Diluted solution containing carotenoids and method for producing the same

Abstract

To provide diluted solution containing carotenoids, which can stably store carotenoids for a long term, and a method for producing diluted solution.SOLUTION: Carotenoid-containing diluted solution contains carotenoids and antioxidant. In the carotenoid-containing diluted solution, the content of carotenoids is 0.02 to 0.04 mass% based on the total amount of carotenoid-containing diluted solution, and the content of antioxidant is 0.2 to 0.5 mass% based on the total amount of carotenoid-containing diluted solution, thereby solving the above problem.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a carotenoid-containing dilute solution and a method for producing the same. [Background technology]

[0002] In recent years, in response to the growing health consciousness of consumers, there has been active development of foods and beverages containing various nutrients and foods and beverages using naturally derived ingredients. Among these, development is also underway for beverages containing vitamin A, which has the effect of suppressing the activity of active oxygen, and its precursor, β-carotene.

[0003] Carotenoids, such as β-carotene, have a drawback in that their resistance to oxygen, heat, and the like, especially light, is extremely low due to the long conjugated system in their molecules. Therefore, colorants and foods containing carotenoid pigments are prone to fading over time, particularly due to the influence of light. Once colorants and foods have faded, there is a risk that the carotenoids have been lost, making it impossible to efficiently ingest them.

[0004] For this reason, various attempts have been proposed to prevent the fading of carotenoid pigments. For example, it has been proposed to prevent the loss of β-carotene by adding vitamin C, vitamin B2, and vitamin E to a beverage containing β-carotene (Patent Document 1), and to add a water-soluble flavonol glycoside and a water-soluble antioxidant to an aqueous liquid containing a carotenoid pigment (Patent Document 2). However, in these patent documents, the storage stability of β-carotene was evaluated for a maximum of only four weeks, which is not considered to be sufficient storage stability from the perspective of product distribution and storage. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-106843 [Patent Document 2] Japanese Patent Application Publication No. 2-135070 Summary of the Invention [Problem to be solved by the invention]

[0006] These previous attempts to prevent the fading of carotenoid pigments have not been carried out for a long period of time longer than one month, and the storage stability of carotenoids in all cases has been insufficient from the viewpoints of product distribution and storage. Therefore, a solution that can stably store carotenoids for a long period of time has been desired. Furthermore, in the process of applying a carotenoid-containing solution to a wide range of product forms, for example, in the production process of beverages such as juices and sports drinks, and processed foods containing water, the carotenoid-containing dilution may be exposed to acidic conditions. Therefore, there has been a demand for a dilution that can stably preserve carotenoids for a long period of time even under acidic conditions. In view of the above, an object of the present invention is to provide a carotenoid-containing dilution that allows carotenoids to be stably stored for a long period of time, and a method for producing the same. [Means for solving the problem]

[0007] The present invention relates to the following. [1] A carotenoid-containing dilution containing carotenoids and an antioxidant, wherein the content of the carotenoids is 0.02 to 0.04% by mass relative to the total amount of the carotenoid-containing dilution, and the content of the antioxidant is 0.2 to 0.5% by mass relative to the total amount of the carotenoid-containing dilution. [2] The carotenoid-containing dilution solution according to [1], wherein the carotenoid is β-carotene. [3] The carotenoid-containing dilution according to [1] or [2], wherein the antioxidant is ascorbic acid or an ascorbic acid derivative, or a salt thereof. [4] The carotenoid-containing dilution according to any one of [1] to [3], wherein the antioxidant is ascorbic acid and / or sodium ascorbate. [5] A method for producing a carotenoid-containing dilution, comprising the step of adding an antioxidant to a water dilution containing carotenoids, wherein the content of the carotenoids is 0.02 to 0.04 mass% relative to the total amount of the carotenoid-containing dilution, and the amount of the antioxidant added is 0.2 to 0.5 mass% relative to the total amount of the carotenoid-containing dilution. [6] The method for producing a carotenoid-containing dilution according to [5], wherein the carotenoid is β-carotene. [7] The method for producing a carotenoid-containing diluted solution according to [5] or [6], wherein the antioxidant is ascorbic acid, an ascorbic acid derivative, or a salt thereof. [8] The method for producing a carotenoid-containing diluted solution according to any one of [5] to [7], wherein the antioxidant is ascorbic acid and / or sodium ascorbate. [Effects of the Invention]

[0008] According to the present invention, there are provided a carotenoid-containing dilution that allows carotenoids to be stably stored for a long period of time, and a method for producing the same. DETAILED DESCRIPTION OF THE INVENTION

[0009] (Carotenoid-containing diluted solution) The present invention relates to a carotenoid-containing dilution containing carotenoids and an antioxidant, wherein the carotenoid content is 0.02 to 0.04 mass% relative to the total amount of the carotenoid-containing dilution (hereinafter also simply referred to as "dilution"), and the antioxidant content is 0.2 to 0.5 mass% relative to the total amount of the dilution.

[0010] This carotenoid-containing dilution liquid has the above-mentioned constitution and therefore exhibits excellent storage stability for a long period of time.

[0011] The method for preparing the carotenoid-containing diluted solution is not particularly limited, but it can be obtained by diluting a carotenoid-containing emulsion with water and adding an antioxidant. Alternatively, the carotenoid-containing diluted solution can be obtained by adding an antioxidant to a carotenoid-containing emulsion described below and diluting the mixture.

[0012] (Carotenoid-containing emulsion) The carotenoid-containing emulsion is not particularly limited as long as it is a solution containing carotenoids, but may contain carotenoids, medium-chain fatty acids (MCTs), polyglycerol fatty acid esters, lecithin, lipophilic emulsifiers, tocopherols, and water.

[0013] The components contained in the carotenoid-containing emulsion and the carotenoid-containing dilution will be described below.

[0014] (Carotenoids) Carotenoids are yellow to red terpenoid pigments, and examples thereof include those derived from plants, algae, and bacteria. Furthermore, carotenoids are not limited to those derived from natural sources, and may be any carotenoids obtained by conventional methods.

[0015] Specific examples of carotenoids include lycopene, α-carotene, β-carotene, γ-carotene, δ-carotene, actinioerythrol, bixin, canthaxanthin, capsorubin, β-8'-apo-carotenal (apocarotenal), β-12'-apo-carotenal, xanthophylls (e.g., astaxanthin, fucoxanthin, lutein, zeaxanthin, capsanthin, β-cryptoxanthin, violaxanthin, etc.), fucoxanthin, and hydroxyl or carboxyl derivatives thereof, with β-carotene being particularly preferred. These may be used alone or in combination of two or more.

[0016] The content of β-carotene in the carotenoid-containing emulsion (hereinafter also simply referred to as "emulsion") is preferably 1 to 50% by mass, more preferably 1 to 20% by mass, and even more preferably 1 to 5% by mass, based on the total amount of the emulsion. The content of β-carotene in the carotenoid-containing dilution is preferably 0.02 to 0.04% by mass, more preferably 0.02 to 0.03% by mass, based on the total amount of the dilution.

[0017] The carotenoids may be present alone, or may constitute carotenoids together with oil used in extracting them from natural products.

[0018] The carotenoids may be crystalline or amorphous. When the carotenoids are crystalline, it is preferred that at least 90% by mass of the carotenoids are present in the carotenoid-containing composition in an amorphous state.

[0019] When the carotenoids are crystalline carotenoids, the crystalline carotenoids are present in an amorphous state in the composition, so that the effects that may be impaired due to the presence of crystals are not impaired, and the absorbability of the carotenoid components in the body can be increased.

[0020] The amorphous nature of crystalline carotenoids can be confirmed using known means for detecting crystalline structure. Furthermore, the presence of crystalline carotenoids can be confirmed by conventional methods, such as differential scanning calorimetry (DSC), polarized light microscopy, and X-ray diffraction. The absence of detectable crystalline forms using these known techniques indicates that the carotenoid is amorphous. It is particularly preferable to confirm the amorphous nature of a carotenoid based on the presence of a DSC endothermic peak. Specifically, a DSC Q2000 (TA Instruments Japan, Inc.) is used to determine the endothermic and exothermic temperatures of an emulsion (lyophilized to remove water) or a powder composition (in powder form) in a temperature range of 30°C to 200°C, with one heating-cooling cycle (15°C / min). The absence of a discernible endothermic peak indicates the carotenoid is amorphous.

[0021] Furthermore, when the carotenoids are crystalline carotenoids, it is sufficient that at least 90 to 100% by mass of the crystalline carotenoid is amorphous, and in terms of dynamic absorption, it is preferable that 95 to 100% by mass is amorphous. For example, whether at least 90% by mass of the crystalline carotenoid contained in the carotenoids is amorphous can be confirmed by comparing the endothermic heat of the endothermic peak derived from carotenoid crystals in the carotenoid-containing composition of the present invention measured by differential scanning calorimetry (DSC) with the endothermic heat of the endothermic peak of a carotenoid crystal preparation.

[0022] Here, "crystalline carotenoid" does not refer to a specific carotenoid, but rather refers to carotenoids that, when in the form of a carotenoid-containing oil or paste, can exist as crystals at any temperature in the temperature range of -5°C to 35°C due to various factors such as the production method, processing, and storage. In particular, among the carotenoids mentioned above, lycopene, β-carotene, δ-carotene, zeaxanthin, lutein, astaxanthin, fucoxanthin, and the like are carotenoids that are likely to exist as crystals.

[0023] (antioxidant) The carotenoid-containing emulsion and carotenoid-containing dilution contain, as an antioxidant, at least one selected from the group consisting of ascorbic acid, derivatives thereof, and salts thereof.

[0024] Ascorbic acid may be any of L-, D-, and DL-isomers, but the L-isomer is preferred from the viewpoint of availability and the like.

[0025] Ascorbic acid salts, ascorbic acid derivatives, and salts thereof, ascorbic acid and sodium ascorbate are preferred.Other ascorbic acid salts, ascorbic acid derivatives, and salts thereof include sodium L-ascorbate, potassium L-ascorbate, calcium L-ascorbate, L-ascorbic acid phosphate, magnesium salt of L-ascorbic acid phosphate, L-ascorbic acid sulfate, disodium L-ascorbic acid sulfate, L-ascorbic acid stearate, L-ascorbic acid 2-glucoside, L-ascorbic acid palmitate, L-ascorbyl tetraisopalmitate, etc.; and fatty acid esters of ascorbic acid such as L-ascorbyl stearate, L-ascorbyl tetraisopalmitate, and L-ascorbyl palmitate.In addition, commercially available products may be used as ascorbic acid salts, ascorbic acid derivatives, and salts thereof, as appropriate.

[0026] The content of the antioxidant in the carotenoid-containing dilution is preferably 0.2 to 0.5 mass %, more preferably 0.2 to 0.4 mass %, and even more preferably 0.2 mass % or more and less than 0.4 mass %, based on the total amount of the dilution.

[0027] (Polyglycerol fatty acid ester) The polyglycerol fatty acid ester is an ester of polyglycerol having an average degree of polymerization of 2 or more, preferably 2 to 10, and a fatty acid having 8 to 18 carbon atoms (for example, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, or linoleic acid). The number of fatty acids added to polyglycerol is a minimum of 1 and a maximum of 2 plus the degree of polymerization of polyglycerol.

[0028] Preferred examples of polyglycerol fatty acid esters include hexaglycerol monooleate, hexaglycerol monostearate, hexaglycerol monopalmitate, hexaglycerol monomyristate, hexaglycerol monolaurate, decaglycerol monooleate, decaglycerol monostearate, decaglycerol monopalmitate, decaglycerol monomyristate, and decaglycerol monolaurate. Any one of these may be used alone, or two or more may be used in combination. Decaglycerol monostearate and decaglycerol monooleate are particularly preferred.

[0029] Any polyglycerol fatty acid ester can be used as long as it is suitable for food use, but preferably has an HLB of 10 to 16, more preferably 11 to 16, even more preferably 11 to 15, and most preferably 12 to 15. Here, HLB indicates the hydrophilic-hydrophobic balance used in the field of surfactants, and for example, the following calculation formula (Kawakami formula) can be used. HLB = 7 + 11.7 log(MW / MO) Here, MW is the molecular weight of the hydrophilic group, and MO is the molecular weight of the hydrophobic group. Alternatively, the HLB value listed in a catalog or the like may be used.

[0030] The content of polyglycerol fatty acid ester in the carotenoid-containing emulsion is not particularly limited as long as it does not affect the properties, but is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and even more preferably 3 to 15% by mass, based on the total amount of the emulsion. The content of polyglycerol fatty acid ester in the carotenoid-containing dilution is not particularly limited as long as it does not affect the properties, but is preferably 0.01 to 0.3 mass %, more preferably 0.02 to 0.2 mass %, and even more preferably 0.03 to 0.15 mass % relative to the total amount of the dilution.

[0031] (lecithin) The lecithin is not particularly limited as long as it is naturally derived, and specific examples include plant lecithins such as soybean lecithin and rapeseed lecithin, egg yolk lecithin, fractionated lecithin, high-purity lecithin, enzymatically decomposed lecithin, and enzyme-treated lecithin. The fractionated lecithin referred to here is obtained by fractionating specific components from plant lecithin or egg yolk lecithin using an organic solvent such as ethanol, taking advantage of differences in solubility. The enzymatically decomposed lecithin is obtained by subjecting plant lecithin, egg yolk lecithin, fractionated lecithin, or the like to hydrolysis, transfer reaction, or the like with a phospholipase. Various enzymatically decomposed lecithins can be obtained depending on the type of lecithin and the type of phospholipase used. In this specification, these are collectively referred to as enzymatically decomposed lecithin, and any type of enzymatically decomposed lecithin may be used. Among these, soybean lecithin, egg yolk lecithin, high-purity lecithin, and enzymatically decomposed lecithin are preferred, with enzymatically decomposed lecithin being particularly preferred. The above-mentioned lecithins may be used alone or in combination of two or more.

[0032] The content of lecithin in a carotenoid-containing emulsion is not particularly limited as long as it does not affect the properties, but is preferably 0.1 to 30% by mass, more preferably 0.5 to 20% by mass, and even more preferably 1 to 15% by mass, relative to the total amount of the emulsion. The content of lecithin in the carotenoid-containing dilution is not particularly limited as long as it does not affect the properties, but is preferably 0.001 to 3 mass%, more preferably 0.005 to 2 mass%, and even more preferably 0.01 to 1 mass%, relative to the total amount of the dilution.

[0033] (lipophilic emulsifier) The lipophilic emulsifier is not particularly limited as long as it is suitable for food use, and various types may be used. The HLB value is preferably 4 to 5. For example, glycerin fatty acid esters can be used. It is possible.

[0034] The content of glycerin fatty acid ester in a carotenoid-containing emulsion is not particularly limited as long as it does not affect the properties, but is preferably 0.01 to 5 mass %, more preferably 0.03 to 3 mass %, and even more preferably 0.05 to 5 mass % of the total amount of the emulsion. The content of glycerin fatty acid ester in the carotenoid-containing dilution is not particularly limited as long as it does not affect the properties, but it is preferably 1.0 × 10 -4 ~5.0×10 -2 mass%, more preferably 3.0 × 10 -4 ~3.0×10 -2 % by mass, and even more preferably 5.0×10 -4 ~1.0×10 -2 It is expressed in mass%.

[0035] (glycerin) The glycerin content in the carotenoid-containing emulsion is not particularly limited as long as it does not affect the properties, but is preferably 5 to 70% by mass, more preferably 10 to 60% by mass, and even more preferably 20 to 55% by mass, relative to the total amount of the emulsion. The glycerin content in the carotenoid-containing diluted solution is not particularly limited as long as it does not affect the properties, but is preferably 0.05 to 1 mass %, more preferably 0.1 to 0.8 mass %, and even more preferably 0.2 to 0.6 mass % relative to the total amount of the diluted solution.

[0036] (Tocopherols) Examples of tocopherols include dl-α-tocopherol, dl-β-tocopherol, dl-γ-tocopherol, dl-δ-tocopherol, dl-α-tocopherol acetate, dl-α-tocopherol nicotinate, dl-α-tocopherol linoleate, and dl-α-tocopherol succinate. Among these, dl-α-tocopherol, dl-β-tocopherol, dl-γ-tocopherol, dl-δ-tocopherol, and mixtures thereof (mixed tocopherols) are more preferred, with mixed tocopherols being even more preferred. Furthermore, carboxylic acid esters of these, especially acetate esters, are preferably used as tocopherol derivatives. The group of compounds consisting of tocotrienol and its derivatives includes α-tocotrienol, β-tocotrienol, γ-tocotrienol, δ-tocotrienol, etc. Furthermore, as tocotrienol derivatives, carboxylic acid esters of these compounds, particularly acetate esters, are preferably used.

[0037] The content of tocopherols in the carotenoid-containing dilution is not particularly limited as long as it does not affect the properties. However, it is preferably 1.0×10 -4 ~5.0×10 -2 mass%, more preferably 5.0 × 10 -4 ~3.0×10 -2 % by mass, and even more preferably 1.0×10 -3 ~1.0×10 -2 It is expressed in mass%.

[0038] (water) Various types of water can be used without any particular limitation. For example, tap water or deionized water can be used. From the viewpoints of economy and ease of use, it is preferable to use tap water. From the viewpoint of stability of the carotenoid-containing emulsion and the carotenoid-containing dilution, it is preferable to use deionized water.

[0039] (others) For the carotenoid-containing emulsion and carotenoid-containing diluent, ethanol and known additive materials can be used depending on the intended use and form, as long as they do not impair the effects of the invention. Examples of known additives include known excipients, flavors, colorants, emulsifiers, stabilizers, thickeners, enzymes, preservatives, antibacterial agents, lubricants, surfactants, disintegrants, disintegration inhibitors, binders, absorption promoters, adsorbents, humectants, solubilizers, preservatives, flavors, sweeteners, and UV absorbers. These additives can be blended as needed within a range that does not impair the effects described above. There are no particular limitations on the amount of these additives, as long as they are within the range of common use.

[0040] (container) The carotenoid-containing emulsion and the carotenoid-containing dilution may be in any form. A suitable form of the carotenoid-containing emulsion and the carotenoid-containing dilution is, for example, that they are filled in a light-shielding container. By blocking light, deterioration and discoloration of the carotenoids over time can be prevented.

[0041] (Application) Carotenoid-containing emulsions and dilutions containing carotenoids can be used as cosmetics, quasi-drugs, medical supplies, hygiene products, pharmaceuticals, foods and beverages, supplements, etc. Carotenoids are expected to have antioxidant and other effects.

[0042] (food and drink) When a carotenoid-containing emulsion or a carotenoid-containing dilution is used as a food ingredient, it can be used not only as a general food, but also as a food for specified health uses, a health supplement, a nutritional supplement, a functional food, a food for the sick, a food additive, etc. Examples of the form of food or drink that may contain this aqueous solution include soft drinks, juice, milk, pudding, jelly, candy, gum, gummy candy, yogurt, chocolate, soup, cookies, snacks, ice cream, popsicles, bread, cake, cream puffs, ham, meat sauce, curry, stew, cheese, butter, dressing, etc.

[0043] Carotenoid-containing emulsions and carotenoid-containing diluents can be used with water, protein, carbohydrates, lipids, vitamins, minerals, organic acids, organic bases, fruit juice, flavors, and the like as their main ingredients. Examples of proteins include animal and vegetable proteins such as whole milk powder, skim milk powder, partially skim milk powder, casein, soy protein, egg protein, and meat protein, as well as their hydrolysates and butter. Examples of carbohydrates include sugars, modified starch (dextrin, soluble starch, British starch, oxidized starch, starch esters, starch ethers, and the like), and dietary fiber. Examples of lipids include vegetable oils and fats such as lard, safflower oil, corn oil, rapeseed oil, palm oil, fractionated oils thereof, hydrogenated oils, and interesterified oils. Examples of vitamins include vitamin A, carotenes, B vitamins, vitamin C, D vitamins, vitamin E, K vitamins, vitamin P, vitamin Q, niacin, nicotinic acid, pantothenic acid, biotin, inositol, choline, and folic acid. Examples of minerals include calcium, potassium, magnesium, sodium, copper, iron, manganese, zinc, selenium, and whey minerals. Examples of organic acids include malic acid, citric acid, lactic acid, and tartaric acid. Two or more of these ingredients may be used in combination, and synthetic products and / or foods and beverages containing large amounts of these may also be used.

[0044] When carotenoid-containing emulsions and carotenoid-containing dilutions are used as ingredients in foods and beverages, they can be produced according to conventional methods. The amount, method, and timing of incorporation into foods and beverages can be appropriately selected. Furthermore, they can be packaged in appropriate containers such as bottles, bags, cans, boxes, and packs, as needed.

[0045] (Method of producing a dilute solution containing carotenoids) The method for producing a dilute solution containing carotenoids includes a step of adding an antioxidant to a dilute aqueous solution containing carotenoids.

[0046] (Machines used in manufacturing) The machinery used to produce the carotenoid-containing emulsion and carotenoid-containing dilution is not particularly limited, and machines such as mixers, agitators, dispersers, homomixers, homogenizers, high-pressure homogenizers, ultra-high-pressure homogenizers, ball mills, colloid mills, planetary mills, wet OB mills, rotary grinders, kneaders, kneaders, spray dryers, vacuum dryers, freeze dryers, and vibrating sieves can be used alone or in combination. [Example]

[0047] The present invention will be described in more detail based on the following examples. However, the scope of the present invention is not limited by these examples. Formulation Examples 1-2, 1-3, 2-2, and 2-3 correspond to Examples, and Formulation Examples 1-1, 2-1, and 2-4 correspond to Comparative Examples.

[0048] (Preparation of 3% β-carotene emulsion) A container was charged with 11 g of carotenoid MCT suspension (manufactured by BASF, trade name "BASF NBC 30%"), 17.6 g of MCT (manufactured by Kao Corporation, trade name "Coconard MT"), 7.5 g of decaglycerin monostearate (manufactured by Nikko Chemicals Co., Ltd., trade name "Decaglyn 1-50SV"), and 10 g of decaglycerin monooleate (manufactured by Taiyo Kagaku Co., Ltd., trade name "Sunsoft"). A mixture of 2.5 g of β-carotene-containing lecithin (provided by Mitsubishi Corporation Life Sciences Co., Ltd., trade name "Elmizer A"), 2 g of enzyme-degraded lecithin (provided by Mitsubishi Corporation Life Sciences Co., Ltd., trade name "Elmizer A"), 0.14 g of glycerin fatty acid ester (provided by Sakamoto Pharmaceutical Industry Co., Ltd., trade name "THL-15"), 48.76 g of glycerin fatty acid ester (provided by Sakamoto Pharmaceutical Industry Co., Ltd., trade name "Glycerin"), 0.5 g of a mixed tocopherol preparation (provided by Mitsubishi Corporation Life Sciences Co., Ltd., trade name "Emix 50L"), and 10 g of deionized water was added and stirred to obtain a 3% β-carotene emulsion.

[0049] (Sample preparation) (Formulation example 1-1: No antioxidants added, neutral) The 3% β-carotene emulsion was diluted 100 times with deionized water to adjust the β-carotene content to 0.03 mass % (30 mg / 100 mL) relative to the total amount of the diluted solution, thereby obtaining a neutral diluted solution. (Formulation example 1-2: 0.3% by mass of ascorbic acid added, neutral) The same procedure as in Formulation Example 1-1 was carried out, and ascorbic acid (provided by DSM K.K., trade name "L-ascorbic acid") was added to the obtained neutral dilution in an amount of 0.3 mass % based on the total amount of the neutral dilution. (Formulation example 1-3: 0.3% by mass of sodium ascorbate added, neutral) The same procedure as in Formulation Example 1-1 was carried out, and sodium ascorbate (manufactured by Fuso Chemical Co., Ltd., trade name "Sodium L-ascorbate") was added to the obtained neutral dilution in an amount of 0.3 mass % based on the total amount of the neutral dilution.

[0050] (Formulation example 2-1: No antioxidants added, acidic) 15.55 g of citric acid (manufactured by Fuso Chemical Co., Ltd., trade name "Fuso Citrate (Anhydrous) L") and 4.64 g of sodium citrate (manufactured by Jiali Bio Group (Qingdao) Limited, trade name "Citrate Na") were added to 1,000 g of deionized water and stirred to obtain a citrate buffer solution with a pH of 3. The 3% β-carotene emulsion was diluted 100-fold with the citrate buffer solution to adjust the β-carotene content to 0.03 mass% (30 mg / 100 mL) relative to the total volume of the diluted solution, thereby obtaining an acidic diluted solution. (Formulation example 2-2: 0.3% by mass of ascorbic acid added, acidic) The same procedure as in Formulation Example 2-1 was carried out, and ascorbic acid was added to the obtained diluted acid solution in an amount of 0.3% by mass relative to the total amount of the diluted acid solution. (Formulation example 2-3: 0.3% by mass sodium ascorbate added, acidic) The same procedure as in Formulation Example 2-1 was carried out, and sodium ascorbate was added to the obtained diluted acid solution in an amount of 0.3% by mass based on the total amount of the diluted acid solution. (Formulation example 2-4: 0.6% by mass of sodium ascorbate added, acidic) The same procedure as in Formulation Example 2-1 was carried out, and sodium ascorbate was added to the obtained diluted acid solution in an amount of 0.6% by mass based on the total amount of the diluted acid solution.

[0051] (β-carotene stability evaluation) Formulation Examples 1-1 to 1-3 and Formulation Examples 2-1 to 2-4 were stored in a thermostatic chamber at 40°C for 3 months in the dark, and the residual β-carotene rate (%) in the solution for each formulation was calculated and evaluated by the method described below immediately after storage, after 1 month, after 2 months, and after 3 months. Formulations with a residual β-carotene rate of 80% or more after 3 months were evaluated as "◯" (good storage stability), and those with a residual β-carotene rate of less than 80% or 120% or more were evaluated as "×" (poor storage stability).

[0052] (Measurement of β-carotene concentration) Each formulation example was stored at 40°C for a specified period, protected from light, and then returned to room temperature. 1 mL was taken with a whole pipette and diluted to a volume of 50 mL with acetone (first-class pure, manufactured by Junsei Chemical Co., Ltd.). The absorbance at the maximum absorption wavelength (436 nm) of the resulting solution was measured using a spectrophotometer (Japan Spectroscopic Corporation, ultraviolet-visible spectrophotometer, model number: V-630). This was multiplied by the extinction coefficient of 1960 to calculate the concentration of β-carotene. (Calculation of residual rate of β-carotene) For each formulation example, the ratio of the β-carotene concentration after storage at 40°C for 1 month, 2 months, and 3 months to the β-carotene concentration immediately after storage at 40°C was calculated as a percentage (%).

[0053] The results for the neutral diluted solution and the acid diluted solution are shown in Tables 1 and 2, respectively. The figures in parentheses in the tables are the residual rate (%) of β-carotene.

[0054] [Table 1]

[0055] As shown in Table 1, Formulation Examples 1-2 and 1-3 are formulations in which 0.3% by mass of ascorbic acid or sodium ascorbate is added to a β-carotene-containing neutral dilution solution, and the residual rate of β-carotene in the neutral dilution solution stored in the dark at 40°C for 3 months was 80% or more, indicating excellent storage stability of β-carotene. On the other hand, in Formulation Example 1-1, neither ascorbic acid nor sodium ascorbate was added, and the residual rate of β-carotene in the neutral diluted solution after one month of storage at 40°C in the dark was less than 80%, indicating poor storage stability of β-carotene.

[0056] [Table 2]

[0057] As shown in Table 2, Formulation Examples 2-2 and 2-3 are formulations in which 0.3% by mass of ascorbic acid or sodium ascorbate is added to a β-carotene-containing acidic diluted solution. After storing the acidic diluted solution at 40°C in the dark for 3 months, the residual rate of β-carotene in the solution was 80% or more, demonstrating excellent storage stability of β-carotene. On the other hand, in Formulation Example 2-1, neither ascorbic acid nor sodium ascorbate was added, and after storage at 40°C in the dark for 2 months, the residual rate of β-carotene in the diluted acidic solution was less than 80%, indicating poor storage stability of β-carotene. In addition, Formulation Example 2-4 is a formulation containing 0.6% by mass of sodium ascorbate, and the residual rate of β-carotene in the diluted solution stored at 40°C for 1 to 3 months in the dark was 120% or more. This was the result of adding 0.6% by mass of sodium ascorbate to the acidic diluted solution and storing it. This is thought to be because the emulsion was broken, causing uneven sampling during measurement, resulting in a large amount of β-carotene being collected.

[0058] From the above, it was found that when an antioxidant is added to a carotenoid-containing diluted solution containing 0.02 to 0.04 mass% of carotenoids relative to the total amount of the diluted solution at 0.2 to 0.5 mass% relative to the total amount of the diluted solution, the residual rate of carotenoids in the diluted solution stored in the dark at 40°C for 3 months is 80% or more, indicating excellent storage stability. [Industrial Applicability]

[0059] According to the present invention, a carotenoid-containing dilution solution having excellent long-term storage stability of carotenoids can be used to provide beverages, foods, etc. Since the present invention provides excellent long-term storage stability of carotenoids not only under neutral conditions but also under acidic conditions, carotenoids, particularly β-carotene, can be effectively added and blended in beverages such as juices and sports drinks, and processed foods containing water.

Claims

1. A carotenoid-containing dilution solution containing carotenoids and an antioxidant, The content of the carotenoids is 0.02 to 0.04% by mass based on the total amount of the carotenoid-containing dilution solution, The carotenoid-containing diluted solution has a content of the antioxidant of 0.2 to 0.5% by mass relative to the total amount of the carotenoid-containing diluted solution.

2. 2. The carotenoid-containing dilution according to claim 1, wherein the carotenoid is β-carotene.

3. 3. The carotenoid-containing dilution according to claim 1, wherein the antioxidant is ascorbic acid, an ascorbic acid derivative, or a salt thereof.

4. 3. The carotenoid-containing dilution according to claim 1, wherein the antioxidant is ascorbic acid and / or sodium ascorbate.

5. A method for producing a carotenoid-containing diluted solution, comprising a step of diluting a carotenoid-containing emulsion with water and adding an antioxidant, The content of the carotenoids is 0.02 to 0.04% by mass based on the total amount of the carotenoid-containing dilution solution, The method for producing the carotenoid-containing diluted solution, wherein the amount of the antioxidant added is 0.2 to 0.5% by mass based on the total amount of the carotenoid-containing diluted solution.

6. 6. The method for producing a carotenoid-containing dilute solution according to claim 5, wherein the carotenoid is β-carotene.

7. 7. The method for producing a carotenoid-containing diluted solution according to claim 5, wherein the antioxidant is ascorbic acid, an ascorbic acid derivative, or a salt thereof.

8. 7. The method for producing a carotenoid-containing diluted solution according to claim 5, wherein the antioxidant is ascorbic acid and / or sodium ascorbate.

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