Mixed composition containing glycolipid and triethyl citrate

Abstract

The present invention relates to compositions comprising glycolipid and triethyl citrate (TEC).

Description

[Technical Field]

[0001] The present invention relates to a composition comprising glycolipid and triethyl citrate (TEC). [Background technology]

[0002] Rhamnolipide is an anionic surfactant with unique properties such as cleansing properties, biodegradability, and strong foaming ability. The commercial availability of rhamnolipide has increased over the past few years across various application areas. In cosmetic applications, the foaming ability of rhamnolipide is of particular interest. Rapid flash foaming and high foam volume indicate to consumers that the product is of effective quality. In any case, the foaming behavior of rhamnolipide depends on the pH value of the formulation. Ozdemir et al. have described the effect of pH on surface and interface behavior (Colloids Surf. A2004, 234, 135-143). One drawback of the behavior described in the technical standards is the fact that a pH of up to pH 7 is required for rapid foam generation. At lower pH levels, foaming ability decreases. Cosmetic compositions are typically formulated at pH levels below 7 or down to values ​​such as pH 5. Here, the foaming ability of rhamnolipide decreases significantly.

[0003] To overcome this problem, additives may be applied. Nonionic surfactants, such as fatty acid alkanolamides, are available on the market as foaming agents. These substances may contain trace amounts of nitrosamines, and they are also based on tropical vegetable oils. WO2001010391A2 describes the use of alkoxylated carboxylic acid esters as foaming agents. The alkoxylation process yields measurable levels of 1,4-dioxane, which is an undesirable by-product in cosmetic applications.

[0004] In the cosmetics and personal care fields, triethyl citrate is used as a fragrance fixative and as a coating agent in hairsprays and nail polishes. It is also used as an active ingredient in deodorants.

[0005] Triethyl citrate is used, for example, as a foaming aid for egg whites, and particularly as a food additive (E number E1505) to stabilize albuminic foam. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] WO2001010391A2 [Non-patent literature]

[0007] [Non-Patent Document 1] Colloids Surf. A2004, 234, 135-143 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The object of the present invention was to provide a composition having improved foaming properties of rhamnolipid, particularly in an acidic environment, at pH values ​​widely used in cosmetics. [Means for solving the problem]

[0009] Surprisingly, it has been found that the mixed compositions described below can achieve the objectives addressed by the present invention.

[0010] One advantage of the mixed compositions according to the present invention is their excellent foaming properties.

[0011] A further advantage of the mixed compositions according to the present invention is their outstanding flash foaming under aqueous conditions.

[0012] A further advantage of the mixed compositions according to the invention is their very high foam volume under aqueous conditions.

[0013] A further advantage of the mixed compositions according to the invention is their low viscosity and thus their simple processability in any desired aqueous surfactant system.

[0014] A further advantage of the mixed compositions according to the invention is their good skin and hair cleansing properties.

[0015] A further advantage of the mixed compositions according to the invention is their very good solubilizing effect on essential oils at low usage levels.

[0016] A further advantage of the mixed compositions according to the invention is their mildness and good physiological compatibility, which is characterized in particular by high values in the erythrocyte hemolysis test (RBC).

[0017] A further advantage of the mixed compositions according to the invention is their good skin feel during and after washing.

[0018] A further advantage of the mixed compositions according to the invention is that they leave a smooth and soft skin feel after washing.

[0019] A further advantage of the mixed compositions according to the invention is that they can be synthesized without containing petrochemical raw materials.

[0020] A further advantage of the mixed compositions according to the invention is that they can be synthesized without containing important raw materials such as tropical vegetable oils.

[0021] A further advantage of the mixed compositions according to the invention is their excellent microbiological stability.

[0022] A further advantage of the mixed composition according to the present invention is that its dependence on pH for foaming is reversed compared to pure glycolipids, particularly rhamnolipids.

[0023] A composition comprising 0.2 to 70% by weight, preferably 0.4 to 55% by weight, of at least one glycolipid, 0.01 to 14% by weight, preferably 0.02 to 11% by weight, of triethyl citrate, and water, wherein the weight percentages are based on the entire composition, and the weight ratio of all glycolipids to all triethyl citrate contained in the composition is in the range of 5:1 to 20:1, preferably 6:1 to 15:1, and particularly preferably 7:1 to 12:1. [Modes for carrying out the invention]

[0024] In relation to this invention, "pH" is defined as the value measured for the relevant composition at 25°C after stirring for 5 minutes using a pH electrode calibrated according to ISO 4319 (1977).

[0025] In the context of this invention, the term "preservative" is understood to mean an agent that protects against the growth of microorganisms, particularly bacteria.

[0026] In relation to the present invention, the term "aqueous" is understood to mean a composition containing at least 5.0% by weight of water, based on the total composition considered.

[0027] Unless otherwise specified, all percentages (%) listed are percentages based on mass.

[0028] Preferred compositions according to the present invention include rhamnolipid, glucolipid and sophorolipid, and in particular rhamnolipid and glucolipid, and most particularly rhamnolipid, glycolipid selected from the group.

[0029] In the context of this invention, the term "rhamnolipide" also includes rhamnolipide, its protonated forms, and especially its salts.

[0030] In the context of this invention, the term "rhamnolipide" is understood to mean, in particular, a mixture of compounds of general formula (I) and their salts. [ka] Here, m=2, 1, or 0, n=1 or 0, R 1 and R 2 These are organic groups having 2 to 24, preferably 5 to 13, carbon atoms, independently of each other, and identical or different, and are in particular optionally branched, optionally substituted, especially hydroxysubstituted, optionally unsaturated, especially optionally monounsaturated, diunsaturated, or triunsaturated alkyl groups, preferably pentenyl, heptenyl, nonenyl, undecenyl, and tridecenyl, and (CH2) o -CH3 (where o = 1 to 23, preferably 4 to 12) is selected from the group.

[0031] When n=1, the glycosidic bond between the two rhamnose units is preferably in the α configuration. The optically active carbon atom of the fatty acid is preferably present as an R-enantiomer (e.g., (R)-3-{(R)-3-[2-O-(α-L-rhamnopyranosyl)-α-L-rhamnopyranosyl]oxydecanoyl}oxydecanoate).

[0032] In the context of this invention, the term "diramnolipide" is understood to mean a compound of general formula (I) or a salt thereof, where n=1.

[0033] In the context of this invention, the term "monorhamnolipide" is understood to mean a compound of general formula (I) or a salt thereof, where n=0.

[0034] Individual ramnolipids are abbreviated according to the following nomenclature. "diRL-CXCY" is understood to mean a diramnolipid of general formula (I), where R 1 group and R 2 group, one of which is (CH2) o -CH3, o = X - 4, and R 1 group or the remainder of the R 2 group is (CH2) o -CH3, o = Y - 4. "monoRL-CXCY" is understood to mean a monoramnolipid of general formula (I), where R 1 group and R 2 group, one of which is (CH2) o -CH3, o = X - 4, and R 1 group or the remainder of the R 2 group is (CH2) o -CH3, o = Y - 4.

[0035] Therefore, the nomenclature used has no difference between "CXCY" and "CYCX". For ramnolipids with m = 0, monoRL-CX or diRL-CX is used accordingly.

[0036] If one of the above indices X and / or Y has ":Z" attached, this means that the respective R 1 group and / or R 2 group is an unbranched and unsubstituted hydrocarbon group with X - 3 or Y - 3 carbon atoms having a Z double bond.

[0037] To determine the ramnolipid content in the context of the present invention, only the mass of the anion of the ramnolipid, for example, "one hydrogen subtracted from general formula (I)", is considered.

[0038] To determine the ramnolipid content in the context of the present invention, all ramnolipids are converted to the protonated form (refer to general formula (I)) by acidification and quantified by HPLC.

[0039] According to the present invention, the composition preferably contains 51 to 95% by weight, preferably 70 to 90% by weight, and particularly preferably 75 to 85% by weight of diRL-C10C10, where the weight percentage is based on the total amount of all present rhamnolipids.

[0040] According to the present invention, the composition preferably contains 0.5 to 9% by weight, preferably 0.5 to 3% by weight, and particularly preferably 0.5 to 2% by weight of monoRL-C10C10, where the weight percentage is based on the total of all present rhamnolipids.

[0041] A preferred composition according to the present invention is characterized in that the weight ratio of all diramnolipide present to all monoramnolipide present is greater than 51:49 (>51:49), particularly greater than 91:9, preferably greater than 97:3, and especially preferably greater than 98:2.

[0042] According to the present invention, the composition preferably contains 0.5 to 25% by weight, preferably 5 to 15% by weight, and particularly preferably 7 to 12% by weight of diRL-C10C12, where the weight percentage is based on the total amount of all rhamnolipids present.

[0043] According to the present invention, the composition comprises 0.1 to 5% by weight, preferably 0.5 to 3% by weight, particularly preferably 0.5 to 2% by weight of monoRL-C10C12, and / or preferably 0.1 to 5% by weight, preferably 0.5 to 3% by weight, particularly preferably 0.5 to 2% by weight of monoRL-C10C12:1, where the weight percentage is based on the total of all present rhamnolipids.

[0044] A particularly preferred composition according to the present invention preferably contains 0.5 to 15% by weight, preferably 3 to 12% by weight, and especially preferably 5 to 10% by weight of diRL-C10C12:1, 0.5 to 25% by weight, preferably 5 to 15% by weight, and especially preferably 7 to 12% by weight of diRL-C10C12, 0.1 to 5% by weight, preferably 0.5 to 3% by weight, and especially preferably 0.5 to 2% by weight of monoRL-C10C12, and 0.1 to 5% by weight, preferably 0.5 to 3% by weight, and especially preferably 0.5 to 2% by weight of monoRL-C10C12:1, wherein the weight percentages are based on the total amount of all present rhamnolipids.

[0045] In relation to the present invention, the term "glucoripide" is understood to mean a compound of general formula (II) or a salt thereof. [ka] Here, R 1b and R 2b These are, independently of each other, identical or different organic groups having 2 to 24 carbon atoms, particularly optionally branched, optionally substituted, particularly hydroxysubstituted, optionally unsaturated, particularly optionally monounsaturated, diunsaturated, or triunsaturated alkyl groups, preferably pentenyl, heptenyl, nonenyl, undecenyl, and tridecenyl, and (CH2) p It is selected from the group consisting of CH3 (where p is 1 to 23, preferably 4 to 12).

[0046] Individual glucolipide molecules are abbreviated according to the following nomenclature: "GL-CXCY" means glucolipide of general formula (II), R 1b base and R 2b One of the bases is (CH2) p In CH3, p = X - 4, and the remaining R 1b Base or R 2b The base is (CH2) p In CH3, it is understood that p = Y - 4.

[0047] Therefore, the naming convention used does not distinguish between "CXCY" and "CYCX".

[0048] If one of the aforementioned indices X and / or Y has ":Z" appended to it, this means that each R 1b base and / or R 2b This means the group is an unbranched, unsubstituted hydrocarbon group having an X-3 or Y-3 carbon atom with a Z double bond.

[0049] In order to determine the content of glucolipid in the context of the present invention, only the mass of the glucolipid anion, for example, "general formula (I) minus one hydrogen," is considered. To determine the content of glucolipid in the context of the present invention, all glucolipid is converted to a protonated form (see general formula (II)) by acidification and quantified by HPLC.

[0050] A preferred composition according to the present invention comprises a glucolipide of general formula (II), wherein the composition contains at least 51 to preferably 98% by weight, preferably 60 to 95% by weight, more preferably 70 to 90% by weight, and particularly preferably 75 to 85% by weight of R 1b and R 2b It is characterized by containing the (CH2)6-CH3 glucolipide GL-C10C10 of general formula (II), where the weight percentage is based on the total of all existing glucolipides of general formula (II).

[0051] The mixed composition according to the present invention contains 1 to 30% by weight, preferably 5 to 25% by weight, and particularly preferably 10 to 20% by weight of GL-C8C10, where the weight percentage may be advantageous and therefore preferred when it is based on the total amount of all existing glucolipides of general formula (II).

[0052] A preferred composition according to the present invention is characterized by containing 0.5 to 20% by weight, preferably 3 to 17% by weight, and particularly preferably 5 to 15% by weight of GL-C10C12:1, where the weight percentage is based on the total of all existing glucolipides of general formula (II).

[0053] A more preferred composition according to the present invention is characterized in that the composition contains 0.5 to 20% by weight, preferably 2 to 15% by weight, and particularly preferably 3 to 12% by weight of GL-C10C12, where the weight percentage is based on the total of all present glucolipides of general formula (II).

[0054] A particularly preferred composition according to the present invention is characterized by comprising 1 to 30% by weight, preferably 5 to 25% by weight, particularly preferably 10 to 20% by weight of GL-C8C10; 0.5 to 20% by weight, preferably 3 to 17% by weight, particularly preferably 5 to 15% by weight of GL-C10C12:1; and 0.5 to 20% by weight, preferably 2 to 15% by weight, particularly preferably 3 to 12% by weight of GL-C10C12, where the weight percentages are based on the total of all glycolipids of general formula (II) present.

[0055] A particularly preferred composition according to the present invention is characterized in that the composition comprises 10-20% by weight of GL-C8C10, 5-15% by weight of GL-C10C12, and 3-12% by weight of GL-C10C12, where the weight percentages are based on the total of all existing glucolipides of general formula (II).

[0056] Sophorolipids can be used in their acidic or lactoneic forms according to the present invention. The term “acidic form” of sophorolipids is to be seen with respect to general formula (Ia) of EP2501813, and the term “lactone form” of sophorolipids is to be seen with respect to general formula (Ib) of EP2501813.

[0057] To determine the content of sophorolipids in acid or lactone form in the composition, refer to EP1411111B1, page 8, paragraph number

[0053] .

[0058] A preferred composition according to the present invention is characterized in that the pH of the composition at 25°C is 4.5 to 7.0, preferably 4.8 to 6.6, and particularly preferably 5.2 to 6.0.

[0059] A preferred composition according to the present invention is characterized by containing 40 to 70% by weight, preferably 45 to 55% by weight, of at least one glycolipid, where the weight percentage is based on the total composition.

[0060] These concentrated compositions according to the present invention have the advantage of improved stability during storage at low temperatures. These concentrated compositions according to the present invention exhibit improved odor. These concentrated compositions according to the present invention exhibit improved processability. Furthermore, the concentrated compositions according to the present invention have improved color stability over longer storage times.

[0061] A preferred composition according to the present invention is characterized by containing 0.2 to 12% by weight, preferably 0.4 to 8% by weight, of at least one glycolipid, where the weight percentage is based on the total composition.

[0062] These diluted compositions according to the present invention have the advantage of improved foam creaminess. These diluted compositions according to the present invention exhibit improved skin compatibility.

[0063] A preferred composition according to the present invention is characterized in that the composition contains at least one preservative selected from the group consisting of p-anisic acid, levulinic acid, lactic acid, and citric acid, preferably p-anisic acid, and salts of the aforementioned acids, in a concentration of preferably 0.01 to 14% by weight, preferably 0.02 to 11% by weight, where the weight percentage is based on the total composition.

[0064] The addition of these preservatives to the compositions according to the present invention has the advantage of improving solubilization performance in cosmetic oils. The addition of these preservatives to the compositions according to the present invention results in an improved taste. This finding makes them suitable for all oral care applications.

[0065] The present invention further relates to a method for producing a glycolipid formulation, preferably a cosmetic formulation or a pharmaceutical formulation, comprising the following steps: a) A step of providing a composition comprising 40-70% by weight, preferably 45-55% by weight, at least one glycolipid, 1.0-14% by weight, preferably 2.0-11% by weight, triethyl citrate, and water, wherein the weight percentages are characterized in that, based on the entire composition, the weight ratio of all glycolipids to all triethyl citrate contained in the composition is in the range of 5:1-20:1, preferably 6:1-15:1, and particularly preferably 7:1-12:1. b) Diluting the composition at least partially with water to obtain a formulation containing 0.2 to 20% by weight, preferably 0.4 to 15% by weight, of at least one glycolipid, where the weight percentage is based on the total formulation. The present invention provides the method including the above.

[0066] In the preferred method of the present invention, a preferred glycolipid of the composition according to the present invention is used.

[0067] A preferred method according to the present invention is characterized in that the pH of the formulation in step b) is adjusted to 4.5 to 7.0, preferably 4.8 to 6.6, and particularly preferably 5.2 to 6.0 at 25°C.

[0068] A preferred method according to the present invention is characterized in that the pH in step b) is adjusted by adding an organic or inorganic base, preferably in a concentrated form.

[0069] In the context of the present invention, the term “concentrated base” is understood to mean that the base is added in the form of a composition containing at least 60% by weight, and particularly at least 80% by weight, where the weight percentage is based on the total composition added.

[0070] In the method according to the present invention, it is preferable to use a base selected from the group comprising alkali metal and alkaline earth metal hydroxides such as NaOH, KOH, Mg(OH)2, Ca(OH)2, Al(OH)3, NH4OH, primary amines, secondary amines, tertiary amines, and quaternary amines.

[0071] Typical examples of suitable amines include 2-aminoethanol (ethanolamine, also known as MEA), diethanolamine (also known as DEA), 2,2',2''-nitrilotriethanol (triethanolamine, also known as TEA), 1-aminopropan-2-ol (also known as monoisopropanolamine), [(2-hydroxyethyl)trimethylammonium] (also known as choline), ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 1,4-diethylenediamine (also known as piperazine), aminoethylpiperazine, aminoethylethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide. Here, it is preferable to use 2-aminoethanol (ethanolamine, also known as MEA), diethanolamine (also known as DEA), 2,2',2''-nitrilotriethanol (triethanolamine, also known as TEA), 1-aminopropan-2-ol (also known as monoisopropanolamine), and (2-hydroxyethyl)trimethylammonium (also known as choline).

[0072] Particularly preferred bases are NaOH, KOH, NH3, NH4OH, and triethanolamine. According to the present invention, it is also possible to use a mixture of the above bases.

[0073] A preferred method according to the present invention is characterized by including, as step c), the addition of at least one additional component selected from the group consisting of emollients, emulsifiers, thickeners / viscosity modifiers / stabilizers, UV light protective filters, antioxidants, hydrotropes or polyols, solids and fillers, film-forming agents, pearlescent additives, deodorizing and antiperspirant active ingredients, insect repellents, self-tanning agents, preservatives, conditioning agents, fragrances, dyes, deodorants, cosmetic active ingredients, care additives, degreasing agents and solvents.

[0074] Substances that can be used as representative examples of individual groups are known to those skilled in the art and can be found, for example, in the German application DE102008001788.4. This patent application is incorporated for reference and therefore forms part of the disclosure.

[0075] For further optional ingredients and their amounts, the relevant handbook known to those skilled in the art is explicitly referenced, for example, K. Schrader, "Grundlagen und Rezepturen der Kosmetika [Cosmetics - fundamentals and formulations]," 2nd edition, pp. 329-341, Huethig Buch Verlag Heidelberg. The amount of individual additives is determined by the intended use. Typical boundary formulations for each application are known prior art and are included, for example, in the brochures of the manufacturers of the individual bases and active ingredients. These existing formulations can generally be adopted without modification. However, if necessary, modifications can be made with simple tests without complexity for adjustment and optimization.

[0076] The present invention further provides the use of triethyl citrate for stabilizing foam in aqueous compositions, preferably comprising rhamnolipid, glucolipid and sophorolipid, particularly rhamnolipid and glucolipid, and most particularly rhamnolipid, selected from the group of at least one glycolipid.

[0077] The present invention further provides the use of triethyl citrate to reverse the dependence of foam stability on pH in aqueous compositions preferably comprising rhamnolipid, glucolipid and sophorolipid, particularly rhamnolipid and glucolipid, and most particularly rhamnolipid, selected from the group of at least one glycolipid. [Brief explanation of the drawing]

[0078] [Figure 1] This shows the amount of foam over time for different rhamnolipid-containing compositions containing triethyl citrate, and different rhamnolipid-containing compositions without triethyl citrate. [Figure 2] This shows the amount of foam over time for different betaine-containing compositions containing triethyl citrate and different betaine-containing compositions without triethyl citrate. [Figure 3] This shows the solubilization of different essential oils by rhamnolipid in the presence and absence of triethyl citrate. [Figure 4] This shows the amount of foam over time for a sophorolipid-containing composition containing triethyl citrate and a sophorolipid-containing composition without triethyl citrate. [Figure 5] This shows the amount of foam over time for a glucolipid-containing composition containing triethyl citrate and a glucolipid-containing composition without triethyl citrate.

[0079] The present invention is described illustratively in the embodiments listed below, but is not intended to limit the present invention to the embodiments mentioned in the embodiments, and the scope of the present invention is determined by the entire specification and the claims. [Examples]

[0080] [Table 1]

[0081] Example 1: Evaluation of foaming properties using a SITA foam tester The foaming ability of surfactants and surfactant-based cleansing products is an important attribute recognized by consumers. Consumers associate rapid flash foaming and high foam volume with effectiveness and high quality. Both parameters can be measured using the SITA Foam Tester R-2000 measuring instrument from SITA Messtechnik. This instrument generates foam by introducing air into a specified amount of surfactant solution via a special rotor. The total volume of liquid and the resulting foam is measured over time using computer-controlled sensing technology.

[0082] Using this method, composition example A, which contains rhamnolipid and triethyl citrate, was evaluated for its foaming properties in comparison with a composition example containing only rhamnolipid.

[0083] Composition A (according to the present invention) was prepared as follows: 384 g of lyophilized, preservative-free rhamnolipid was dissolved in 374 g of water. The mixture was heated to 50°C with stirring, and 40 g of triethyl citrate (dermofeel® TEC eco) was added. The mixture was stirred for a further 30 minutes and then cooled to room temperature to obtain a very clear solution of composition A.

[0084] For the preparation of composition B (not according to the present invention), 96 g of lyophilized, preservative-free rhamnolipid was dissolved in 102 g of water. After stirring for a further 30 minutes, a very clear solution of composition B was obtained.

[0085] Using the same method, composition example C, containing sophorolipid and triethyl citrate, was evaluated for its foaming properties in comparison to composition example containing sophorolipid. 95 g of 40% aqueous solution of sophorolipid was mixed with 5 g of triethyl citrate. After stirring for 30 minutes and cooling to room temperature, a very clear solution of composition C was obtained. For the preparation of composition D, 95 g of 40% aqueous solution of sophorolipid was diluted by adding 5 g of water.

[0086] Glucolipide was obtained as described in WO2019 / 154970. 5 g of triethyl citrate was added to 95 g of a 50% aqueous solution of glucolipide. After stirring for 30 minutes and cooling to room temperature, a very clear solution of composition E was finally obtained. For the preparation of composition F, 95 g of a 50% aqueous solution of glucolipide was diluted by adding 5 g of water.

[0087] To evaluate the foaming performance, composition A and composition B were each diluted with water having a total hardness of 10°dH (German hardness) to a concentration of 0.5% by weight of the active surfactant substance.

[0088] Next, the dilutions of composition A and composition B were each divided into two 600 ml subbatches, and the pH values ​​of these subbatches were adjusted to pH 6.0 (A1, B1) and pH 7.0 (A2, B2) using an aqueous solution of 25 wt% sodium hydroxide. 300 ml of each test solution was tested for foaming at 30°C using a constant stirring speed of 1500 rpm for 10 seconds. Such measurement intervals were performed a total of eight times for each test solution. All samples were double-replicated. Figure 1 shows the amount of foam over time for each test solution.

[0089] Measurement parameters: Temperature: 30°C ± 0.5°C; Sample volume / measurement: 300 ml; Test sample concentration: 0.5 wt% in water (10°dH (= German hardness)), pH adjusted with NaOH; Stirring speed: 1500 rpm; Stirring time: 10 seconds; Number of intervals: 8; Number of repetitions: 2

[0090] As shown in Figure 1, composition (A) according to the present invention exhibits better overall performance in the SITA foam test compared to composition B, as indicated by faster flash foaming and higher foam volume. Surprisingly, the pH dependence is reversed for composition (A): composition B achieves best flash foaming and higher foam volume at pH 7.0 and its performance decreases as the pH decreases, while the foaming properties of composition (A) according to the present invention improve as the pH drops from 7.0 to 6.0. Excellent foaming at pH < 7.0 is a desirable characteristic for cosmetic cleansing ingredients and formulations, as cosmetic formulations are typically adjusted to pH < 7.0 to improve skin compatibility.

[0091] The results shown in Figure 2 are from the same procedure repeated using cocamidopropyl betaine instead of rhamnolipid. Here, no difference in foaming performance was observed regardless of pH.

[0092] To evaluate foaming performance, compositions C, D, E, and F were each diluted to a concentration of 0.5% by weight of the active surfactant substance in water with a total hardness of 10°dH (German hardness). For the dilution of compositions C and D, the pH values ​​of these sub-batches were adjusted to pH 6.0 (C1, D1) with a 25% by weight aqueous solution of sodium hydroxide and citric acid. 300 ml of each test solution was tested for foaming at 30°C using a constant stirring speed of 1500 rpm for 10 seconds. This measurement interval was performed a total of eight times for each test solution. All samples were double-replicated.

[0093] For dilution of compositions E and F, the pH values ​​of these sub-batches were adjusted to pH 5.0 (E1, F1) with a 25 wt% aqueous solution of sodium hydroxide and citric acid. 300 ml of each test solution was tested for foaming at 30°C using a constant stirring speed of 1500 rpm for 10 seconds. Such measurement intervals were performed a total of eight times for each test solution. All samples were double-replicated.

[0094] As shown in Figure 4, composition (C) according to the present invention exhibits better overall performance in the SITA foam test compared to composition D, as indicated by faster flash foaming and higher foam volume.

[0095] As shown in Figure 5, composition (E) according to the present invention exhibits better overall performance in the SITA foam test compared to composition F, as indicated by faster flash foaming and higher foam volume.

[0096] Example 2: Solubilization of essential oils The solubility of essential oils was investigated by mixing them with rhamnolipid or a mixture of rhamnolipid and triethyl citrate, followed by dilution with water. The minimum amount of solubilizer required to obtain a clear aqueous solution from 1% of the oil was determined. The test was designed by mixing 1g of oil with a defined amount of solubilizer (1g to 20g). Samples were visually inspected, stored for 24 hours, and re-evaluated. The results are shown in Figure 3.

[0097] In the case of composition (A) according to the present invention, the mixture of rhamnolipid (10 parts) and triethyl citrate (1 part) requires less solubilizer to solubilize rosemary oil and pink grapefruit flavor compared to composition (B) not according to the present invention and pure rhamnolipid.

Claims

1. At least one glycolipid in 0.2 to 70% by weight, 0.01 to 14% by weight of triethyl citrate, and a composition comprising water, wherein the weight percentage is based on the total composition. The weight ratio of all glycolipids to all triethyl citrate contained in the composition is in the range of 5:1 to 20:

1. A composition characterized in that its pH at 25°C is 4.5 to 6.

6.

2. The composition according to claim 1, characterized by comprising 40 to 70% by weight of at least one glycolipid, wherein the weight percentage is based on the total composition.

3. The composition according to claim 1, characterized by containing 0.2 to 12% by weight of at least one glycolipid, wherein the weight percentage is based on the total composition.

4. The composition according to any one of claims 1 to 3, characterized in that the composition contains 51 to 95% by weight of diRL-C10C10, where the weight percentage is based on the total amount of all rhamnolipids present.

5. The composition according to any one of claims 1 to 4, characterized in that the composition contains 0.5 to 9% by weight of monoRL-C10C10, where the weight percentage is based on the total amount of all rhamnolipids present.

6. The composition according to any one of claims 1 to 5, characterized in that the weight ratio of all existing diramnolipide to all existing monoramnolipide is greater than 51:

49.

7. The composition according to any one of claims 1 to 6, characterized in that the composition contains 0.5 to 25% by weight of diRL-C10C12, where the weight percentage is based on the total amount of all rhamnolipids present.

8. The composition according to any one of claims 1 to 7, characterized in that the composition comprises 0.1 to 5% by weight of monoRL-C10C12 and / or 0.1 to 5% by weight of monoRL-C10C12:1, wherein the weight percentage is based on the total of all rhamnolipids present.

9. The composition according to any one of claims 1 to 8, characterized in that the composition comprises 0.5 to 15% by weight of diRL-C10C12:1, 0.5 to 25% by weight of diRL-C10C12, 0.1 to 5% by weight of monoRL-C10C12, and 0.1 to 5% by weight of monoRL-C10C12:1, wherein the weight percentages are the sum based on all present rhamnolipids.

10. The composition according to any one of claims 1 to 9, characterized in that the composition comprises at least one preservative selected from the group consisting of p-anisic acid, levulinic acid, lactic acid, and citric acid, and salts of the aforementioned acids.

11. A method for producing a glycolipid formulation, comprising the following steps: a) At least one glycolipid in 40-70% by weight, 2.0 to 14% by weight of triethyl citrate, A step of providing a composition containing water, wherein the weight percentage is based on the entire composition, and the weight ratio of all glycolipids to all triethyl citrate contained in the composition is in the range of 5:1 to 20:

1. b) Diluting the composition at least partially with water to obtain a formulation containing 0.2 to 12% by weight of at least one glycolipid, wherein the weight percentage is based on the total formulation, A method characterized by adjusting the pH of the compound in step b) to a pH of 4.5 to 6.6 at 25°C.

12. Use of triethyl citrate to stabilize foam in an aqueous composition containing at least one glycolipid, wherein the weight ratio of all glycolipids to all triethyl citrate in the aqueous composition is in the range of 5:1 to 20:1, and the pH of the aqueous composition at 25°C is 4.5 to 6.

6.

13. Use of triethyl citrate to reverse the dependence of foam stability on pH in an aqueous composition containing at least one glycolipid, wherein the weight ratio of all glycolipids to all triethyl citrate in the aqueous composition is in the range of 5:1 to 20:1, and the pH of the aqueous composition at 25°C is 4.5 to 6.6.

Images