aqueous gel layer. A blank vial was also prepared from 10 mL of mixed citrus oil. Both the treated and blank vials were stored on the laboratory benchtop for 7 days when POV measurements were performed. The results are shown below, indicating a 45.8% reduction in POV. Blank - 31.67 mmol / L Treated - 17.17 mmol / L

[0458] Example 35: Stabilization of a model fragrance according to one embodiment presented herein with a diammonium salt made from α-ketoglutaric acid (AKG, CAS No. 328-50-7) and N-methyldiethanolamine (90%, NMDEA, CAS No. 105-59-9) In this example, the ability of α-ketoglutarate to replace the traditional antioxidant butylhydroxytoluene (BHT) as a stabilizer for fine fragrances was investigated.

[0459] BHT was used as a control and compared with α-ketoglutarate. BHT and α-ketoglutarate were added to perfume oils at three different concentrations (0.05%, 0.10%, and 0.25%) and mixed with a magnetic stirrer within 30 minutes.

[0460] Eau de Toilette ("EDT") formulations containing the test and control formulations were then prepared as follows: 10% (by weight) perfume oil concentrate, 10% (by weight) deionized water, 80% (by weight). The final concentrations of BHT or α-ketoglutarate in the EDT were 0.005%, 0.010%, and 0.025%.

[0461] The resulting EDT formulations were stored at 45°C for 2 months. After storage, samples of the EDT formulations were taken and analyzed by gas chromatography to determine the concentration of acetaldehyde diethyl acetal. The amount of acetaldehyde diethyl acetal is directly related to the general oxidation of EDT, since it is formed by the oxidation of ethanol according to the following reaction:

[0462] [ka]

[0463] The results are shown in the table below.

[0464] [Table 70]

[0465] The EDT formulation without BHT or α-ketoglutarate contained 150 ppm acetaldehyde diethyl acetal, and its odor was observed to be altered by oxidation during stability testing. This odor was typical of oxidized fragrances.

[0466] EDT formulations containing BHT (0.005% to 0.025% in EDT) were significantly less oxidized, with acetaldehyde diethyl acetal levels of 85 ppm for 0.025% BHT in EDT.

[0467] The EDT formulations containing α-ketoglutarate were further stabilized such that the concentration of acetaldehyde diethyl acetal was 10 ppm when 0.025% in the EDT and 33 ppm when 0.010% in the EDT.

[0468] Example 36: Determination of Rancid Aldehydes in Triglycerides After Treatment with at Least One α-Oxocarboxylic Acid Blank sample In all the following experiments, an untreated oil (blank) sample was kept. The blank was always packaged, stored, handled, and sampled exactly the same as the treated sample, except for the addition of the 2-oxoacid salt. In this way, the effect of atmospheric oxygen in the headspace volume will be similar. For example, the ratio of headspace volume to oil volume and the contact area between the headspace and the oil surface will be the same for treated and untreated samples.

[0469] Sensory evaluationPhenylpyruvic acid and pyruvic acid and their salts each possess an aroma that is slightly acidic in nature. Conversely, α-ketoglutaric acid or its salts lack such an aroma. The flavorists who performed the sensory evaluations noted that this acidic aroma created some confusion in the assessment of oil rancidity, especially when the rancidity was not significant. The effect was likely to be an overestimation of the rancidity of oils containing phenylpyruvic acid or pyruvic acid, especially in the early stages of the experiment before the flavorists had acquired the ability through experience to more clearly distinguish between oxoacid aroma and rancidity. α-Ketoglutarate, which has no odor, did not produce such an overestimation. This overestimation phenomenon likely played a role in some instances where sensory rankings did not correlate well with HPLC aldehyde data. The correlation of the sensory HPLC data was much stronger in the case of α-ketoglutarate.

[0470] Low oleic sunflower oil: Treatment of low oleic sunflower oil with PhPA-DiMeC10A [ammonium salt prepared from phenylpyruvic acid and N,N-dimethyldecylamine in a 1:1 molar ratio]: [ka]

[0471] A 30 mL glass vial was charged with 15 mL of low oleic sunflower oil, freshly purchased from a local supermarket, opened 44 days prior, and kept at room temperature. To this vial, 0.3001 g of PhPA-DiMeC10A was added. Most of the salt dissolved, but some undissolved solid remained. The mixture was allowed to stand on the benchtop at room temperature in ambient laboratory light. Periodically, measurements of POV by titration, rancidity aldehydes by HPLC with DNPH derivatization (see methods below), and sensory evaluation were recorded. The results are shown below: [Table 71]

[0472] The data show that treatment was very rapid and effective, but at some point between the 35 and 76 day time points, PhPA-DiMeC10A appears to be depleted. Once depletion occurred, the treated samples began to autoxidize like the untreated samples, but the improvement is still dramatic.

[0473] HPLC data: Sample preparation (dinitrophenylhydrazine [DNPH] derivatization): DNPH derivatives of the aldehyde / ketone products in the oxidized oil and treated oxidized oil were synthesized as follows: Approximately 0.500 g of triglycerides was diluted to 12 mL by adding propan-2-ol (IPA). 1 mL of this diluted oil mixture was added to 1 mL of diluted DNPH solution, which was prepared separately by mixing DNPH (3 g / L in IPA) with 3% aqueous HCl and then diluted to 12 mL with propan-2-ol (IPA). The reaction vial was stirred and held at 40°C for 1 hour to accelerate the derivatization reaction. The reaction mixture was then cooled to room temperature, neutralized with 20% trimethylamine in IPA, and centrifuged at 5000 rpm for 5 minutes. The supernatant was then injected for HPLC analysis as follows: HPLC analysis method: An Agilent 1100 series HPLC system equipped with a diode array detector was used.

[0474] Column: Phenomenex Luna C18 (2) columns (250 x 4.6 mm, 5 μm) Column temperature: 30℃ Flow rate: 0.8mL / min Injection volume: 5μL Detection: UV absorbance at 250, 300, 366 and 385 nm [Table 72]

[0475] [Table 73]

[0476] [Table 74]

[0477] [Table 75]

[0478] [Table 76]

[0479] Treatment of low oleic sunflower oil with PA-NMDEA [ammonium salt prepared from pyruvic acid and N-methyldiethanolamine in a 1:1 molar ratio]: [ka]

[0480] A 30 mL glass vial was charged with 10 mL of low oleic sunflower oil, freshly purchased from a local supermarket, opened 50 days prior, and kept at room temperature. To this vial, 0.2002 g of PA-NMDEA was added. Most of the salt dissolved. The mixture was allowed to stand on the benchtop at room temperature under ambient laboratory light. Periodically, measurements of POV by titration, rancidity aldehydes by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 77]

[0481] HPLC Data: Sample preparation (DNPH derivatization): As above.

[0482] [Table 78]

[0483] [Table 79]

[0484] Sensory data: Sensory evaluation index criteria: As above [Table 80]

[0485] Treatment of low oleic sunflower oil with AKG-DiMeC12A [ammonium salt prepared from α-ketoglutaric acid and N,N-dimethyldodecylamine in a molar ratio of 1:2] [ka]

[0486] A 30 mL glass vial was charged with 10 mL of low oleic sunflower oil, freshly purchased from a local supermarket, opened 50 days prior, and kept at room temperature. To this vial, 0.2400 g of AKG-DiMeC12A was added. The salt did not completely dissolve, but a cloudy, gel-like suspension resulted. The mixture was allowed to stand on the benchtop at room temperature under ambient laboratory light. Periodically, measurements of POV by titration, rancidity aldehydes by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 81]

[0487] The data show that the treatment was rapid and effective, but at some point between the 29 and 76 day time points, the AKG-DiMeC12A appears to be depleted. Once depletion occurred, the treated samples began to autoxidize like the untreated samples, but the improvement is still dramatic.

[0488] HPLC data: Sample preparation (DNPH derivatization): As above [Table 82]

[0489] [Table 83]

[0490] Sensory data: Sensory evaluation index criteria: As above [Table 84]

[0491] High Oleic Sunflower Oil: Treatment of high oleic sunflower oil with PhPA-DiMeC10A [ammonium salt prepared from phenylpyruvic acid and N,N-dimethyldecylamine in a 1:1 molar ratio]: [ka]

[0492] A 30 mL glass vial was charged with 15 mL of unopened high oleic sunflower oil that had been stored in a plastic bottle at room temperature. To this vial, 0.301 g of PhPA-DiMeC10A was added. Most of the salt dissolved, but some undissolved solid remained. The mixture was left to stand on the benchtop at room temperature under ambient laboratory light. Periodically, POV measurements by titration, rancidity aldehyde measurements by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 85]

[0493] HPLC data: Sample preparation (DNPH derivatization): As above.

[0494] [Table 86]

[0495] [Table 87]

[0496] Sensory data: Sensory evaluation index criteria: As above [Table 88]

[0497] Treatment of high oleic sunflower oil with PA-NMDEA [ammonium salt prepared from pyruvic acid and N-methyldiethanolamine in a 1:1 molar ratio]: [ka]

[0498] A 30 mL glass vial was charged with 15 mL of unopened high oleic sunflower oil that had been stored in a plastic bottle at room temperature. To the vial, 0.3002 g of PA-NMDEA was added. Most of the salt dissolved. The mixture was left to stand on the benchtop at room temperature under ambient laboratory light. Periodically, POV measurements by titration, rancidity aldehyde measurements by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 89]

[0499] HPLC data: Sample preparation (DNPH derivatization): As above.

[0500] [Table 90]

[0501] [Table 91]

[0502] Sensory data: Sensory evaluation index criteria: As above [Table 92]

[0503] Treatment of high oleic sunflower oil with AKG-DiMeC12A [ammonium salt prepared from α-ketoglutaric acid and N,N-dimethyldodecylamine in a molar ratio of 1:2] [ka]

[0504] A 30 mL glass vial was charged with 15 mL of unopened high oleic sunflower oil that had been stored in a plastic bottle at room temperature. To this vial, 0.302 g of AKG-DiMeC12A was added. The salt did not completely dissolve, but a cloudy, gel-like suspension was obtained. The mixture was left to stand on the benchtop at room temperature under ambient laboratory light. Periodically, measurements of POV by titration, rancidity aldehydes by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 93]

[0505] HPLC data: Sample preparation (DNPH derivatization): As above.

[0506] [Table 94]

[0507] [Table 95]

[0508] Sensory data: Sensory evaluation index: As above [Table 96]

[0509] Soybean oil: Treatment of soybean oil with PhPA-DiMeC10A [ammonium salt prepared from phenylpyruvic acid and N,N-dimethyldecylamine in a molar ratio of 1:1]: [ka]

[0510] A 30 mL glass vial was charged with 15 mL of soybean oil that had been stored in a plastic bottle at room temperature but had not been opened. To this vial, 0.301 g of PhPA-DiMeC10A was added. Most of the salt dissolved, but some undissolved solid remained. The mixture was left on the benchtop at room temperature in ambient laboratory light. Periodically, POV measurements by titration, rancidity aldehyde measurements by HPLC with DNPH derivatization (see methods above), and sensory evaluations were recorded. The results are shown below: [Table 97]

[0511] HPLC data: Sample preparation (DNPH derivatization): As above.

[0512] [Table 98]

[0513] [Table 99]

[0514] Sensory data: Sensory evaluation index criteria: As above [Table 100]

[0515] Treatment of soybean oil with PA-NMDEA [ammonium salt prepared from pyruvic acid and N-methyldiethanolamine in a molar ratio of 1:1]: [ka]

[0516] A 30 mL glass vial was charged with 15 mL of soybean oil that had been stored in a plastic bottle at room temperature but had not been opened. To this vial, 0.3002 g of PA-NMDEA was added. Most of the salt dissolved. The mixture was left to stand on the benchtop in ambient laboratory light at room temperature. Periodically, POV measurements by titration, rancidity aldehyde measurements by HPLC with DNPH derivatization (see methods above), and sensory evaluations were recorded. The results are shown below: [Table 101]

[0517] HPLC Data: Sample preparation (DNPH derivatization): As above.

[0518] [Table 102]

[0519] [Table 103]

[0520] Sensory data: Sensory evaluation index criteria: As above [Table 104]

[0521] Treatment of soybean oil with AKG-DiMeC12A [ammonium salt prepared from α-ketoglutaric acid and N,N-dimethyldodecylamine in a molar ratio of 1:2] [ka]

[0522] A 30 mL glass vial was charged with 15 mL of soybean oil that had been stored in a plastic bottle at room temperature but had not been opened. To this vial, 0.302 g of AKG-DiMeC12A was added. The salt did not completely dissolve, but a cloudy, gel-like suspension was obtained. The mixture was left to stand on the benchtop in ambient laboratory light at room temperature. Periodically, measurements of POV by titration, rancidity aldehydes by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 105]

[0523] HPLC data: Sample preparation (DNPH derivatization): As above.

[0524] [Table 106]

[0525] [Table 107]

[0526] Sensory data: Sensory evaluation index criteria: As above [Table 108]

[0527] Extra virgin olive oil: Treatment of extra virgin olive oil with PhPA-DiMeC10A [ammonium salt prepared from phenylpyruvic acid and N,N-dimethyldecylamine in a molar ratio of 1:1]: [ka]

[0528] A 30 mL glass vial was charged with 15 mL of unopened extra virgin olive oil that had been stored at room temperature in a brown glass bottle. To this vial, 0.301 g of PhPA-DiMeC10A was added. Most of the salt dissolved, but some undissolved solid remained. The mixture was left on the benchtop at room temperature in ambient laboratory light. Periodically, POV measurements by titration, rancidity aldehyde measurements by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 109]

[0529] HPLC data: Sample preparation (DNPH derivatization): As above.

[0530] [Table 110]

[0531] [Table 111]

[0532] Sensory data: Sensory evaluation index criteria: As above [Table 112]

[0533] Treatment of extra virgin olive oil with AKG-DiMeC12A [ammonium salt prepared from α-ketoglutaric acid and N,N-dimethyldodecylamine in a molar ratio of 1:2] [ka]

[0534] A 30 mL glass vial was charged with 15 mL of unopened extra virgin olive oil that had been stored at room temperature in a brown glass bottle. To this vial, 0.302 g of AKG-DiMeC12A was added. The salt did not completely dissolve, but a cloudy, gel-like suspension was obtained. The mixture was left to stand on the benchtop at room temperature in ambient laboratory light. Periodically, POV measurements by titration, rancidity aldehyde measurements by HPLC with DNPH derivatization (see methods above), and sensory evaluations were recorded. The results are shown below: [Table 113]

[0535] HPLC data: Sample preparation (DNPH derivatization): As above.

[0536] [Table 114]

[0537] [Table 115]

[0538] Sensory data: Sensory evaluation index criteria: As above [Table 116]

[0539] Treatment of Formulated Ranch Salad Dressing: Treatment of salad dressing with PhPA-DiMeC10A [ammonium salt prepared from phenylpyruvic acid and N,N-dimethyldecylamine in a 1:1 molar ratio]: A 30 mL glass vial was charged with 15 g of a commercially available salad dressing that had been opened and stored at room temperature in the laboratory for an unknown but extended period of time. To the vial, 0.4002 g of PhPA-DiMeC10A was added and mixed well. The mixture was allowed to stand on the benchtop at room temperature under ambient laboratory light. Periodically, measurements of POV by titration, rancidity aldehydes by HPLC with DNPH derivatization (see methods above), and sensory evaluation were recorded. The results are shown below: [Table 117]

[0540] HPLC data: Sample preparation (DNPH derivatization): As above.

[0541] [Table 118]

[0542] [Table 119]

[0543] Sensory data: Sensory evaluation index criteria: As above [Table 120]

[0544] Example 37: Reduction of POV and Rancidity in Soap Formulations According to an Embodiment Presented herein Using a Diammonium Salt Formed by the Reaction of Phenylpyruvic Acid and N,N-Dimethyldecylamine (Herein Referred to as DiMeC10A-PhPA) The degree of rancidity in the tested soap formulations was determined by measuring the content of aldehyde and ketone reaction products of the soap oil present. DNPH derivatives of the aldehyde / ketone products in the soap and treated soap were synthesized as follows: 0.1000 g of either the DiMeC10A-PhPA-treated or untreated soap formulation was separately measured and diluted to 12 mL by adding propan-2-ol. 1 mL of this diluted mixture was added to 1 mL of diluted DNPH solution, which was separately prepared by mixing DNPH (3 g / L) with 3% HCl and diluting to 12 mL by adding propan-2-ol. The reaction vial was stirred and kept at 40°C for 1 hour to accelerate the derivatization reaction. It was then cooled to room temperature, neutralized with 20% triethylamine, and centrifuged at 5000 rpm for 5 minutes. The sample was then injected into an HPLC column. The results are shown in the table below: [Table 121]

[0545] These data suggest that treating soap formulations with DiMeC10A-PhPA improves or reduces rancidity by reducing the amount of aldehyde and ketone reaction products in the soap oil. The sensory properties of the treated and untreated soap formulations are shown below.

[0546] [Table 122]

[0547] Example 38: Reduction of POV in a model citrus flavor according to one embodiment presented herein using either L-cysteine ​​ethyl ester hydrochloride, N-acetylcysteine ​​methyl ester, or glutathione Without intending to be limited to any particular theory, reduced sulfur compounds such as thiols can readily react with hydroperoxides, thereby reducing them, most likely to the corresponding alcohols. Many low-molecular-weight thiols, such as ethanethiol, have a very malodorous odor and may be unsuitable for use in perfumed products or foods. However, certain thiol compounds are non-malodorous and can be used satisfactorily. Such compounds include thiols derived from amino acids and / or peptides, such as cysteine ​​derivatives (e.g., cysteine ​​ethyl ester hydrochloride, N-acetylcysteine ​​methyl ester, and glutathione).

[0548] Treatment of Model Fragrances: Model mixed citrus fragrances (15 mL in each of three 16 mL vials) were treated with sulfur-containing compounds (approximately 0.15 g each, see list below). The vials were left on the benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. A brownish discoloration was observed for the samples treated with L-cysteine ​​ethyl ester hydrochloride. The results are shown in the table below. The POV of the untreated model fragrance was 5.55 mmol / L.

[0549] [Table 123]

[0550] Example 39: Reduction of POV in a model citrus flavor or blended citrus oil according to one embodiment presented herein using either 2-phospho-L-ascorbic acid trisodium salt (Vc-PTNa) or L-ascorbic acid 2-phosphate sesquimagnesium salt hydrate (Vc-PSeMg) Without intending to be limited to a particular theory, ascorbic acid and its esters, such as ascorbyl palmitate, are widely used antioxidants in many applications.However, in fine fragrances, home care products, skin care products, and other cosmetics, this tends to cause discoloration problems.The phosphorylated form of ascorbic acid is used in skin care products to provide the cosmeceutical benefits of topical application of vitamin C without the problem of discoloration.Here, phosphorylated ascorbic acid analogs are used to reduce the POV of mixed citrus oils and model citrus fragrances.

[0551] Model Flavor Treatment: Model citrus flavors (15 mL each in 16 mL vials, YIWA-1702, pg 61) were treated with ascorbate (approximately 0.15 g each, see table below) and measured by POV titration. All ascorbate dissolved in the model citrus flavor, resulting in a nearly clear yellow solution, similar to the untreated version. These solutions, both treated and untreated, were left undisturbed on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. No color change occurred for any of the treated samples throughout the duration of the experiment.

[0552] Treatment of combined citrus oils: Mixed citrus oils (9 mL each in separate vials) were treated with the phosphate ascorbates listed above (approximately 0.35 g each). The oils, both treated and untreated, were left on the benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. No color change was observed for any of the treated samples throughout the duration of the experiment.

[0553] [Table 124]

[0554] The results are shown in the table below and in Figures 68-75.

[0555] [Table 125]

[0556] [Table 126]

[0557] [Table 127]

[0558] [Table 128]

[0559] Example 40: Reduction of POV in a model citrus flavor or blended citrus oil using either dimethylethylsilane (DMESi), pentamethyldisiloxane (PMDSi), methylhydrogensiloxane polymer (PMHS), or methylhydrogensiloxane polymer (PMHS) according to one embodiment presented herein Treatment of Model Fragrances: Model citrus fragrances (15 mL in each of four 16 mL vials) were treated with the test compounds (approximately 0.3 g each; only PMMDSiH was miscible with the fragrance, the other three were not). Treated and untreated fragrances were left undisturbed on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. No color change was observed for any of the treated samples over the course of the experiment.

[0560] Treatment of combined citrus oil: The combined citrus oil (6 mL in each of four separate 9 mL vials) was treated with test compounds (approximately 0.2 g each; all demonstrated miscibility with the citrus oil). Treated and untreated samples were placed on a benchtop in ambient laboratory light at room temperature, and POV measurements were taken periodically. No color change was observed for any of the treated samples during the treatment period.

[0561] [Table 129]

[0562] For the mixed citrus oil, 5 mL + approximately 200 mg of Si compound was used, resulting in approximately 40 mg / mL. For the model citrus flavor, 15 mL + approximately 300 mg of Si compound was used, resulting in approximately 20 mg / mL.

[0563] The results are shown in the table below and in Figures 76-91.

[0564] [Table 130]

[0565] [Table 131]

[0566] [Table 132]

[0567] [Table 133]

[0568] [Table 134]

[0569] [Table 135]

[0570] [Table 136]

[0571] [Table 137]

[0572] Example 41: Reduction of POV in a model citrus flavor according to one embodiment presented herein using either glyoxylic acid or diethyl oxaloacetate sodium salt Treatment of Model Fragrance: Model citrus fragrance (15 mL in each of four 16 mL vials) was treated with the test compound. The treated and untreated fragrances were left on the benchtop at room temperature in ambient laboratory light and POV measurements were taken periodically. No color change was observed over the test period for any of the treated samples. The results are shown in the table below. The starting POV for the untreated model fragrance was 5.55 mmol / L.

[0573] [Table 138]

[0574] Example 42: Reduction of POV in blended citrus oils according to one embodiment presented herein using either monobutyl oxalate (2-butoxy-2-oxoacetic acid) or monobenzyl oxalate (2-(benzyloxy)-2-oxoacetic acid) Treatment of combined citrus oil: The combined citrus oil (6 mL in each of two 8 mL vials) was treated with oxalic acid monoester (approximately 0.12 g). Both the treated and untreated samples were left on the benchtop at room temperature under ambient laboratory light, and POV measurements were taken periodically. Both compounds were soluble in the combined citrus oil. Due to the significantly higher POV of the untreated oil, 0.5 mL of oil was used for each titration instead of the usual 1 mL sample size. The results are shown in the table below and in Figures 92-95.

[0575] [Table 139]

[0576] [Table 140]

[0577] [Table 141]

[0578] Example 43: Reduction of POV in autoxidized limonene oil according to one embodiment presented herein using N(3),N(3),N(5),N(5),2,6-hexamethyl-1,4-dihydro-3,5-pyridinedicarboxamide (HDPA, CHNO, MW=251.331) Without intending to be limited to a particular theory, 1,4-dihydropyridines are known to act as reducing agents in biological systems (e.g., NADH; the reduced form of nicotinamide adenine dinucleotide). This example demonstrates that this heterocyclic ring system non-enzymatically prevents the increase in POV of limonene autoxidation.

[0579] HDPA: N(3),N(3),N(5),N(5),2,6-hexamethyl-1,4-dihydro-3,5-pyridinedicarboxamide (HDPA, C 13 H 21 N3O2, MW=251.331) [ka]

[0580] Preparation of Treated Samples: Oxidized limonene (100 μL, with a starting POV of approximately 38 mmol / L) was treated with 2 mg of HDPA (approximately 2 equivalents of HP). The treated and untreated limonene samples were left on the benchtop under ambient laboratory light at room temperature, and HPLC chemiluminescence measurements were taken periodically. An equal amount of untreated limonene was prepared in a second vial and monitored in the same way as the treated vial for comparison. The results are shown in the table below and in Figure 96.

[0581] [Table 142]

[0582] Example 44: Hydrolyzable esters of 2-oxoacids and / or oxalic acid to reduce POV by hydrolysis of the ester moiety resulting in controlled and / or extended in situ release of 2-oxoacids, oxalic acid monoesters, or oxalic acid This study demonstrates the use of hydrolyzable esters of 2-oxoacids and / or oxalic acid to reduce POV through hydrolysis of the ester moiety, resulting in controlled and / or extended in situ release of the 2-oxoacid, oxalic acid monoester, or oxalic acid itself. 2-oxoacids and oxalic acid are very strong acids that can cause damage to fragrances and / or formula ingredients if added all at once in high concentrations without buffering. Controlled release prevents such damage.

[0583] The 2-oxoacid esters or oxalic acid esters serve as non-acidic sources of the original 2-oxoacids, oxalic acid monoesters, or oxalic acid itself. These esters release the 2-oxoacids, oxalic acid monoesters, or oxalic acid at a controlled rate through hydrolysis induced by water in the treated material. This requires some water in the treated material. The liberated 2-oxoacids, oxalic acid monoesters, or oxalic acid react with harmful hydroperoxides present in the treated material, usually as a result of autoxidation, and chemically consume them through oxidative decarboxylation. The hydroperoxides ultimately convert to the structurally corresponding alcohols, which are relatively harmless.

[0584] The following compounds were tested as follows: [Table 143]

[0585] Preparation of citrus model flavor (mixed citrus oils in 90 / 10 v / v EtOH / water): 360 mL EtOH (flavor grade or HPLC grade) + 40 mL demineralized water + 80 mL mixed citrus oils. Concentration: 80 mL / 480 mL = 16.67% v / v. This resulted in a slightly cloudy yellow solution.

[0586] Citrus flavor treatment (10mg / mL): Model citrus flavors (40 mL aliquots, each in separate 40 mL vials) were treated with Compounds 1 and 6 (approximately 0.4 g each) by simply mixing and dissolving the treatment compounds. The treated and untreated solutions were left on a benchtop at room temperature in ambient laboratory light, and POV measurements were taken periodically. The color change of the samples was also monitored throughout the experiment.

[0587] A separate experiment was performed for AKG-diEtO (compound 7): a model citrus flavor (22 mL in a 36 mL vial) was treated with AKG-diEtO (approximately 0.23 g) and monitored according to the procedure described above for POV measurements.

[0588] Plots of POV versus time are shown for di-n-butyl α-ketoglutarate (Figure 97), di-tert-butyl α-ketoglutarate (Figure 99), dibenzyl α-ketoglutarate (Figure 100), dimethyl oxalate (Figure 101), and dibutyl oxalopropionate (Figure 105).

[0589] Plots of % POV reduction versus time are shown for di-n-butyl α-ketoglutarate (Figure 98), dimethyl oxalate (Figure 102), dibutyl oxalate (Figure 104), diethyl oxalopropionate (Figure 106), and diethyl α-ketoglutarate (Figure 108).

[0590] While various aspects of the present invention have been illustrated above by reference to examples and preferred embodiments, it will be understood that the scope of the present invention is defined not by the foregoing description but rather by the following claims, appropriately interpreted under the principles of patent law.

Claims

1. 1. A method for reducing or improving POV of a citrus flavor or citrus oil as a flavor ingredient, the method comprising: a. adding at least one modifier which is a thiol to the citrus flavor or citrus oil having a first POV level, wherein the thiol is selected from the group consisting of glutathione, N-acetylcysteine ​​methyl ester, and cysteine ​​ethyl ester hydrochloride; b. mixing or contacting said at least one modifier with said citrus flavor or citrus oil for a time sufficient to reduce said first POV level to a predetermined second lower level; A method comprising:

2. 10. The method of claim 1, wherein the citrus oil is processed prior to incorporation into the fragrance.

3. 10. The method of claim 1, wherein the citrus oil is treated after incorporation into the fragrance.

4. 10. The method of claim 1, wherein the concentration of the at least one modifier ranges from 0.001 to 10% by weight after addition to the combined citrus flavor and citrus oil.

5. 2. The method of claim 1, wherein the predetermined second lower level is between 5 and 20 mmol / L.

6. 2. The method of claim 1, wherein the predetermined second lower level is 0 to 6 mmol / L.

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