阅读说明：本技术 一种可长时间稳定存放的二氢杨梅素复合物溶液的制备方法 (Preparation method of dihydromyricetin compound solution capable of being stably stored for long time ) 是由 陈晓霞 冯玉红 吴伟都 成官哲 沈珊珊 杨扬 李言郡 欧凯 于 2020-12-30 设计创作，主要内容包括：本发明公开了一种可长时间稳定存放的二氢杨梅素复合物溶液的制备方法,属于功能性食品或食品原料的生产工艺技术领域,首先用乙醇溶解和提取原料中的二氢杨梅素,然后加入谷物醇溶蛋白制成有机相,将有机相缓慢加入酪蛋白酸钠溶液中形成二氢杨梅素-蛋白复合物溶液,蒸发法除去乙醇,再加入阴离子多糖溶液并调节溶液pH至酸性,制得二氢杨梅素-蛋白-多糖复合物溶液。复合物溶液中的粒径为100～600nm,分散性指数≤0.3,Zeta-电位-10～-40mV,具有良好的理化稳定性,二氢杨梅素包封率高于60%,二氢杨梅素载量超过5mg/mL并抑制其在贮藏过程中的析出。(The invention discloses a preparation method of a dihydromyricetin compound solution capable of being stably stored for a long time, belonging to the technical field of production processes of functional foods or food raw materials. The particle size of the compound solution is 100-600 nm, the dispersibility index is less than or equal to 0.3, the Zeta-potential is minus 10-minus 40mV, the compound solution has good physicochemical stability, the encapsulation rate of the dihydromyricetin is higher than 60%, the loading capacity of the dihydromyricetin exceeds 5mg/mL, and the precipitation of the dihydromyricetin in the storage process is inhibited.)

1. A method for preparing a dihydromyricetin compound solution capable of being stably stored for a long time is characterized by comprising the following steps:

(1) diluting the ethanol solution of dihydromyricetin with water, adding gliadin, and stirring to obtain organic phase;

(2) slowly adding the organic phase into the sodium caseinate solution to form a dihydromyricetin-protein complex solution, and evaporating ethanol to obtain a dihydromyricetin-protein complex solution;

(3) mixing the dioxymyricetin-protein complex with the anionic polysaccharide solution, and adjusting the pH value to be acidic to obtain a dihydromyricetin-protein-polysaccharide complex solution;

(4) homogenizing the dihydromyricetin-protein-polysaccharide complex solution under high pressure, and sterilizing to obtain the dihydromyricetin complex solution.

2. A method for preparing a dihydromyricetin complex solution capable of being stored stably for a long period of time according to claim 1, wherein the ethanol solution of dihydromyricetin is obtained by extracting dihydromyricetin from Ampelopsis grossedentata raw material with ethanol, and removing insoluble precipitate; the concentration of the dihydromyricetin is 30-50 mg/mL.

3. A method for preparing a dihydromyricetin complex solution capable of being stored stably for a long period of time as claimed in claim 2, wherein the Ampelopsis grossedentata raw material comprises at least one of Ampelopsis grossedentata, Ampelopsis grossedentata powder, Ampelopsis grossedentata extract, Ampelopsis grossedentata flavone or Ampelopsis grossedentata product rich in dihydromyricetin.

4. A method according to claim 2, wherein the prolamines include, but are not limited to, zein, rice prolamine, hordein, and triticale prolamine.

5. The method for preparing a dihydromyricetin complex solution capable of being stored stably for a long time according to claim 1, wherein the ethanol volume concentration of the dihydromyricetin ethanol solution diluted by water in the step (1) is 70-85%; the mass concentration of the cereal prolamin is 1-5%.

6. The method for preparing a dihydromyricetin complex solution capable of being stored stably for a long time according to claim 1, wherein the mass concentration of the sodium caseinate solution used in the step (2) is 1% -8%; the mass ratio of the sodium caseinate to the cereal prolamin is 1: 1-2: 1.

7. A method for preparing a dihydromyricetin complex solution capable of being stored stably for a long time according to claim 1, wherein the anionic polysaccharide used in the step (3) is one or more of sodium carboxymethylcellulose, pectin and soybean polysaccharide, or a complex colloid containing one or more of sodium carboxymethylcellulose, pectin and soybean polysaccharide; the mass ratio of the anionic polysaccharide to the sodium caseinate is 2: 3-1: 1.

8. A method for preparing a dihydromyricetin complex solution capable of being stored stably for a long time according to claim 1, wherein the pH value is adjusted by using an edible acidity regulator in the step (3);

and (4) adjusting the pH value in the step (3) to be 3.5-4.5 at the end point.

9. A method for producing a dihydromyricetin complex solution that can be stored stably for a long period of time as claimed in claim 1, wherein the high-pressure homogenization is a two-stage high-pressure homogenization at a pressure of 200/50 MPa.

Technical Field

The invention relates to the technical field of production processes of functional foods or functional food raw materials, in particular to a preparation method of a dihydromyricetin compound solution capable of being stably stored for a long time.

Background

Dihydromyricetin is a flavonoid polyphenol with a plurality of physiological and pharmacological activities, the actions of the flavonoid polyphenol comprise antioxidation, anticancer, anti-inflammatory, antimicrobial, liver protection, lipid and glucose metabolism regulation, and the dihydromyricetin also has the actions of relieving alcoholism and protecting nerves, and ampelopsis grossedentata, hovenia dulcis thunb, grapes and berries are natural sources of the dihydromyricetin, wherein the content of the dihydromyricetin in the ampelopsis grossedentata is rich (more than 10 percent). Although the dihydromyricetin can be dissolved in hot water, the solubility is very low at low temperature or room temperature, and the functional beverage rich in the dihydromyricetin is easy to separate out and generate insoluble precipitate in the shelf life, which not only causes the deterioration of the appearance of the product, but also greatly influences the effective content of the dihydromyricetin. Therefore, the improvement of the solubility of the dihydromyricetin at low temperature or room temperature, in particular the long-term storage stability of the beverage containing the dihydromyricetin, so as to improve the shelf life of the functional beverage is a problem which needs to be solved for expanding the application of the dihydromyricetin in the field of functional foods.

Chinese patent 20151000453.8, entitled "Dihydromyricetin Cyclodextrin clathrate and its preparation method", uses cyclodextrin to coat Dihydromyricetin, thereby improving the water solubility of Dihydromyricetin. Although the scheme can improve the solubility of the dihydromyricetin in water, the functional beverage is still easy to separate out in the shelf life after the coating product is added into the functional beverage.

Disclosure of Invention

Aiming at the problems that precipitates are easy to separate out and not high in long-term stability of functional beverages rich in dihydromyricetin, the invention aims to provide a preparation method of a dihydromyricetin compound solution capable of being stored stably for a long time.

The invention provides the following technical scheme:

a method for preparing dihydromyricetin complex solution capable of being stably stored for a long time comprises the following steps:

(1) diluting the ethanol solution of dihydromyricetin with water, adding gliadin, and stirring to obtain organic phase;

(2) slowly adding the organic phase into sodium caseinate solution to form dihydromyricetin-protein complex solution, and evaporating ethanol to obtain dihydromyricetin-protein complex solution;

(3) mixing the dioxymyricetin-protein complex with the anionic polysaccharide solution, and adjusting the pH value to be acidic to obtain a dihydromyricetin-protein-polysaccharide complex solution;

(4) homogenizing dihydromyricetin-protein-polysaccharide complex solution under high pressure, and sterilizing to obtain the dihydromyricetin complex solution.

In the technical scheme of the invention, firstly, mixing grain alcohol-soluble protein with an ethanol solution containing dihydromyricetin to obtain an organic phase in which the grain alcohol-soluble protein and the dihydromyricetin are co-dissolved, forming primary embedding of the dihydromyricetin pair, adding the primary embedded dihydromyricetin into a sodium caseinate solution, and performing secondary coating on the dihydromyricetin; then, anionic polysaccharide with negative charges is introduced, the pH value is adjusted to be acidic, and the anionic polysaccharide is coated on the outer side of dihydromyricetin-cereal prolamin-sodium caseinate to form three-layer coating through electrostatic interaction between sodium caseinate and the anionic polysaccharide, so that the compound is endowed with very good dispersion stability in water through a three-layer coating system, and the long-term storage stability of functional drinks and health-care foods containing dihydromyricetin is improved. In the technical scheme of the application, the solvent is evaporated in the step (2), such as vacuum evaporation, and the recovered ethanol can be recycled.

Preferably, the ethanol solution of the dihydromyricetin is obtained by extracting dihydromyricetin in the vine tea raw material through ethanol, and then removing insoluble precipitates, wherein the content of the dihydromyricetin is 30-50 mg/mL.

Preferably, the ampelopsis grossedentata raw material comprises at least one of ampelopsis grossedentata, ampelopsis grossedentata powder, ampelopsis grossedentata extract, ampelopsis grossedentata flavone or ampelopsis grossedentata product rich in dihydromyricetin.

Both can adopt ampelopsis grossedentata extract and dihydromyricetin as the main material among the technical scheme of this application, also can directly extract dihydromyricetin and carry out normal position embedding from ampelopsis grossedentata, but directly adopt the ampelopsis grossedentata raw materials to extract and compare with the dihydromyricetin after the purification, the composition in the ampelopsis grossedentata is complicated, the technical degree of difficulty of dihydromyricetin embedding has been increased, also influence the instability of ampelopsis grossedentata beverage simultaneously, and the technical scheme of this application provides the scheme of the long-term stability of ampelopsis grossedentata drink of pertinence solution richness containing dihydromyri.

As preferred for the process of the present invention, the prolamins include, but are not limited to, zein, rice prolamin, hordein, wheat gliadin.

Preferably, the ethanol volume concentration of the dihydromyricetin ethanol solution diluted by the water in the step (1) is 70-85%; the mass concentration of the cereal prolamin is 1-5%.

Preferably, the mass concentration of the sodium caseinate solution used in the step (2) is 1-8%; the mass of the sodium caseinate and the cereal prolamin is 1: 1-2: 1.

Preferably, the anionic polysaccharide used in step (3) is one or more of sodium carboxymethylcellulose, pectin and soybean polysaccharide, or a compound colloid containing one or more of sodium carboxymethylcellulose, pectin and soybean polysaccharide; the mass ratio of the anionic polysaccharide to the sodium caseinate is 2: 3-1: 1.

Preferably, the method of the invention, the pH value is adjusted by using edible acidity regulator in the step (3); and (4) adjusting the pH value in the step (3) to be 3.5-4.5 at the end point. The edible acid can be selected from citric acid, lactic acid, malic acid, etc.

Preferably, the high-pressure homogenization is a two-stage high-pressure homogenization at 200/50 MPa.

The invention has the following beneficial effects:

the preparation method of the invention obtains a compound solution containing dihydromyricetin, three layers of coatings of the dihydromyricetin are formed by utilizing anionic polysaccharide, sodium caseinate and cereal prolamin, the encapsulation rate of the dihydromyricetin reaches 60-90%, the content of the dihydromyricetin is high, more importantly, the particle size distribution of the compound in the obtained compound solution is uniform, the long-term storage stability is high, the compound solution can be used for preparing functional drinks or beverages, the precipitation of the dihydromyricetin in the low-temperature and normal-temperature storage processes is inhibited, the normal-temperature and low-temperature long-term storage stability of the functional drinks or health-care foods rich in the dihydromyricetin is improved, the precipitation is avoided, the shelf life is prolonged, the process is simple, the energy consumption is low, and the solvent can be recycled.

Drawings

FIG. 1 is a schematic diagram showing a method for preparing a dihydromyricetin complex solution of example 1.

FIG. 2 is a graph showing the particle size distribution of the dihydromyricetin complex solution prepared in example 1 before and after storage at room temperature.

FIG. 3 is a graph showing a comparison of the state of example 1, comparative example and dihydromyricetin aqueous solution after leaving standing under different conditions.

Detailed Description

The following further describes the embodiments of the present invention.

The starting materials used in the present invention are commercially available or commonly used in the art, unless otherwise specified, and the methods in the following examples are conventional in the art, unless otherwise specified.

The encapsulation efficiency in each of the following examples and comparative examples was calculated according to the following formula: encapsulation ratio (%) — content of dihydromyricetin in soluble portion in the complex/total amount of dihydromyricetin added to prepare the complex × 100%.

Example 1

A method for preparing dihydromyricetin complex solution capable of being stored stably for a long time is shown in figure 1, and the preparation process comprises: (1) weighing 5g of ampelopsis grossedentata flavone, fully stirring and dissolving in 100mL of ethanol, and centrifuging for 30min at 4000rpm to remove insoluble precipitate to obtain a dihydromyricetin ethanol solution; adding water to dilute until the volume concentration of ethanol is 80% (v/v), taking 100mL, dissolving zein until the concentration is 4%, and fully stirring and dissolving to prepare an organic phase;

(2) slowly adding 100mL of organic phase into 100mL of sodium caseinate solution with protein concentration of 4% to form dihydromyricetin-protein complex solution, evaporating at 35 deg.C for 45min by vacuum evaporation method to remove ethanol to obtain dihydromyricetin-protein complex, and recovering the evaporated ethanol;

(3) adding water into the dihydromyricetin-protein complex until the total volume is 200mL, uniformly mixing, and centrifuging at 4000rpm for 30min to remove insoluble aggregates; then taking 200mL of centrifugal supernatant solution, adding a sodium carboxymethylcellulose solution with the mass concentration of 2% according to the volume ratio of 1:1, mixing for 15min, and adjusting the pH of the solution to 4.0 by using citric acid to prepare a dihydromyricetin-protein-sodium carboxymethylcellulose compound solution;

(4) homogenizing dihydromyricetin-protein-polysaccharide complex solution under high pressure of 200/50Mpa, and heating in 95 deg.C water bath for 10min for sterilization to obtain dihydromyricetin complex solution.

In the compound solution obtained after sterilization in the step (4) in this example, the average particle size of the particles was 426nm, the dispersion index PDI was 0.248, the Zeta potential was-42.9 mV, and the encapsulation efficiency of dihydromyricetin was 80.4%.

Example 2

This example differs from example 1 in that the sodium caseinate solution has a protein content of 6%, i.e. zein casein and sodium carboxymethylcellulose 2:3: 2.

In this example, the average particle diameter of the dihydromyricetin complex solution was 493nm, the dispersion index PDI was 0.263, the Zeta potential was-41.5 mV, and the dihydromyricetin encapsulation efficiency was 83.4%.

Example 3

The difference between this example and example 1 is that the concentration of the vine tea flavone ethanol solution is low, i.e. 2g vine tea flavone is weighed out and dissolved in 100mL ethanol by stirring, and other preparation steps are the same as example 1.

In this example, the average particle size of the dihydromyricetin complex solution was 475nm, the dispersion index PDI was 0.237, the Zeta potential was-42.2 mV, and the encapsulation efficiency of dihydromyricetin was 85.6%.

Example 4

This example is different from example 1 in that the anionic polysaccharide solution is a soybean polysaccharide solution having a mass concentration of 2%, and the other preparation steps are the same as example 1.

In this example, the average particle size of the dihydromyricetin complex solution was 144nm, the dispersion index PDI was 0.151, and the encapsulation efficiency of dihydromyricetin with a Zeta potential of-10.3 mV was 80.6%.

Example 5

The difference between this example and example 1 is that the anionic polysaccharide solution is a pectin solution with a mass concentration of 2%, and the other preparation steps are the same as those in example 1.

In this example, the average particle size of the dihydromyricetin complex solution was 238nm, the dispersion index PDI was 0.196, and the encapsulation efficiency of dihydromyricetin with a Zeta potential of-26.2 mV was 82.3%.

Example 6

The difference between this example and example 1 is that the dihydromyricetin is derived from the ampelopsis grossedentata extract, the specific method is to dissolve 10g of ampelopsis grossedentata extract and ethanol, extract for 2h under stirring, then centrifuge under 4000rpm to remove insoluble impurities, the supernatant is dihydromyricetin ethanol solution, the anionic polysaccharide solution is soybean polysaccharide solution with mass concentration of 2%, and the rest of the preparation steps are the same as those in example 1.

In this example, the average particle diameter of the dihydromyricetin complex solution was 147nm, the dispersion index PDI was 0.139, the Zeta potential was-23.5 mV, and the encapsulation efficiency of dihydromyricetin was 61.2%.

Example 7

This example is different from example 1 in that dihydromyricetin is derived from ampelopsis grossedentata, and is prepared by grinding ampelopsis grossedentata into ampelopsis grossedentata powder, placing 25g of ampelopsis grossedentata powder into 100mL of ethanol, extracting for 2 hours under stirring, filtering the extract with a 200-mesh screen, centrifuging for 30 minutes at 4000rpm, removing insoluble impurities to obtain a dihydromyricetin ethanol solution, and further, the anionic polysaccharide solution is a soybean polysaccharide solution having a mass concentration of 2%, and the remaining preparation steps are the same as those in example 1.

In this example, the average particle size of the dihydromyricetin solution was 223nm, the dispersion index PDI was 0.216, the Zeta potential was-22.7 mV, and the dihydromyricetin encapsulation efficiency was 79.5%.

Example 8

The difference between this example and example 1 is that the anionic polysaccharide solution is propylene glycol alginate with a mass concentration of 2%, and the other preparation steps are the same as those in example 1.

In this example, the average particle size of the dihydromyricetin solution was 1061nm, the dispersion index PDI was 0.411, the Zeta potential was-16.7 mV, and the encapsulation efficiency of dihydromyricetin was 65.3%.

Comparative example

The difference from example 1 is that the third coating was not carried out using anionic polysaccharide, pH was not adjusted, pH was maintained at 6.5, and 0.5% nisin was added as a bacteriostatic agent to ensure protection from microorganisms during storage.

The composite solution obtained in the comparative example had a particle diameter of 109nm, PDI of 0.112 and a zeta potential of-31.1 mV.

Performance testing

1. The long-term storage property of the dihydromyricetin compound solution

1) The change in the particle size distribution of the dihydromyricetin complex solution prepared in example 1 after storage at room temperature for 3 months is shown in fig. 2, wherein the storage at room temperature is tested to be left standing at 25 ℃. It can be seen from the figure that the particle size distribution does not change much after 3 months of storage at normal temperature, and the composite particles with large particle size (about 1000 nm) are relatively reduced, which is probably because the composite with larger particle size is precipitated in the process of storage and standing, and the whole particle size still maintains a narrow distribution range.

2) The dihydromyricetin compound solution prepared in example 1 and the dihydromyricetin aqueous solution prepared in the comparative example are respectively stored for three months under the condition of normal temperature illumination and three months under the condition of low temperature illumination, the precipitation of each solution is shown in figure 3, wherein the low temperature storage test is standing at 4 ℃; the dihydromyricetin water solution is dihydromyricetin extract solution of Ampelopsis grossedentata flavone, and the mass content of dihydromyricetin reaches 72.4%. And the instantly prepared dihydromyricetin aqueous solution is an aqueous solution at 90 ℃ due to the low solubility of dihydromyricetin. As can be seen from the figure, only a very small amount of sediment was observed after three months of storage at low temperature, and the stability was maintained as a whole, as compared with the immediately prepared composite solution and the comparative example.

2. Long-term storage Properties of Dihydromyricetin Complex solutions of the above examples and comparative examples

1) The dihydromyricetin complex solutions prepared in the above examples and comparative examples were stored at normal temperature for three months and at low temperature for three months, respectively, and then tested for PDI dispersion index and average particle size, and the results are shown in table 1.

TABLE 1 storage results of dihydromyricetin complex solutions of examples and comparative examples

As can be seen from the above table, in the compound solution containing dioxomyricetin prepared by the method, the encapsulation rate of dihydromyricetin is 60-90%, the average particle size of the compound is within the range of 100-600 nm, the dispersibility index is less than 0.3, and the Zeta potential is-10 to-40 mV; and the polysaccharide has good stability after storage at normal temperature and low temperature, the dispersion index is not changed greatly, and meanwhile, in terms of selection of anionic polysaccharide, the sodium carboxymethylcellulose, pectin, soybean polysaccharide and the like have better effects than propylene glycol alginate, and have lower dispersion index, especially on long-term storage effect.

2) The dihydromyricetin complex solution and the pure dihydromyricetin aqueous solution prepared in the above examples and comparative examples were stored under normal temperature illumination for three months and at low temperature for three months, respectively, and then the soluble dihydromyricetin content was measured, and the results are shown in table 2 (corresponding to the samples in fig. 2).

TABLE 2 Dihydromyricetin content in solutions after storage under different conditions for each example and comparative example

In the above table, it can be seen that in the composite solution containing dioxymyricetin prepared by the method of the present invention, the content of soluble dihydromyricetin can reach 7mg/mL, and the loading amounts of different anionic polysaccharide encapsulated composites are different, but no matter under the conditions of normal temperature illumination and low temperature storage, the loss rate of soluble dihydromyricetin in three months is far less than that of non-embedded dihydromyricetin.

The compound solution obtained by the preparation method is an aqueous dispersion system of the dihydromyricetin, namely a phase-change functional drink, so that the influence of the dihydromyricetin can be reduced or eliminated by preparing the functional drink from the compound solution, and the long-term storage stability of the functional drink is improved.