Preparation method of natural plant pigment composition and application of natural plant pigment composition in food

Abstract

The invention belongs to the technical field of food additives, and particularly relates to a preparation method of a natural plant pigment composition and application of the natural plant pigment composition in food. The preparation method comprises the following steps: S1, dissolving a natural plant pigment in water to obtain a natural plant pigment solution, adjusting the pH value of the natural plant pigment solution to 7-8, then adding cyclodextrin, uniformly stirring, continuously stirring, and standing after stirring to obtain a solution I; s2, sequentially adding spirulina peptidoglycan and polyamino acid into the obtained solution I, uniformly mixing, stirring, adding halide salt after stirring, continuously stirring, standing after stirring, centrifuging, mixing an obtained solid product with edible auxiliary materials, and freeze-drying to obtain the natural plant pigment composition. The raw materials used in the invention are food-grade, safe and harmless, and can be used in food dyeing and coloring, endow food and beverage products with saturated and uniform colors, and improve the brilliance of food.

Description

Technical Field

[0001] The invention belongs to the technical field of food additives, and in particular relates to a preparation method of a natural plant pigment composition and application of the composition in food. Background Art

[0002] Natural pigments mainly include three categories: natural plant pigments, natural animal pigments and natural mineral pigments. Natural plant pigments are the most widely used, involving various industries such as food, textiles, cosmetics, medicine, leather industry, printing and dyeing. Natural plant pigments refer to the pigment components existing in the roots, stems, leaves, flowers, fruits and barks of plants, such as turmeric, sappan wood, indigo, safflower, black beans, green walnut skins, etc. Their green and environmentally friendly characteristics have become the focus of the current development of new pigments and dyes. Compared with synthetic pigments, natural plant pigments have many advantages. Because they are derived from plants, they have the advantages of high safety, no toxic side effects and natural color tones. They also have certain physiological functions and medicinal values, such as preventing neurological and cardiovascular diseases, protecting the liver from oxidative damage, etc., and can be used as good health products and condiments in daily life.

[0003] Food is the most basic material guarantee for human survival. The development of green food is a need for people's environmental awareness, health awareness and living standards to continue to improve. Colorants play an important role in improving the appearance and quality of food. Compared with synthetic pigments, green and healthy natural plant pigments have become a hot spot for market development and application in the health industry. By adding natural pigments to food, since the pigments themselves have certain physiological functions, they will not only increase the nutritional value of the food, but also improve the sensory properties of the food such as color, aroma and taste. However, natural plant pigments have poor stability and are easily reacted to light, temperature, oxygen and heavy metals. In addition, natural plant pigments have poor tinting power, which can easily cause uneven dyeing. Summary of the invention

[0004] The primary purpose of the present invention is to provide a method for preparing a natural plant pigment composition and application thereof in food, so as to enable the wide application of natural plant pigments in food.

[0005] To this end, the present invention provides the following technical solutions.

[0006] One aspect of the present invention provides a method for preparing a natural plant pigment composition, the preparation method comprising the following steps:

[0007] S1: dissolving a natural plant pigment in water to obtain a natural plant pigment solution with a mass concentration of 1-5%, adjusting the pH of the natural plant pigment solution to 7-8 with a sodium bicarbonate solution with a concentration of 40-80wt%, then adding cyclodextrin and stirring evenly, then placing in a 30-40°C water bath and stirring continuously at a speed of 200-600rpm for 1-4h, and standing for 20-40min after the stirring to obtain a solution I;

[0008] S2: Add spirulina peptidoglycan and polyamino acid to the obtained solution I in sequence according to the volume mass ratio of 100 mL: 0.1-0.5 mg: 1-5 g and mix evenly, then stir at 40-60° C. for 1-2 h, add halide salt after stirring and continue stirring for 30-60 min, let stand for 30-60 min after stirring, then centrifuge at 5000-10000 rpm for 5-10 min, mix the obtained solid product with edible auxiliary materials in a mass ratio of 1:0.2-0.6, and freeze-dry at -30--20° C. to obtain a natural plant pigment composition.

[0009] In a preferred embodiment of the present invention, the natural plant pigments include anthocyanins, chlorophyll, betacyanin, betacyanin, lithospermum red, gardenia yellow, anthocyanins, capsanthin, safflower yellow, sodium copper chlorophyllin, and curcumin.

[0010] In a preferred embodiment of the present invention, the cyclodextrin is selected from any one of α-cyclodextrin, β-cyclodextrin or γ-cyclodextrin.

[0011] In a preferred embodiment of the present invention, the added amount of the cyclodextrin is 20-30% of the mass of the natural plant pigment.

[0012] In a preferred embodiment of the present invention, the polyamino acid is γ-polyglutamic acid and / or polyaspartic acid.

[0013] In a preferred embodiment of the present invention, the halide salt is selected from one or a mixture of two or more of ferrous chloride, ferric chloride, calcium chloride, magnesium chloride, sodium chloride and potassium iodide.

[0014] In a preferred embodiment of the present invention, the amount of the halogenated salt added is 0.1-0.5% of the mass of the polyamino acid.

[0015] In a preferred embodiment of the present invention, the edible auxiliary material is selected from any one of carboxymethyl cellulose, sodium carboxymethyl cellulose, sodium alginate, chitosan, calcium alginate, arabinoxylan, microcrystalline cellulose, whey protein, soy protein isolate, and modified starch, or a mixture of two or more thereof.

[0016] Another aspect of the present invention also provides an application of the natural plant pigment composition prepared according to the preparation method as described above in food.

[0017] In a preferred embodiment of the present invention, the amount of the natural plant pigment composition added to the food is 1 to 5 wt%.

[0018] By means of the above technical solution, the present invention has at least the following advantages:

[0019] 1. The present invention aims at the problem that natural plant pigments have low stability and poor tinting power. By combining natural plant pigments with a certain amount of protective agent, the natural plant pigment molecules can be protected on the one hand, and the stability of natural plant pigments can be improved on the other hand, so that natural plant pigments have higher stability and improve their tinting power. The raw materials used in the present invention are all food grade, safe and harmless, can be used in food dyeing and coloring, give saturated and uniform colors to food and beverage products, and improve the vividness of food.

[0020] 2, the present invention utilizes the peculiar structure of cyclodextrin to wrap, protect natural plant pigment molecule by using cyclodextrin in alkaline environment, obtain the natural plant pigment of cyclodextrin wrap.Alkaline environment can guarantee the structural stability of cyclodextrin, promotes the coating of cyclodextrin to pigment molecule, guarantees the stability of the natural plant pigment of cyclodextrin wrap.Add spirulina peptidoglycan and polyamino acid subsequently, spirulina peptidoglycan can provide antioxidant property, avoid the influence of oxygen and heavy metal in the external environment on pigment molecule, add polyamino acid under the existence of halogenated salt, can cause the natural plant pigment of polymerized dextrin wrap to gather on the polyamino acid molecular chain, and gradually precipitate out in the adding process of halogenated salt, finally precipitate is combined with edible auxiliary material and namely obtain the natural plant pigment composition.

[0021] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail as follows. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Unless otherwise specified, the percentage content involved in the present invention refers to mass percentage for solid-liquid mixing and solid-solid mixing, and refers to volume percentage for liquid-liquid mixing.

[0024] Unless otherwise specified, the percentage concentrations referred to in the present invention all refer to final concentrations, which refer to the percentage of the added component in the system after the addition of the component.

[0025] The temperature parameters in the present invention, if not specifically limited, allow for both constant temperature treatment and treatment within a certain temperature range. The constant temperature treatment allows the temperature to fluctuate within the precision range controlled by the instrument.

[0026] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods.

[0027] Unless otherwise specified, the materials and reagents used in the following examples are all food grade and commercially available, wherein γ-polyglutamic acid (purity>99%) was purchased from Zhejiang Yicun Biotechnology Co., Ltd.

[0028] Embodiment 1:

[0029] S1: anthocyanidin is dissolved in water to obtain an anthocyanidin solution with a mass concentration of 3%, and a sodium bicarbonate solution with a concentration of 40-80wt% is used to adjust the pH of the anthocyanidin solution to 8, and then β-cyclodextrin (the amount added is 25% of the mass of anthocyanidin) is added and stirred evenly, and then placed in a 35°C water bath and stirred at a speed of 400 rpm for 2.5 hours. After the stirring is completed, it is allowed to stand for 30 minutes to obtain a solution I.

[0030] S2: Add Spirulina peptidoglycan and γ-polyglutamic acid to the obtained solution I in a volume mass ratio of 100 mL: 0.3 mg: 3 g in sequence and mix evenly, then stir at 50°C for 1.5 h, add a mixture of ferrous chloride and ferric chloride in a mass ratio of 1:2 after stirring (the added amount is 0.3% of the mass of γ-polyglutamic acid) and continue stirring for 45 min, let it stand for 45 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with carboxymethyl cellulose in a mass ratio of 1:0.4, and freeze-dry at -30°C to obtain an anthocyanin composition.

[0031] Embodiment 2:

[0032] S1: Betalain was dissolved in water to obtain a betalain solution with a mass concentration of 5%, and the pH of the betalain solution was adjusted to 8 with a sodium bicarbonate solution with a concentration of 80wt%, and then β-cyclodextrin (the amount added was 30% of the mass of betalain) was added and stirred evenly, and then placed in a 30°C water bath and stirred at a speed of 600 rpm for 1 hour. After the stirring was completed, it was allowed to stand for 40 minutes to obtain a solution I.

[0033] S2: Add spirulina peptidoglycan and γ-polyglutamic acid to the obtained solution I in a volume mass ratio of 100 mL: 0.1 mg: 1 g in sequence and mix evenly, then stir at 40°C for 2 h, add a mixture of calcium chloride and ferric chloride in a mass ratio of 1:3 after stirring (the added amount is 0.1% of the mass of γ-polyglutamic acid) and continue stirring for 60 min, let it stand for 30 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with chitosan in a mass ratio of 1:0.6, and freeze-dry at -30°C to obtain a betalain composition.

[0034] Embodiment 3:

[0035] S1: Dissolve shikonin in water to obtain a shikonin solution with a mass concentration of 1%, adjust the pH of the shikonin solution to 8 with a 40wt% sodium bicarbonate solution, then add β-cyclodextrin (the added amount is 20% of the mass of shikonin) and stir evenly, then place in a 40°C water bath and stir continuously at 200rpm for 4h, and let stand for 20min after stirring to obtain solution I.

[0036] S2: Add spirulina peptidoglycan and γ-polyglutamic acid to the obtained solution I in a volume mass ratio of 100 mL: 0.5 mg: 5 g in sequence and mix evenly, then stir at 60°C for 1 h, add a mixture of ferrous chloride and calcium chloride in a mass ratio of 1:1 after stirring (the added amount is 0.5% of the mass of γ-polyglutamic acid) and continue stirring for 30 min, let stand for 60 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with microcrystalline cellulose in a mass ratio of 1:0.2, and freeze-dry at -30°C to obtain a shikonin composition.

[0037] Embodiment 4:

[0038] S1: Wheat starch was dispersed in a citric acid solution with a mass concentration of 5% according to a mass volume ratio of 10 g:100 mL to obtain a starch suspension. Manganese chloride (the amount added was 3% of the mass of the starch) was added to the obtained starch suspension, and heated and stirred until the starch suspension became a translucent viscous colloidal solution, and then sodium trimetaphosphate (the amount added was 0.5% of the mass of the starch) was added and continued to stir for 2 hours. After the stirring was completed, it was allowed to stand for 30 minutes, and then filtered. The obtained precipitate was dried and crushed to obtain modified starch.

[0039] S2: anthocyanidin is dissolved in water to obtain an anthocyanidin solution with a mass concentration of 3%, and a sodium bicarbonate solution with a concentration of 40-80wt% is used to adjust the pH of the anthocyanidin solution to 8, and then β-cyclodextrin is added (the amount added is 25% of the mass of anthocyanidin) and stirred evenly, and then placed in a 35°C water bath and stirred at a speed of 400 rpm for 2.5 hours. After the stirring is completed, it is allowed to stand for 30 minutes to obtain a solution I.

[0040] S3: Add spirulina peptidoglycan and γ-polyglutamic acid to the obtained solution I in a volume mass ratio of 100 mL: 0.3 mg: 3 g in sequence and mix evenly, then stir at 50°C for 1.5 h, add a mixture of ferrous chloride and ferric chloride in a mass ratio of 1:2 after stirring (the added amount is 0.3% of the mass of γ-polyglutamic acid) and continue stirring for 45 min, let it stand for 45 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with modified starch in a mass ratio of 1:0.4, and freeze-dry at -30°C to obtain an anthocyanin composition.

[0041] Comparative Example 1: No cyclodextrin was added to anthocyanidins in step 1

[0042] S1: dissolving anthocyanin in water to obtain an anthocyanin solution with a mass concentration of 3%, which is referred to as solution I.

[0043] S2: Add Spirulina peptidoglycan and γ-polyglutamic acid to the obtained solution I in a volume mass ratio of 100 mL: 0.3 mg: 3 g in sequence and mix evenly, then stir at 50°C for 1.5 h, add a mixture of ferrous chloride and ferric chloride in a mass ratio of 1:2 after stirring (the added amount is 0.3% of the mass of γ-polyglutamic acid) and continue stirring for 45 min, let it stand for 45 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with carboxymethyl cellulose in a mass ratio of 1:0.4, and freeze-dry at -30°C to obtain an anthocyanin composition.

[0044] Comparative Example 2: No peptidoglycan was added in step 2

[0045] S1: anthocyanidin is dissolved in water to obtain an anthocyanidin solution with a mass concentration of 3%, and a sodium bicarbonate solution with a concentration of 40-80wt% is used to adjust the pH of the anthocyanidin solution to 8, and then β-cyclodextrin (the amount added is 25% of the mass of anthocyanidin) is added and stirred evenly, and then placed in a 35°C water bath and stirred at a speed of 400 rpm for 2.5 hours. After the stirring is completed, it is allowed to stand for 30 minutes to obtain a solution I.

[0046] S2: The γ-polyglutamic acid in the obtained solution I was mixed in sequence in a volume mass ratio of 100 mL: 3 g, and then stirred at 50°C for 1.5 h. After stirring, a mixture of ferrous chloride and ferric chloride in a mass ratio of 1:2 was added (the added amount was 0.3% of the mass of γ-polyglutamic acid) and continued to stir for 45 min. After stirring, it was allowed to stand for 45 min, and then centrifuged at 10000 rpm for 5 min. The obtained solid product was mixed with carboxymethyl cellulose in a mass ratio of 1:0.4 and freeze-dried at -30°C to obtain an anthocyanin composition.

[0047] Comparative Example 3: No amino acid was added in step 2

[0048] S1: anthocyanidin is dissolved in water to obtain an anthocyanidin solution with a mass concentration of 3%, and a sodium bicarbonate solution with a concentration of 40-80wt% is used to adjust the pH of the anthocyanidin solution to 8, and then β-cyclodextrin (the amount added is 25% of the mass of anthocyanidin) is added and stirred evenly, and then placed in a 35°C water bath and stirred at a speed of 400 rpm for 2.5 hours. After the stirring is completed, it is allowed to stand for 30 minutes to obtain a solution I.

[0049] S2: Add Spirulina peptidoglycan to the obtained solution I in a volume mass ratio of 100 mL: 0.3 mg and mix evenly, then stir at 50°C for 1.5 h, add a mixture of ferrous chloride and ferric chloride in a mass ratio of 1:2 after stirring (the added amount is 0.3% of the mass of γ-polyglutamic acid) and continue stirring for 45 min, let it stand for 45 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with carboxymethyl cellulose in a mass ratio of 1:0.4, and freeze-dry at -30°C to obtain an anthocyanin composition.

[0050] Comparative Example 4: No halide salt was added in step 2

[0051] S1: anthocyanidin is dissolved in water to obtain an anthocyanidin solution with a mass concentration of 3%, and a sodium bicarbonate solution with a concentration of 40-80wt% is used to adjust the pH of the anthocyanidin solution to 8, and then β-cyclodextrin (the amount added is 25% of the mass of anthocyanidin) is added and stirred evenly, and then placed in a 35°C water bath and stirred at a speed of 400 rpm for 2.5 hours. After the stirring is completed, it is allowed to stand for 30 minutes to obtain a solution I.

[0052] S2: Add Spirulina peptidoglycan and γ-polyglutamic acid to the obtained solution I in sequence according to the volume mass ratio of 100 mL: 0.3 mg: 3 g and mix evenly, then stir at 50°C for 1.5 h, let stand for 45 min after stirring, then centrifuge at 10000 rpm for 5 min, mix the obtained solid product with carboxymethyl cellulose in a mass ratio of 1:0.4, and freeze-dry at -30°C to obtain an anthocyanin composition.

[0053] Comparative Example 5: No three were added in step 2

[0054] S1: anthocyanidin is dissolved in water to obtain an anthocyanidin solution with a mass concentration of 3%, and a sodium bicarbonate solution with a concentration of 40-80wt% is used to adjust the pH of the anthocyanidin solution to 8, and then β-cyclodextrin (the amount added is 25% of the mass of anthocyanidin) is added and stirred evenly, and then placed in a 35°C water bath and stirred at a speed of 400 rpm for 2.5 hours. After the stirring is completed, it is allowed to stand for 30 minutes to obtain a solution I.

[0055] S2: Carboxymethyl cellulose is added to the obtained solution I (the amount added is the same as in Example 1), mixed, and then freeze-dried at -30°C to obtain an anthocyanin composition.

[0056] Test example: Stability test of different pigment compositions

[0057] Test objects: pigment compositions / pigments of Examples 1-4 and Comparative Examples 1-5;

[0058] Test method: A spectrophotometer was used to measure the absorbance A0 of the pigment composition (the detection wavelength of anthocyanin was 500 nm, the detection wavelength of betacyanin was 535 nm, and the detection wavelength of shikonin was 516 nm) and the absorbance A of the pigment composition after storage at light-proof / room temperature (25°C), 3000 l ux light / room temperature (25°C), and 3000 l ux light / 35°C for 0 days, 10 days, 20 days, 30 days, 60 days, 90 days, 120 days, 150 days, and 180 days, respectively, wherein the pigment retention rate (%) = A / A0*100.

[0059] Experimental results: See Table 1.

[0060] Table 1 Pigment retention rate of each group

[0061]

[0062]

[0063]

[0064]

[0065] It can be seen from the results in Table 1 that, compared with the pigment compositions of Comparative Examples 1 to 5, the pigment compositions of Examples 1 to 4 of the present invention have better stability and show more excellent stability under both light and high temperature.

[0066] Test 2: Application of different compositions in beverages

[0067] The pigment compositions of Example 1, Example 4 and Comparative Examples 1-5 of the present invention were added to commercially available Sprite beverages at an amount of 3 g of the pigment composition per 100 mL of commercially available Sprite beverages, respectively. The beverages were placed at room temperature and the color changes of the beverages were observed every day until the color of the beverages faded visibly to the naked eye, and the time required from the beginning to the fading was recorded. The results are shown in Table 2.

[0068] Table 2 Fading time of each group of beverages

[0069] Group Fading time (days) Example 1 272 Example 4 295 Comparative Example 1 176 Comparative Example 2 259 Comparative Example 3 247 Comparative Example 4 261 Comparative Example 5 195

[0070] It can be seen from the results in Table 2 that, compared with Comparative Examples 1-5, the color change time of the pigment-containing beverages in Examples 1 and 4 of the present invention is significantly higher.

[0071] Experiment 3: Application of different compositions in food noodles

[0072] 5g of the pigment composition of Example 1, Example 4 and Comparative Examples 1-5 were taken respectively, dissolved with an appropriate amount of water, added to 500g of flour to neutralize the noodles and make noodles, and the noodles were boiled in water for 10 minutes, and the color change of the noodles was observed. Among them, the noodles containing the pigment compositions of Examples 1 and 4 had no obvious color change after being boiled for 10 minutes, and the noodles containing the compositions of Comparative Examples 1-5 all faded to a certain extent after being boiled for 10 minutes. The above results show that the pigment composition of the present invention has the advantages of good stability and strong coloring ability.

[0073] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a natural plant pigment composition, characterized in that: The preparation method comprises the following steps: S1: dissolving a natural plant pigment in water to obtain a natural plant pigment solution with a mass concentration of 1-5%, adjusting the pH of the natural plant pigment solution to 7-8 with a sodium bicarbonate solution with a concentration of 40-80wt%, then adding cyclodextrin and stirring evenly, then placing in a 30-40°C water bath and stirring continuously at a speed of 200-600rpm for 1-4h, and standing for 20-40min after the stirring to obtain a solution I; S2: Add spirulina peptidoglycan and polyamino acid to the obtained solution I in sequence according to the volume mass ratio of 100 mL: 0.1-0.5 mg: 1-5 g and mix evenly, then stir at 40-60° C. for 1-2 h, add halide salt after stirring and continue stirring for 30-60 min, let stand for 30-60 min after stirring, then centrifuge at 5000-10000 rpm for 5-10 min, mix the obtained solid product with edible auxiliary materials in a mass ratio of 1:0.2-0.6, and freeze-dry at -30--20° C. to obtain a natural plant pigment composition.

2. The method for preparing the natural plant pigment composition according to claim 1, wherein The natural plant pigments include anthocyanidin, chlorophyll, betacyanin, betacyanin, lithospermum red, gardenia yellow, anthocyanins, capsanthin, safflower yellow, sodium copper chlorophyllin, and curcumin.

3. The preparation method of the natural plant pigment composition according to claim 1, characterized in that, The cyclodextrin is selected from any one of α-cyclodextrin, β-cyclodextrin or γ-cyclodextrin.

4. The method for preparing the natural plant pigment composition according to claim 1, wherein The added amount of the cyclodextrin is 20-30% of the mass of the natural plant pigment.

5. The method for preparing the natural plant pigment composition according to claim 1, wherein The polyamino acid is γ-polyglutamic acid and / or polyaspartic acid.

6. The method for preparing the natural plant pigment composition according to claim 1, wherein The halide salt is selected from one or a mixture of two or more of ferrous chloride, ferric chloride, calcium chloride, magnesium chloride, sodium chloride and potassium iodide.

7. The method for preparing the natural plant pigment composition according to claim 1, characterized in that: The added amount of the halogenated salt is 0.1-0.5% of the mass of the polyamino acid.

8. The method for preparing the natural plant pigment composition according to claim 1, wherein The edible auxiliary material is selected from any one of carboxymethyl cellulose, sodium carboxymethyl cellulose, sodium alginate, chitosan, calcium alginate, arabinoxylan, microcrystalline cellulose, whey protein, soy protein isolate, and modified starch, or a mixture of two or more thereof.

9. Use of the natural plant pigment composition prepared by the preparation method according to any one of claims 1 to 8 in food.

10. The use according to claim 9, characterized in that: The added amount of the natural plant pigment composition in the food is 1-5wt%.

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