Method for preparing persimmon fruit wine based on mixed fermentation of esterified red yeast rice and yeast

Abstract

The invention belongs to the technical field of fruit wine brewing, and particularly relates to a method for preparing persimmon fruit wine based on mixed fermentation of esterified red yeast rice and yeast. The persimmon wine is prepared by co-inoculating and fermenting persimmon juice with compound saccharomycetes and esterified red yeast rice, wherein the compound saccharomycetes comprise wine-making high-activity dry yeast, yellow wine high-activity dry yeast and saccharomyces cerevisiae. The persimmon wine obtained through the method is rich in variety of volatile flavor substances, the content of alcohol and ester components is remarkably increased compared with a traditional single-strain fermentation method, the fermentation time of the persimmon fruit wine is greatly shortened, the tannin content is reduced, the stability and taste of a wine body are improved, and the persimmon fruit wine is suitable for large-scale production. The variety and content of aromatic compounds in the persimmon fruit wine are increased, and the quality of the persimmon fruit wine is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of fruit wine brewing, and specifically relates to a method for preparing persimmon fruit wine by mixed fermentation of esterified red yeast rice and yeast. Background Art

[0002] Persimmons are rich in various vitamins, flavonoids, amino acids and phenolic substances, and are a nutritious fruit. Moreover, persimmon frost (the white substance on the surface of persimmon skin), persimmon calyx and persimmon leaves all have good medicinal values, with the effects of relieving cough, promoting cardiovascular and cerebrovascular health, enhancing immunity and preventing eye diseases.

[0003] After ripening, persimmons are extremely easy to soften and rot, and the difficulty in storage makes persimmons face a serious problem of overproduction; in addition, the high tannin content in persimmons not only makes the taste of persimmons sour and astringent, but also components such as tannic acid in persimmons will combine with proteins in the stomach to form insoluble complexes, thus weakening the activity of pepsin. These problems have seriously hindered the development of the persimmon industry.

[0004] Therefore, it is necessary to carry out intensive processing on persimmons and develop diversified products to solve the problems of perishable raw materials and difficult sales.

[0005] In order to improve the commercial value of persimmons and promote their diversified consumption patterns, making persimmons into fruit wine shows broad development prospects.

[0006] For example, patents CN107674804A, CN101798555A, CN104651132A, etc. all provide a method for preparing persimmon wine by yeast fermentation. However, in the above-mentioned technologies, single - type yeasts are used for fermentation, and the obtained persimmon fruit wine has a strong astringent taste, poor flavor, long fermentation cycle and low alcohol content.

[0007] Although patents CN105018301A, CN111676109A, etc. use different types of microorganisms to ferment persimmons, there are still problems such as long fermentation cycle and low esterification rate, resulting in poor quality of the wine body and lack of flavor. Summary of the Invention

[0008] To solve the above - mentioned technical problems, the present invention provides a method for preparing persimmon fruit wine by mixed fermentation of esterified red yeast rice and yeast.

[0009] The method for preparing persimmon fruit wine by mixed fermentation of esterified red yeast rice and yeast provided by the present invention specifically uses compound yeast and esterified red yeast rice to co - inoculate and ferment persimmon juice to prepare persimmon wine.

[0010] The compound yeast described above includes high-activity dry yeast for brewing (EC), high-activity dry yeast for yellow rice wine (Aq), and wine yeast for red wine (F33), and the weight ratio of EC:Aq:F33 is 1-5:1-5:1-10. The mass-volume ratio of the compound yeast to persimmon juice is 0.2-1.5 g:1 L, and the inoculation concentration of esterified red koji is ≥5.7×10 6 CFU / mL, and the inoculation mass of esterified red koji accounts for 1.0%-5.0% of the mass of persimmon juice.

[0011] Preferably, in the above method, during co-inoculation fermentation, the sugar degree of persimmon juice is 20-35°Brix, the pH is 3.0-5.0, and the fermentation temperature is 20-30°C.

[0012] Furthermore, the method for preparing persimmon fruit wine based on the mixed fermentation of esterified red koji and yeast provided by the present invention includes the following steps:

[0013] (1) Screening raw materials, freezing and deastringenting, and thawing and pulping to obtain persimmon pulp;

[0014] (2) Enzymatic hydrolysis: Using pectinase to perform enzymatic hydrolysis on the persimmon pulp obtained in (1), and filtering after enzymatic hydrolysis to obtain persimmon juice;

[0015] (3) Composition adjustment: Adding sodium metabisulfite to the persimmon juice obtained in (2), the added weight of sodium metabisulfite per kilogram of persimmon juice is 50-80 mg, and then adjusting the sugar degree of persimmon juice to 20-35°Brix and the pH to 3.0-5.0;

[0016] (4) Co-inoculation fermentation: Adding compound yeast and esterified red koji to the persimmon juice after composition adjustment in (3) for co-inoculation fermentation;

[0017] (5) Post-treatment: After the fermentation in (4) is completed, obtaining persimmon fruit wine through precipitation and clarification.

[0018] Preferably, in (2), the added weight of the pectinase described accounts for 1.2‰-2.0‰ of the weight of the persimmon pulp, and the enzymatic hydrolysis duration is 3-5 h.

[0019] Preferably, in (3), the sugar degree of the persimmon wine is adjusted to 20-25°Brix.

[0020] Preferably, in (4), the compound yeast is activated before fermentation. The activation specifically is to mix the compound yeast with 2%-3% sterile glucose water at a weight ratio of 1:8-15, stir evenly, and let it stand for 20-30 min.

[0021] Preferably, in (4), the esterified red koji is activated first and then co-inoculated.

[0022] The activation operation of the esterified red yeast rice is as follows: First, dilute the esterified red yeast rice spore suspension to a concentration of 5.7×10 3 CFU / mL, and then inoculate the spore suspension into the seed medium for cultivation. The inoculation volume of the spore suspension is 12-20% of the volume of the seed medium, and it is cultivated at a temperature of 30-40°C for 24-48 hours.

[0023] The beneficial effects of the present invention are as follows:

[0024] (1) The method provided by the present invention for co-fermenting esterified red yeast rice with complex yeast significantly improves the enzyme activity of esterified red yeast rice, accelerates the synthesis of esters in persimmon wine, is beneficial to shortening the fermentation cycle and enhancing the flavor of the wine body;

[0025] (2) Compared with using single yeast or complex yeast for fermentation, on the one hand, the types and contents of volatile flavor substances such as alcohols and esters in the persimmon wine obtained by co-fermenting esterified red yeast rice with complex yeast have both increased. The active components are as high as 32 kinds, far higher than those of complex yeast fermentation (27 kinds), single Aq fermentation (20 kinds), single EC fermentation (21 kinds), and single F33 fermentation (19 kinds), greatly enriching the flavor and aroma of persimmon wine; on the other hand, the contents of various flavor substances in the persimmon wine are relatively balanced, and there is no situation where one or several flavor substances account for too high a proportion. This balance makes the taste of the wine softer and not overly single or stimulating;

[0026] (3) Compared with the traditional fermentation methods of red yeast rice or Aspergillus niger, the esterified red yeast rice and complex yeast adopted in the present invention have stronger stability and compatibility, are heat-resistant and can adapt to complex fermentation environments, and at the same time have lower costs. Description of the Drawings

[0027] Figure 1 It shows the change of the total ester content in persimmon wine under different inoculation amounts of esterified red yeast rice in Example 3 of the present invention;

[0028] Figure 2 It shows the change of the total ester content in persimmon wine with different initial sugar degrees in Example 4 of the present invention;

[0029] Figure 3 It shows the change of the total ester content in persimmon wine under different fermentation temperatures in Example 5 of the present invention;

[0030] Figure 4 It shows the change of the total ester content in persimmon wine under different fermentation durations in Example 6 of the present invention;

[0031] Figure 5 It shows the change of the total ester content in persimmon wine under different fermentation pH values in Example 7 of the present invention. Detailed Embodiments

[0032] In order to enable those skilled in the art to better understand the present invention, the present invention will be further elaborated below in conjunction with specific embodiments.

[0033] Example 1

[0034] A method for preparing persimmon fruit wine by mixed fermentation of esterified Monascus and yeast, comprising the following steps:

[0035] (1) Select fresh persimmons picked from Changqing District, Jinan City, Shandong Province, remove bad and rotten fruits, perform freezing and deastringency, thaw the frozen and deastringent persimmons at room temperature, remove the pedicles after thawing, wash and dry, and then perform pulping treatment with a pulper to obtain persimmon pulp;

[0036] (2) Enzymatic hydrolysis: Heat the persimmon pulp obtained in (1) to 43 °C, then add pectinase accounting for 1.6‰ of the weight of the persimmon pulp and perform enzymatic hydrolysis for 3.5 h. After enzymatic hydrolysis, filter to obtain persimmon juice. The juice yield of persimmons is 70.83%, and at this time, the sugar content of the persimmon juice is 13.5 °Brix and the pH value is 3.8;

[0037] (3) Component adjustment: Add potassium metabisulfite to the persimmon juice obtained in (2). The addition amount of potassium metabisulfite per kilogram of persimmon juice is 60 mg, and add granulated sugar to adjust the sugar content of the persimmon juice to 24 °Brix, and use sodium carbonate to adjust the pH to 4.0;

[0038] (4) Co-inoculation fermentation

[0039] First, mix high-activity dry yeast for brewing (EC), high-activity dry yeast for yellow rice wine (Aq), and wine yeast for red wine (F33) in a weight ratio of 4:4:7 to obtain a composite yeast. Take 0.3 g of the composite yeast and mix it with 2% sterile glucose water in a weight ratio of 1:10, stir evenly, let it stand and activate at 38 °C for 30 min, and then add it to 1 L of persimmon juice to be fermented;

[0040] Next, dilute the esterified Monascus spore suspension to a concentration of 5.7×10 3 CFU / mL. Subsequently, inoculate 15% of the spore suspension into 200 mL of seed medium, culture it at 30 °C and 160 r / min for 36 h for activation. Take the activated esterified Monascus and inoculate it into the above-mentioned persimmon juice according to an inoculation mass of 1.5% for co-inoculation fermentation. During co-inoculation, the concentration of esterified Monascus is 5.7×10 6 CFU / mL. The temperature of co-inoculation fermentation is 22.5 °C, and terminate the fermentation after 10 days of fermentation. The detected alcohol content is 11.5% V / V;

[0041] (5) Post-treatment: After the fermentation in (4) is completed, sedimentation and clarification are carried out, and 60 mg / kg of sodium metabisulfite is added to obtain the described persimmon fruit wine, which is stored at low temperature. The esterified red yeast used in this example is a high-esterase-producing Monascus purpureus strain ZH-3, which is acid-resistant at pH 3.5 or above, alcohol-resistant up to 11%, and has good stability.

[0042] The persimmon fruit wine obtained by the method of this example has the unique flavor of persimmons, with a full-bodied, mellow, pure, elegant, refreshing and clean taste, harmonious fruit and wine aromas, rich aroma, pleasant and long-lasting, good clarity, bright and attractive color.

[0043] The experimental results show that the light transmittance of the persimmon fruit wine is 90.13%, the total ester is 3.72 g / L, the total acid is 5.4 g / L, the total sugar is 16.90 g / L, and the average score of the sensory evaluation is 90.9 points.

[0044] In addition, when the inventor conducted experiments, commercially available esterified red yeast was also used and the effect of its co-fermentation in preparing persimmon wine was verified. There was no significant difference in the total score of the obtained persimmon wine compared with that of this strain, and the content of active ingredients in the persimmon fruit wine was only slightly lower than that of this strain.

[0045] Example 2

[0046] This example focuses on exploring the influence of the inoculation mass ratio of compound yeast on the quality of persimmon wine. Different from Example 1, the inoculation mass ratio of compound yeast in (4) is shown in Table 1.

[0047] Table 1 Optimization of different yeast mixed ratios

[0048]

[0049]

[0050] Taking the weight loss of CO 2 as an index to judge the fermentation rate, and at the same time using the residual sugar content to evaluate the utilization efficiency of the mixed bacteria, evaluating the effect of mixed bacteria fermentation, and finally comprehensively analyzing the CO 2 weight loss and residual sugar data to screen the optimal mixed bacteria ratio.

[0051] The results show that different yeast mixed fermentation has a significant influence on the fermentation rate of persimmon wine. Compared with single-strain fermentation, the fermentation rate after mixed yeast fermentation shows an obvious increase. Especially, the CO 2 weight losses of the three ratios of 4:4:7, 3:1:1, and 1:1:1 all exceed 10 g, showing strong fermentation ability. After analyzing the residual sugar data, it is found that when EC, Aq, and F33 are mixed in a mass ratio of 4:4:7, the residual sugar value reaches the minimum, indicating that the sugar in persimmons has been more thoroughly converted.

[0052] Example 3

[0053] This example focuses on exploring the influence of the inoculation quality of esterified Monascus on the quality of persimmon wine. Different from Example 1:

[0054] (4) Without adding the mixed yeast, adjust the initial sugar content of the persimmon juice to 20°Brix and the pH value to 3.8. Then, inoculate esterified Monascus at different inoculation amounts of 1%, 2%, 3%, 4%, and 5%, and culture at 24°C for 8 days. Measure the total ester content of the persimmon wine obtained in each experimental group to determine the optimal inoculation amount of esterified Monascus.

[0055] The total ester content of the persimmon wine obtained under different inoculation amounts of esterified Monascus is shown in the appendix Figure 1 as follows.

[0056] Figure 1 As can be seen from the appendix, the total ester content shows a trend of first increasing and then decreasing with the increase of the inoculation amount of esterified Monascus. When the addition amount of esterified Monascus < 3%, the total ester content increases with the increase of the addition amount of esterified Monascus, indicating that appropriately increasing the addition amount of esterified Monascus can promote the fermentation process, produce rich fruity aroma and complex flavors, thereby improving the yield and quality of the wine. When the addition amount of esterified Monascus > 3%, the total ester content decreases with the increase of the addition amount of esterified Monascus, and excessive use of esterified Monascus may cause off-flavors in the food, and even promote the growth of some harmful microorganisms, resulting in the production of harmful substances such as nitrite. When the addition amount of esterified Monascus is 3%, the total ester content is the highest, which is 3.18 g / L. Therefore, 3% is selected as the optimal inoculation amount of esterified Monascus.

[0057] Example 4

[0058] This example focuses on exploring the influence of the initial sugar content on the quality of persimmon wine. Different from Example 1:

[0059] (4) Without adding the mixed yeast, adjust the inoculation amount of esterified Monascus in the persimmon juice to 3% and the pH to 3.8. Adjust the initial sugar contents to 12, 16, 20, 24, and 28°Brix respectively, and after culturing at a constant temperature of 24°C for 8 days, measure the total ester content of the persimmon wine obtained in each experimental group to determine the optimal initial sugar content. The experimental results are shown in the appendix Figure 2 as follows.

[0060] The results show that for persimmon wines with different initial sugar degrees, the total ester content first increases and then decreases as the initial sugar degree increases. When the initial sugar degree is <24°Brix, as the initial sugar degree increases, the total ester content shows an increasing trend, indicating that as the sugar degree increases, the metabolic activities of esterifying Monascus and the activity of enzymes are promoted, which is beneficial to the esterification reaction. When the initial sugar degree >24°Brix, as the sugar degree increases, the total ester content decreases. This may be because the metabolism of esterifying Monascus is inhibited by the excessive sugar degree, thus reducing the rate and efficiency of the esterification reaction. When the initial sugar degree is 24°Brix, the total ester content reaches the maximum value of 3.38 g / L, and the optimal initial sugar degree is finally determined to be 24°Brix.

[0061] Example 5

[0062] This example focuses on exploring the influence of fermentation temperature on the quality of persimmon wine. Different from Example 1:

[0063] (4) In this case, no mixed yeast is inoculated. The inoculation amount of esterifying Monascus in persimmon juice is adjusted to 3%, the pH is 3.8, and the initial sugar degree is 24°Brix. They are respectively placed at fermentation temperatures of 20, 24, 28, 32, and 36 °C. After constant temperature cultivation for 8 days, the total ester content of the persimmon wines obtained from each experimental group is measured to determine the optimal temperature. The results are as shown in the appendix Figure 3 as follows.

[0064] Figure 3 (The results) show that when the fermentation temperature rises, the total ester content first increases, then reaches a peak at 24 °C and then starts to decline, but then shows a new increasing trend. Among them, at fermentation temperatures of 24 °C and 36 °C, the total ester content of the persimmon wine is relatively high. Temperature is one of the key factors affecting the quality of persimmon wine, and its change has a significant impact on the flavor, taste, and storage stability of the wine body. Under high-temperature conditions, the aroma and flavor substances in the fruit wine are easily volatilized excessively, resulting in damage to the flavor of the persimmon wine. When the fermentation temperature is 24 °C, the total ester content is 3.65 g / L.

[0065] Example 6

[0066] This example focuses on exploring the influence of the fermentation duration of co-inoculation fermentation on the quality of persimmon wine. Different from Example 1:

[0067] (4) In this case, the inoculation amount of compound yeast in persimmon juice is adjusted to 0.3 g / kg, the pH is 3.8, the initial sugar degree is 24°Brix, and the fermentation temperature is 24 °C. The fermentation time is adjusted to 0, 2, 4, 6, 8, 10, and 12 days. The total ester content of the persimmon wines obtained from each experimental group is measured to determine the optimal fermentation time. The experimental results are as shown in the appendix Figure 4 as follows.

[0068] Appendix Figure 4As shown, insufficient fermentation time may lead to incomplete esterification reaction, resulting in the total ester content not reaching the ideal level; too long fermentation time may cause a decrease in the activity of esterified Monascus, thereby affecting the progress of the esterification reaction, making the increase rate of the total ester gradually slow down. When the fermentation continues to the 10th day, the total ester content reaches the highest point, which is 3.52 g / L.

[0069] Example 7

[0070] This example focuses on exploring the influence of the pH value during co-inoculation fermentation on the quality of persimmon wine. Different from Example 1:

[0071] (4) In this example, the inoculation amount of compound yeast in persimmon juice was adjusted to 0.3 g / kg, the initial sugar degree was 24 °Brix, and the pH was adjusted to 3.0, 3.4, 3.8, 4.2, and 4.6. After culturing at a constant temperature of 24 °C for 8 days, the total ester content of the persimmon wine obtained in each experimental group was measured to determine the optimal pH. The results are shown in the appendix Figure 5 as follows. Figure 5 The results in the appendix show that as the pH increases, the total ester content shows a trend of first increasing and then decreasing. When pH < 4.2, the total ester content increases with the increase of pH. When the pH is 4.2, the total ester content is the highest, which is 3.01 g / L. When pH > 4.2, the total ester content shows a downward trend, indicating that during the fermentation process of persimmon wine, pH = 4.2 is more suitable for the growth and reproduction of esterified Monascus.

[0072] Example 8

[0073] This example focuses on exploring the interactive influence of the inoculation amount of esterified Monascus, fermentation temperature, and pH during co-inoculation fermentation on the quality of persimmon wine. Different from Example 1:

[0074] (4) In this example, the inoculation amount of compound yeast in persimmon juice was adjusted to 0.3 g / kg, the initial sugar degree was 24 °Brix, the addition amount of esterified Monascus was adjusted to 0, 1.5%, and 3%, the fermentation temperature was 20 °C, 22 °C, and 24 °C, and the fermentation pH was 3.8, 4.0, and 4.2. After culturing at a constant temperature for 10 days, the persimmon wine obtained in each experimental group was subjected to sensory evaluation to determine the optimal co-fermentation parameters. The DesignExpert software was used to perform regression fitting analysis on the data in Table 2 to obtain the relevant data of the quadratic regression analysis, perform quadratic multiple regression fitting analysis on the experimental data, and obtain the quadratic multiple fitting regression equation: Y = 90.80 + 1.53A + 0.01B - 0.46C - 0.95AB + 1.70AC - 1.22BC - 1.91A 2 -2.99B 2 -1.39C 2The optimal conditions for the production of persimmon wine by mixed culture fermentation can be obtained by solving the quadratic polynomial fitting regression equation. The optimal conditions are A (Monascus addition amount) = 1.56%, B (temperature) = 22.57 °C, C (pH) = 3.97. The theoretical value of the sensory score of persimmon wine fermented by compound multi-strain is expected to be 90.70 points. Considering the actual operation of the experiment, a verification experiment was carried out under the conditions of A (Monascus addition amount) 1.50%, B (temperature) 22.5 °C, and C (pH) 4.0. Finally, the average value of the sensory evaluation score was 90.9 points, which was roughly consistent with the predicted value.

[0075] Analysis of variance was carried out on the regression model of the sensory evaluation of persimmon wine, and the results are shown in Tables 2 and 3. Among them, the quadratic term A 2 and the quadratic term C 2 have significant effects (P < 0.05), the linear term A and the quadratic term B 2 have extremely significant effects (P ≤ 0.01), the interaction term AC has an obvious interaction, and the interaction of the remaining interaction terms is not obvious. At the same time, from the F value in the table, it can be seen that among the three factors, the addition amount of Monascus (A) has the greatest influence on the sensory evaluation, and the temperature (B) has the least influence on the sensory evaluation.

[0076] Table 2 Box-Behnken experimental design and results

[0077]

[0078]

[0079] Table 3 Box-Behnken experimental design and results

[0080]

[0081] Comparative Example 1

[0082] Different from Example 1, only a single high-activity dry yeast for brewing, or high-activity dry yeast for yellow rice wine, or wine yeast for red wine was used for fermentation.

[0083] Comparative Example 2

[0084] Different from Example 1, esterified Monascus was not used for co-fermentation.

[0085] The contents of alcohol and ester volatile components in the persimmon wine obtained by using the above different fermentation methods are shown in Table 4 below.

[0086] Table 4 Analysis table of alcohol and ester volatile components in persimmon wine

[0087]

[0088]

[0089]

[0090] As can be seen from the above results, 32 compounds were detected in the persimmon wine fermented by the mixed fermentation of esterified red yeast rice and complex yeast. Among them, there were 10 alcohols, 10 esters, 9 aldehydes and ketones, and 3 others; only 27 compounds were detected in the persimmon wine fermented by complex yeast alone. Among them, there were 7 alcohols, 15 esters, 2 aldehydes and ketones, and 3 others; the types of compounds in the persimmon wine fermented by single Aq, EC, and F33 yeast were only 20, 21, and 19 respectively.

[0091] The new alcohols in the process of mixed fermentation with esterified red yeast rice and complex yeast include tridecanol, n-decanol, 4-terpineol, nonanediol, lauryl alcohol, and geranylgeraniol. Compared with other fermentation methods, the types and contents of volatile flavor substances such as alcohols, esters, aldehydes and ketones produced by the co-inoculation fermentation of complex yeast and esterified red yeast rice are further increased. Especially, the relative content of alcohol substances has been significantly improved. Among the alcohol substances, phenethyl alcohol with a rose fragrance is the main alcohol, enriching the flavor and aroma of persimmon wine.

[0092] Esters are formed by the reaction of higher alcohols and fatty acids under the catalysis of enzymes, endowing the wine body with various aromas such as fruity, floral, and sweet, greatly enhancing the complexity, diversity and pleasure of the wine body, making the persimmon wine fermented by complex strains more unique and charming in flavor. Aldehydes and ketones are important flavor components, which can play a role in assisting fragrance and presenting taste, giving people a pleasant sensory enjoyment.

[0093] Furthermore, in the persimmon wine obtained by using the co-mixed fermentation method of the present invention, the contents of various flavor substances are relatively balanced, and there is no situation where one or several flavor substances account for too high a proportion. This balance makes the taste of the wine more mellow and not too single or stimulating; in addition, the contents of each substance are relatively balanced. For example, among the alcohol compounds, although phenethyl alcohol has the highest proportion, other alcohol compounds such as active amyl alcohol and 2,3-butanediol also have a certain proportion; among the ester compounds, phenethyl acetate, ethyl octanoate, etc. also have a relatively balanced proportion.

Claims

1. A method for preparing persimmon wine based on mixed fermentation of esterified red yeast rice and yeast, characterized in that: The composite yeast and esterified red yeast are used to co-inoculate and ferment persimmon juice to prepare persimmon wine; the composite yeast comprises high-activity dry yeast for brewing wine, high-activity dry yeast for yellow wine, and red wine brewing yeast, and the weight ratio of high-activity dry yeast for brewing wine: high-activity dry yeast for yellow wine: red wine brewing yeast is 1-5:1-5:1-10, the mass volume ratio of the composite yeast to persimmon juice is 0.2-1.5 g:1 L, and the inoculation concentration of the esterified red yeast is ≥5.7×10 6 CFU / mL, the inoculum mass of esterified red yeast rice accounted for 1.0%~5.0% of the mass of persimmon juice.

2. The method for preparing persimmon wine based on mixed fermentation of esterified red yeast and yeast according to claim 1, characterized in that: During co-inoculation fermentation, the sugar content of persimmon juice is 20~35°Brix, the pH is 3.0~5.0, and the fermentation temperature is 20~30℃.

3. The method for preparing persimmon wine based on mixed fermentation of esterified red yeast and yeast according to claim 1, characterized in that: The steps include: (1) Raw material selection, freezing to remove astringency, thawing and beating to obtain persimmon pulp; (2) Enzymatic hydrolysis: using pectinase to enzymatically hydrolyze the persimmon pulp obtained in (1), and filtering after enzymatic hydrolysis to obtain persimmon juice; (3) Ingredient adjustment: adding sodium metabisulfite to the persimmon juice obtained in (2), wherein the added weight of sodium metabisulfite is 50-80 mg per kilogram of persimmon juice, and then adjusting the sugar content of the persimmon juice to 20-35° Brix and the pH to 3.0-5.0; (4) Co-inoculation fermentation: adding the composite yeast and esterified red yeast rice to the persimmon juice after the ingredients are adjusted in (3) to carry out co-inoculation fermentation of the persimmon juice; (5) Post-treatment: After the fermentation in (4) is completed, persimmon wine is obtained by sedimentation and clarification.

4. The method for preparing persimmon wine based on mixed fermentation of esterified red yeast and yeast according to claim 3, characterized in that: The added weight of the pectinase described in (2) accounts for 1.2‰~2.0‰ of the weight of the persimmon pulp, and the enzymolysis time is 3~5 h.

5. The method for preparing persimmon wine based on mixed fermentation of esterified red yeast and yeast according to claim 3, characterized in that: (3) Adjust the sugar content of the persimmon wine to 20~25°Brix.

6. The method for preparing persimmon wine based on mixed fermentation of esterified red yeast and yeast according to claim 3, characterized in that: In (4), the composite yeast is activated before fermentation. Specifically, the composite yeast is mixed with 2% to 3% sterile glucose water at a weight ratio of 1:8 to 15, stirred evenly, and allowed to stand for 20 to 30 minutes.

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