Antioxidant-free lutein powder and preparation method thereof

Abstract

The invention discloses xanthophyll powder without an antioxidant. The xanthophyll powder contains xanthophyll and a co-stabilizer. The xanthophyll powder of the present invention has excellent stability. The powder is well dissolved in water, and the saturated solution does not precipitate after being placed for a long time; in addition, xanthophyll can be effectively prevented from oxidative deterioration in air under the condition that an antioxidant does not need to be additionally added. In addition, the xanthophyll powder also has the advantage of simplicity and convenience in preparation, and is very suitable for industrial production.

Description

Technical Field

[0001] The present invention relates to lutein powder, in particular to lutein powder which does not contain an antioxidant and has excellent stability, and also relates to a preparation method thereof. Background Art

[0002] Lutein is a natural substance that protects eyesight, relieves visual fatigue, increases macular pigment density, and prevents macular degeneration and retinal pigment degeneration. It has been used in many fields such as food, cosmetics, and medicine. However, lutein has poor water solubility, resulting in low bioavailability. In addition, lutein's unique conjugated polyene structure makes its properties extremely unstable and easily degraded and loses its activity. These defects limit its application.

[0003] CN102038644A discloses a lutein water-soluble dry powder and a preparation method thereof. The dry powder includes lutein, as well as carrier materials such as polyvidone, polyethylene glycol, mannose, galactose, bile acid, and additives such as polysorbate, sorbitol fatty acid esters, fatty acid sucrose esters, tocopherol, ascorbic acid, and tert-butylhydroxyphenyl methyl ether. The preparation method includes: mixing lutein with at least two of the carrier materials and additives, adding an organic solvent, stirring and dissolving, evaporating to dryness under vacuum conditions at a temperature of 30 to 85°C, and crushing, and the entire preparation process is carried out under light-proof conditions. The dry powder has the advantages of good water solubility and good stability. However, antioxidants such as tocopherol need to be used in the powder and it needs to be prepared under light-proof conditions.

[0004] CN101433528A discloses a stable water-dispersible lutein microcapsule and a preparation method thereof. The microcapsule contains lutein, vegetable oil, and emulsifiers such as soybean lecithin, lecithin, Tween 80, sucrose ester or 1,2-propylene glycol, as well as capsule materials such as soluble starch, sodium carboxymethyl cellulose, ethyl cellulose and gelatin. The lutein is dissolved by an instantaneous high-temperature melting method, an emulsifier is added and emulsified by high-pressure homogenization, and the emulsion and the capsule material are subjected to fluidized bed granulation to obtain microcapsules. However, the microcapsule needs to use an emulsifier and high-pressure homogenization, which is not conducive to large-scale production.

[0005] Currently, there is still a need to provide better lutein products. Summary of the invention

[0006] The purpose of the present invention is to provide a water-soluble lutein powder with stable quality. The powder does not contain other additional ingredients such as antioxidants and emulsifiers, and can be prepared by a very simple industrial method. In order to achieve the purpose of the invention, the technical solution adopted by the present invention is:

[0007] A lutein powder contains lutein and a stabilizer, wherein the stabilizer consists of sodium starch octenylsuccinate and gamma-cyclodextrin in a weight ratio of 3:1 to 1:3.

[0008] In some preferred technical solutions, the weight ratio of sodium starch octenylsuccinate to γ-cyclodextrin in the stabilizer is 1:3, 1:2, 1:1, 2:1 or 3:1.

[0009] Lutein is very easy to be oxidized. In the prior art, antioxidants are often added to prevent it from deteriorating, and some encapsulation and isolation methods are used, but it is difficult to avoid a complicated preparation process. The present invention unexpectedly discovered that a combination of sodium starch octenyl succinate and γ-cyclodextrin in a specific ratio can well maintain the stability of lutein. This combination, as a co-stabilizer, can stabilize both low-content lutein and high-content lutein.

[0010] In some preferred technical solutions, the weight ratio of lutein to stabilizer in the powder is 1:9-1:1000.

[0011] In some preferred technical schemes, the weight ratio of lutein to stabilizer in the powder is 1:9, 1:10, 1:20, 1:40, 1:80, 1:100, 1:200, 1:300, 1:400, 1:500, 1:600, 1:700, 1:800, 1:900 or 1:1000.

[0012] In some preferred technical solutions, the weight percentage of lutein in the powder is 0.1%-10%.

[0013] In some preferred technical solutions, the weight percentage of lutein in the powder is 0.1%, 0.25%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 9.09% or 10%.

[0014] In some preferred technical solutions, the lutein powder of the present invention does not contain antioxidants except lutein, sodium starch octenylsuccinate and γ-cyclodextrin. Antioxidants are well known in the art, such as ascorbic acid, vitamin E, butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate, tert-butylhydroquinone, etc.

[0015] In some preferred technical solutions, the lutein powder of the present invention does not contain emulsifiers except lutein, sodium starch octenyl succinate and γ-cyclodextrin. Emulsifiers are well known in the art, such as Tween, Span, sodium lauryl sulfate, gelatin, phospholipids, etc.

[0016] The lutein powder of the present invention can be used as a raw material or intermediate to prepare food, medicine, functional beverage, etc. according to actual needs, and other ingredients can be added, for example, flavoring agents can be added to improve the taste.

[0017] In some preferred technical solutions, the lutein powder may optionally contain a flavoring agent.

[0018] These flavoring agents can be commonly used flavoring agents in the field of food or medicine, such as sucrose, maltose, etc. The weight percentage of the flavoring agent in the powder can be 0%-20%.

[0019] The present invention also provides a method for preparing the lutein powder:

[0020] A method for preparing lutein powder comprises the following steps:

[0021] (1) dissolving lutein in an organic solvent to obtain a solution a;

[0022] (2) dissolving sodium starch octenylsuccinate and γ-cyclodextrin, and an optional flavoring agent in water to obtain a solution b;

[0023] (3) Solution a and solution b are mixed evenly, and the mixed solution is spray-dried to obtain lutein powder.

[0024] In the method, the weight ratio of sodium starch octenylsuccinate to gamma-cyclodextrin is 3:1-1:3.

[0025] In the method, the organic solvent does not need to be particularly limited, as long as it can dissolve lutein, and can be ethanol, ethyl acetate, etc.

[0026] In the method, in the spray drying step (3), the organic solvent added in step (1) and the water added in step (2) can be removed.

[0027] The beneficial effects of the present invention are:

[0028] The lutein powder of the present invention has excellent solubility and stability. The powder dissolves well in water, and no precipitation occurs when the saturated solution is placed for a long time. In addition, the powder has excellent resistance to air oxidation, and can effectively prevent lutein from oxidizing and deteriorating in the air without the need for additional antioxidants. In addition, the preparation method of the lutein powder of the present invention is simple and can be obtained by conventional mixing, spray drying and the like, and is very suitable for industrial production. DETAILED DESCRIPTION

[0029] The present invention is further described below with examples, comparative examples and test examples. It should be understood that the contents of the specific implementation method are illustrative rather than restrictive, that is, they are not any limitations on the technical solutions of the present invention.

[0030] The raw and auxiliary materials in the examples are all commercially available.

[0031] Example 1

[0032] 0.1 kg of lutein was dissolved in 50 L of anhydrous ethanol to form a solution, 0.6 kg of sodium starch octenylsuccinate and 0.3 kg of γ-cyclodextrin were dissolved in 40 L of purified water to form an aqueous solution, the ethanol solution and the aqueous solution were mixed, and the mixed solution was spray-dried to obtain lutein powder.

[0033] Example 2

[0034] Referring to the method of Example 1, the amount of lutein used was 0.01 kg, the amount of sodium starch octenylsuccinate used was 1 kg, and the amount of γ-cyclodextrin used was 3 kg to prepare lutein powder.

[0035] Example 3

[0036] Referring to the method of Example 1, the amount of lutein used was 0.01 kg, the amount of sodium starch octenylsuccinate used was 7.5 kg, and the amount of γ-cyclodextrin used was 2.5 kg to prepare lutein powder.

[0037] Example 4

[0038] Referring to the method of Example 1, the amount of lutein used was 0.1 kg, the amount of sodium starch octenylsuccinate used was 0.5 kg, and the amount of γ-cyclodextrin used was 0.5 kg to prepare lutein powder.

[0039] Example 5

[0040] 0.1 kg of lutein was dissolved in 30 L of anhydrous ethanol to form a solution, 4 kg of sodium starch octenylsuccinate, 4 kg of γ-cyclodextrin, and 1.9 kg of maltose were dissolved in 50 L of purified water to form an aqueous solution, the ethanol solution and the aqueous solution were mixed, and the mixed solution was spray-dried to obtain lutein powder.

[0041] Comparative Example 1

[0042] The ratio of sodium starch octenyl succinate and γ-cyclodextrin was adjusted to prepare lutein powder. 0.1 kg of lutein was dissolved in 50 L of anhydrous ethanol to form a solution, 0.75 kg of sodium starch octenyl succinate and 0.15 kg of γ-cyclodextrin were dissolved in 40 L of purified water to form an aqueous solution, the ethanol solution and the aqueous solution were mixed, and the mixed solution was spray-dried to obtain lutein powder.

[0043] Comparative Example 2

[0044] The ratio of sodium starch octenyl succinate and γ-cyclodextrin was adjusted to prepare lutein powder. 0.1 kg of lutein was dissolved in 50 L of anhydrous ethanol to form a solution, 0.15 kg of sodium starch octenyl succinate and 0.75 kg of γ-cyclodextrin were dissolved in 40 L of purified water to form an aqueous solution, the ethanol solution and the aqueous solution were mixed, and the mixed solution was spray-dried to obtain lutein powder.

[0045] Comparative Example 3

[0046] Sodium octenyl succinate starch sodium was replaced with sodium carboxymethyl starch to prepare lutein powder. 0.1 kg of lutein was dissolved in 50 L of anhydrous ethanol to form a solution, 0.6 kg of sodium carboxymethyl starch and 0.3 kg of γ-cyclodextrin were dissolved in 40 L of purified water to form an aqueous solution, the ethanol solution and the aqueous solution were mixed, and the mixed solution was spray-dried to obtain lutein powder.

[0047] Comparative Example 4

[0048] Lutein powder was prepared by replacing γ-cyclodextrin with β-cyclodextrin. 0.1 kg of lutein was dissolved in 50 L of anhydrous ethanol to form a solution, 0.6 kg of sodium starch octenyl succinate and 0.3 kg of β-cyclodextrin were dissolved in 40 L of purified water to form an aqueous solution, the ethanol solution and the aqueous solution were mixed, and the mixed solution was spray-dried to obtain lutein powder.

[0049] Test Example 1 Solution Stability Test

[0050] 10 g of lutein powder obtained in Examples 1-5 and Comparative Examples 1-4 were added to 100 g of water and stirred in a 20°C water bath until the powder no longer dissolved to obtain a lutein saturated solution. The supernatant was placed at room temperature and its properties were observed after 0, 2, 4, 8, 24, and 48 hours. The results are shown in Table 1:

[0051] Table 1 Properties of saturated solutions of each group of samples after placement

[0052]

[0053]

[0054] It can be seen from comparative experiments that the lutein powder of the present invention has good solubility in water, and the saturated solution does not become turbid or precipitate after being placed for a long time, indicating good stability.

[0055] In Comparative Examples 3 and 4, the stabilizer was replaced with sodium carboxymethyl starch or β-cyclodextrin, and a trace amount of precipitation appeared in the solution after 24 hours or 48 hours, indicating poor stability. This phenomenon shows that different types of starch derivatives and different types of cyclodextrin have a significant effect on the stability of lutein saturated solution, and the type of stabilizer is crucial to maintaining the stability of lutein solution.

[0056] Test Example 2 Antioxidant Stability Test

[0057] The lutein powders prepared in Examples 1-5 and Comparative Examples 1-4 were respectively exposed to air at room temperature, and samples were taken at 0, 6, and 12 hours after exposure to determine the lutein content in the powders (ultraviolet-visible spectrophotometry, wavelength 445 nm), and the percentage of content decrease was calculated (the difference between the 12-hour content and the 0-hour content divided by the 0-hour content). The results are shown in Table 2.

[0058] Table 2 Changes in lutein content of each group of samples after exposure to air

[0059] 0 hours 6 hours 12 hours Content change percentage Example 1 9.990％ 9.973％ 9.951％ -0.390％ Example 2 0.246％ 0.244％ 0.244％ -0.813％ Example 3 0.100％ 0.099％ 0.099％ -1.000％ Example 4 9.082％ 9.060％ 9.040％ -0.462％ Example 5 0.997％ 0.994％ 0.992％ -0.502％ Comparative Example 1 9.990％ 9.782％ 9.402％ -5.886％ Comparative Example 2 9.992％ 9.681％ 9.583％ -4.093％ Comparative Example 3 9.998％ 9.390％ 9.110％ -8.882％ Comparative Example 4 9.996％ 9.403％ 9.281％ -7.153％

[0060] The results show that after being exposed to the air for 12 hours, the lutein content in the samples of Comparative Examples 1 and 2 decreased by more than 4%, and the lutein content in the samples of Comparative Examples 3 and 4 decreased by more than 7%, indicating that a large amount of lutein was oxidized and deteriorated.

[0061] The content of lutein in the lutein powder of the present invention varies very little, remaining at 1% or less, and has significantly better stability. This phenomenon indicates that the specific ratio combination of sodium octenyl succinate starch and γ-cyclodextrin of the present invention has a good protective effect on lutein.

[0062] The present invention has been described in detail above using general descriptions and specific implementation methods. On this basis, those skilled in the art may make some changes or improvements thereto. These changes or improvements made without departing from the present invention are all within the content required to be protected by the present invention.

Claims

1. A lutein powder, comprising lutein and a stabilizer, wherein the stabilizer is composed of sodium starch octenylsuccinate and γ-cyclodextrin in a weight ratio of 3:1-1:

3.

2. The lutein powder according to claim 1, wherein the weight ratio of lutein to the stabilizer is 1:9-1:1000.

3. The lutein powder according to claim 1, wherein the weight percentage of lutein in the powder is 0.1%-10%.

4. The lutein powder according to claim 1, further optionally containing a flavoring agent.

5. The lutein powder according to claim 1, wherein the flavoring agent is selected from sucrose or maltose.

6. The lutein powder according to claim 1, wherein the lutein powder contains no antioxidant except lutein, sodium starch octenylsuccinate and γ-cyclodextrin.

7. The lutein powder according to claim 1, wherein the lutein powder contains no emulsifier except lutein, sodium starch octenylsuccinate and γ-cyclodextrin.

8. The method for preparing the lutein powder according to any one of claims 1 to 7, comprising the following steps: (1) dissolving lutein in an organic solvent to obtain a solution a; (2) dissolving sodium starch octenyl succinate, γ-cyclodextrin, and an optional flavoring agent in water to obtain a solution b; (3) mixing the solution a and the solution b evenly, and spray drying the mixture to obtain lutein powder.

9. The preparation method according to claim 8, wherein the weight ratio of sodium starch octenyl succinate to γ-cyclodextrin in step (2) is 3:1-1:

3.

10. The preparation method according to claim 8, wherein the organic solvent is selected from ethanol and ethyl acetate.

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