Polypeptide enhanced yellow rice wine and brewing method thereof

Abstract

The invention relates to the technical field of food fermentation, in particular to polypeptide enhanced yellow rice wine and a brewing method thereof. According to the method, yarrowia lipolytica and saccharomyces cerevisiae with high erythritol yield are introduced in the yellow wine brewing process for synergistic fermentation (main fermentation-intermittent ventilation fermentation and post fermentation-anaerobic fermentation), so that the content of polypeptide is remarkably increased, and the amino acid composition is optimized; meanwhile, the taste of the wine body is naturally improved by utilizing a metabolic product, namely erythritol, of yarrowia lipolytica, and the bitter taste of the yellow wine is effectively reduced. Compared with the prior art, the yellow wine provided by the invention has the advantages that not only is the nutritional function obviously improved, but also the flavor characteristic can be improved, no additional sweetening agent or complex process is needed, and the yellow wine has higher technical advancement and industrial application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of food fermentation, and in particular to a polypeptide-enhanced yellow rice wine and a brewing method thereof. BACKGROUND

[0002] Yellow rice wine, as a traditional Chinese liquor with a long history, is usually produced by microbial fermentation using grains such as rice, wheat, and corn as raw materials. Yellow rice wine is not only loved for its unique flavor but also has certain health functions. With the modern people's attention to healthy diet, the nutritional value and functionality of yellow rice wine have increasingly become the focus of scientific research and the market. The traditional brewing process of yellow rice wine usually includes steps such as steaming grains, saccharification, and fermentation, among which fermentation is the most critical link. During fermentation, microorganisms such as yeast and aspergillus play a role in decomposing starch and protein in the raw materials into compounds such as polysaccharides, amino acids, peptides, and alcohol. Yellow rice wine is rich in various amino acids and small peptides, which not only give yellow rice wine a unique taste and aroma but also have certain nutritional and biological activities. However, traditional yellow rice wine still has certain deficiencies in terms of flavor and nutritional function, which restricts its further industrial upgrading and consumer acceptance.

[0003] As one of the important components in yellow rice wine, polypeptides are mainly derived from the enzymatic action of microorganisms such as aspergillus on proteins. These polypeptides are not only important components of nutritional substances but also have potential functional activities in regulating the body's immune system, antioxidant, and anti-fatigue. In recent years, studies have shown that yellow rice wine rich in polypeptides has obvious functional food properties and can play an active role in regulating blood sugar, delaying aging, and improving intestinal health. However, due to the limited control ability of the traditional brewing process on the protein degradation pathway, the yield and variety of polypeptides are difficult to meet the needs of functional yellow rice wine development. In addition, there is a certain bitter taste in the flavor composition of yellow rice wine, mainly derived from bitter amino acids (such as valine, leucine, isoleucine, etc.) and certain phenolic substances. Excessive bitterness often reduces the taste harmony of yellow rice wine, which is not conducive to the acceptance of young consumers. Although some distilleries try to reduce bitterness through process improvement (such as aging, blending, or post-treatment technology), the effect is limited, and it may bring additional costs or adversely affect the overall flavor of yellow rice wine.

[0004] The yeast strain used in traditional yellow rice wine production is mainly Saccharomyces cerevisiae, which mainly functions to convert sugar into alcohol and part of the flavor substances, and does not have significant erythritol synthesis ability. Simply relying on process improvement to enhance sweetness and reduce bitterness often fails to achieve the dual optimization of nutrition and taste.

[0005] Therefore, it is crucial to provide a technical solution that can solve the above problems. SUMMARY

[0006] To solve the above problems, the purpose of the present application is to provide a polypeptide enhanced yellow rice and its brewing method. The present application uses Yarrowia lipolytica with high erythritol production and Saccharomyces cerevisiae to co-ferment (main fermentation-intermittent aeration fermentation and post-fermentation-anaerobic fermentation) functional yellow rice. The present application introduces Yarrowia lipolytica (in the case of co-fermentation with Saccharomyces cerevisiae) in the production process of yellow rice, which not only promotes the hydrolysis of proteins and the generation of polypeptides, but also makes the yellow rice rich in various functional polypeptides. More importantly, the erythritol produced by the Yarrowia lipolytica metabolism can be used as a natural sweetener, and the synergistic effect with sweet amino acids can give the yellow rice a more soft and smooth flavor characteristic without relying on additional additives.

[0007] The purpose of the present application can be achieved by the following technical solutions: The first purpose of the present application is to provide a brewing method of polypeptide enhanced yellow rice, comprising the following steps: (S1) adding pretreated grain raw materials to malt for saccharification treatment to obtain saccharified materials; (S2) inoculating the saccharified materials obtained in step (S1) with yeast fermentation broth, then performing fermentation treatment, and post-treatment to obtain polypeptide enhanced yellow rice; Wherein, the fermentation broth is a mixed bacteria broth of Saccharomyces cerevisiae bacteria broth and Yarrowia lipolytica bacteria broth; fermentation includes main fermentation and post-ripening fermentation (for promoting erythritol accumulation); The main fermentation process is carried out under intermittent aeration conditions, and the post-ripening fermentation process is carried out under anaerobic conditions; The content of erythritol in the polypeptide enhanced yellow rice is 4-8 g / L.

[0008] In an embodiment of the present application, in step (S1), the grain raw material is rice grain, or a mixture of rice grain and bean grain; The rice grain is selected from one or more of waxy rice, millet, rice, highland barley or quinoa; The bean grain is selected from one or more of black beans, green beans or red beans.

[0009] In an embodiment of the present application, in step (S1), the pretreatment is as follows: The grain raw material is washed, soaked, and cooked, and then cooled to 28-30 ℃.

[0010] In an embodiment of the present application, the soaking time is 6-8 h, and the cooking time is 15 min-2 h.

[0011] In an embodiment of the present application, in step (S1), the mass ratio of the grain raw material to malt is 5-10:1.

[0012] In one embodiment of the present application, in step (S1), the temperature during the saccharification process is 28-30℃, and the time is 0-48h.

[0013] In one embodiment of the present application, in step (S2), the ratio of the number of cells of Saccharomyces cerevisiae to that of Yarrowia lipolytica in the fermentation broth is 1:5-10, and the inoculation amount of the fermentation broth is 1x10 7 CFU / mL; The Saccharomyces cerevisiae is Saccharomyces cerevisiae with the preservation number of CGMCC No. 12787, and the Yarrowia lipolytica is Yarrowia lipolytica with the preservation number of ATCC 20362.

[0014] In one embodiment of the present application, in step (S2), during the main fermentation process, the pH is 4.0-4.5, the temperature is 28-30℃, and the time is 3-8 days.

[0015] In one embodiment of the present application, in step (S2), during the post-ripening fermentation process, the pH is 4.0-4.5, the temperature is 28-30℃, and the time is 10-20 days.

[0016] In one embodiment of the present application, in step (S2), the post-treatment is specifically as follows: After the fermentation is completed, the product is sequentially subjected to pressing, filtration, clarification and decoction.

[0017] The polypeptide-enhanced yellow rice provided by the present application (introducing high-erythritol-producing Yarrowia lipolytica and conventional yellow rice yeast for synergistic fermentation during the fermentation process of yellow rice) not only significantly increases the types and content of polypeptides in yellow rice (increasing by 20-35%), especially small-molecule active polypeptides with a molecular weight of 500-1000 Da, but also increases the content of sweet amino acids (increasing by 15-30%), and metabolically generates 4-8 g / L of erythritol, thereby effectively reducing the bitterness of yellow rice and making the flavor of the wine body more soft and harmonious. Compared with the prior art, the present application can balance the nutritional function and taste improvement without additional sweeteners or complex post-treatment processes, and has significant technical progress and industrial application value.

[0018] The second object of the present application is to provide a polypeptide-enhanced yellow rice prepared by the above method.

[0019] Compared with the prior art, the present application has the following beneficial effects: (1) The present application promotes the more efficient decomposition of proteins in raw materials into polypeptides and amino acids through the synergistic fermentation of Yarrowia lipolytica and Saccharomyces cerevisiae, significantly increases the polypeptide content in yellow rice, and endows yellow rice with potential immune regulation and antioxidant functions; (2) The present application utilizes the erythritol metabolic advantage of Yarrowia lipolytica to increase the content of natural sweet substances in yellow rice wine, improve the proportion of sweet amino acids (soft sweet taste), effectively mask the bitter taste caused by the imbalance of amino acids in traditional yellow rice wine (reduced bitter taste), and improve the overall flavor (significantly improved overall taste coordination); (3) The production process provided by the present application is highly compatible with traditional yellow rice wine brewing, does not require additional expensive equipment, and is suitable for industrialization and popularization. In addition, the method is not only suitable for yellow rice wine production, but also can be expanded to the development of other grain fermented beverages or functional fermented foods, providing a new technical path for the upgrading of traditional brewing industry and the innovation of functional foods.

[0020] Overall, by introducing Yarrowia lipolytica with high erythritol production into the fermentation of yellow rice wine, the present application not only solves the technical problems of low polypeptide content, insufficient sweet amino acids, and heavy bitter taste in traditional yellow rice wine, but also realizes the dual optimization of nutritional value and flavor characteristics, which has significant technical progress and industrial application value. DETAILED DESCRIPTION

[0021] The present application will be described in detail below in conjunction with specific examples.

[0022] In the following examples, the grain raw materials used are high-quality glutinous rice, which is cleaned and soaked before use; the wheat starter is traditional yellow rice wine wheat starter containing Aspergillus, Rhizopus and lactic acid bacteria; the wine yeast is Saccharomyces cerevisiae (BR129f23 strain, preservation number CGMCC No. 12787), and Yarrowia lipolytica is purchased from the American Type Culture Collection (ATCC), with preservation number ATCC 20362 (isolated from dairy products). Saccharomyces cerevisiae

[0023] Unless otherwise specified, all reagents used are commercially available, and all detection means and methods used are conventional detection means and methods in the art.

[0024] Example 1 The present embodiment provides a brewing method for polypeptide-enhanced yellow rice wine, as follows: 20 kg of glutinous rice was cleaned and soaked for 7 h, then cooked under normal pressure for 25 min (until the rice was soft but not rotten), and then quickly removed and cooled to 30℃ for standby after there was no white core, obtaining pretreated glutinous rice; The pretreated grain raw materials were added with 3.5 kg of yellow rice wine wheat starter for saccharification treatment, and mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (bacterial number ratio of Saccharomyces cerevisiae to Yarrowia lipolytica 8:1, total amount 1×10 7 ​CFU / mL), and then fermentation treatment (28℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0025] Example 2 The present embodiment provides a polypeptide-enhanced yellow rice wine brewing method, which is specifically as follows: The 20 kg of waxy rice was cleaned and soaked for 7 hours, and then cooked under normal pressure for 25 minutes (until the rice was soft but not rotten). After the white core was removed, the rice was quickly cooled to 30℃ for standby, and the pretreated waxy rice was obtained. The pretreated cereal raw materials were added with 3.5 kg of yellow rice wheat koji for saccharification treatment, and the mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (the ratio of the number of Saccharomyces cerevisiae to Yarrowia lipolytica was 5:1, and the total amount was 1×10 7 CFU / mL), and then fermentation treatment (28℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0026] Example 3 The present embodiment provides a polypeptide-enhanced yellow rice wine brewing method, which is specifically as follows: The 20 kg of waxy rice was cleaned and soaked for 7 hours, and then cooked under normal pressure for 25 minutes (until the rice was soft but not rotten). After the white core was removed, the rice was quickly cooled to 30℃ for standby, and the pretreated waxy rice was obtained. The pretreated cereal raw materials were added with 3.5 kg of yellow rice wheat koji for saccharification treatment, and the mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (the ratio of the number of Saccharomyces cerevisiae to Yarrowia lipolytica was 5:1, and the total amount was 1×10 7CFU / mL), and then fermentation treatment (26℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0027] Example 4 The present example provides a polypeptide-enhanced yellow rice wine brewing method, which is specifically as follows: The 20 kg of waxy rice was cleaned and soaked for 7 hours, and then cooked under normal pressure for 25 minutes (until the rice was soft but not rotten). After the white core was removed, the rice was quickly removed and cooled to 30℃ for standby, and the pretreated waxy rice was obtained. The pretreated cereal raw materials were added with 3.5 kg of yellow rice wheat starter for saccharification treatment. After saccharification for 4 hours, the mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (the ratio of the number of Saccharomyces cerevisiae to Yarrowia lipolytica was 8:1, and the total amount was 1×10 7 CFU / mL), and then fermentation treatment (26℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0028] Example 5 The present example provides a polypeptide-enhanced yellow rice wine brewing method, which is specifically as follows: The 20 kg of waxy rice was cleaned and soaked for 7 hours, and then cooked under normal pressure for 25 minutes (until the rice was soft but not rotten). After the white core was removed, the rice was quickly removed and cooled to 30℃ for standby, and the pretreated waxy rice was obtained. The pretreated cereal raw materials were added with 3.5 kg of yellow rice wheat starter for saccharification treatment. After saccharification for 4 hours, the mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (the ratio of the number of Saccharomyces cerevisiae to Yarrowia lipolytica was 8:1, and the total amount was 1×10 7CFU / mL), and then fermentation treatment (at 30°C) (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), post-fermentation (anaerobic) for 18 days) was performed. After fermentation, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0029] Example 6 The present example provides a polypeptide-enhanced yellow rice wine brewing method, which is specifically as follows: After 20 kg of waxy rice was cleaned and soaked for 7 hours, it was cooked under normal pressure for 25 minutes (until the rice was soft but not rotten), and then quickly removed and laid to cool at 30°C for standby, to obtain pretreated waxy rice. The pretreated cereal raw material was added with 3.5 kg of yellow rice wine wheat starter for saccharification treatment, and mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (bacterial number ratio of Saccharomyces cerevisiae to Yarrowia lipolytica was 8:1, and the total amount was 1×10 7 CFU / mL), and then fermentation treatment (at 28°C) (main fermentation for 5 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours), post-fermentation (anaerobic) for 10 days) was performed. After fermentation, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0030] Example 7 The present example provides a polypeptide-enhanced yellow rice wine brewing method, which is specifically as follows: After 20 kg of waxy rice was cleaned and soaked for 7 hours, it was cooked under normal pressure for 25 minutes (until the rice was soft but not rotten), and then quickly removed and laid to cool at 30°C for standby, to obtain pretreated waxy rice. The pretreated cereal raw material was added with 3.5 kg of yellow rice wine wheat starter for saccharification treatment, and mixed bacteria liquid of Saccharomyces cerevisiae and Yarrowia lipolytica (bacterial number ratio of Saccharomyces cerevisiae to Yarrowia lipolytica was 8:1, and the total amount was 1×10 7CFU / mL), and then fermentation treatment (28℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation was completed, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0031] Comparative Example 1 The present comparative example provides a brewing method of polypeptide-enhanced yellow rice wine, which is specifically as follows: After 20 kg of waxy rice was cleaned and soaked for 7 hours, it was cooked under normal pressure for 25 minutes (until the rice was soft but not rotten), and then quickly removed and laid to cool at 30℃ for standby, to obtain pretreated waxy rice. The pretreated cereal raw material was added with 3.5 kg of yellow rice wheat starter for saccharification treatment, and the mixed bacteria liquid of saccharomyces cerevisiae and yarrowia lipolytica (the ratio of the number of saccharomyces cerevisiae to yarrowia lipolytica was 8:1, and the total amount was 1×10 7 CFU / mL), and then fermentation treatment (28℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation was completed, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0032] Comparative Example 2 The present comparative example provides a brewing method of polypeptide-enhanced yellow rice wine, which is specifically as follows: After 20 kg of waxy rice was cleaned and soaked for 7 hours, it was cooked under normal pressure for 25 minutes (until the rice was soft but not rotten), and then quickly removed and laid to cool at 30℃ for standby, to obtain pretreated waxy rice. The pretreated cereal raw material was added with 3.5 kg of yellow rice wheat starter for saccharification treatment, and the mixed bacteria liquid of saccharomyces cerevisiae and yarrowia lipolytica (the ratio of the number of saccharomyces cerevisiae to yarrowia lipolytica was 8:1, and the total amount was 1×10 7 CFU / mL), and then fermentation treatment (28℃) was performed (main fermentation for 8 days - intermittent aeration: once every 4 hours for 0-24 hours after feeding, once every 6 hours for 24-48 hours, once every 12 hours for 48-120 hours, and once every 24 hours for 120-192 hours), and post-fermentation (anaerobic) for 18 days. After fermentation was completed, the fermented mash was filtered and squeezed, the obtained filtrate was clarified overnight, and the product yellow rice wine was obtained after decocting.

[0033] The total polypeptide content of the yellow rice wine of Example 1 was 2.8 g / L, which was about 30% higher than that of Comparative Example 1; the total content of sweet amino acids was increased by 18%; the final concentration of erythritol was 6.2 g / L; the bitter taste was low, the taste was soft, and the average sensory score was increased by 20%.

[0034] The concentration of erythritol in the yellow rice wine of Example 2 was up to 8.0 g / L, the total polypeptide content was increased by 28%, the sweet amino acids were increased by 26%, but the alcohol content was decreased by about 5%, and the overall flavor was sweet and low bitter, which was suitable for developing low-alcohol functional yellow rice wine.

[0035] Comparing the yellow rice wine of Comparative Examples 3-5, it was found that the polypeptide yield was the highest (about 2.7 g / L) at 28 ℃, the sweet amino acids were increased by 25%, the erythritol yield was moderate (6.5 g / L), the sensory evaluation was the best, the body of the wine was increased, and the glycol was palatable.

[0036] The total polypeptide content of the yellow rice wine of Example 6 was 2.56 g / L, the total content of sweet amino acids was increased by 15%; the final concentration of erythritol was 4.6 g / L; the bitter taste was low, and the taste was soft.

[0037] The total polypeptide content of the yellow rice wine of Example 7 was 2.9 g / L, the total content of sweet amino acids was increased by about 30%; the final concentration of erythritol was 7.0 g / L; the bitter taste was significantly reduced, the flavor was mellow, and the persistence was strong.

[0038] Table 1 shows the differences in polypeptide content, sweet amino acid content and erythritol content between the yellow rice wine prepared by Example 1, Example 2, Example 4, Example 6 and Example 7 and the yellow rice wine prepared by Comparative Example 1. Specifically as follows: (1) Polypeptide content: high performance liquid chromatography was used for detection, and the total polypeptide content of the Yarrowia lipolytica synergistic fermentation group was increased by about 20-35%, and the small molecule active polypeptide with a molecular weight of 500-1000 Da was significantly increased.

[0039] These small molecule polypeptides were proved to have strong antioxidant capacity and potential immunomodulatory activity.

[0040] (2) Amino acid composition: the content of sweet amino acids (glycine, alanine, serine, threonine, etc.) in the Yarrowia lipolytica synergistic fermentation group was increased by 15-30%, and the relative proportion of bitter amino acids (valine, leucine, phenylalanine, etc.) was reduced by about 10%; the optimization of amino acid spectrum made the bitter taste of the wine body lighter, and the flavor was more soft and harmonious.

[0041] (3) Erythritol production: Yarrowia lipolytica synthesized erythritol during fermentation, and the final concentration was up to 4-8 g / L; the synergistic effect of erythritol and sweet amino acids made the yellow rice wine present a natural sweet taste, rather than the harsh sweet taste brought by added saccharin or sucrose.

[0042] (4) Flavor analysis: The results of electronic tongue and gas chromatography-mass spectrometry analysis showed that the flavor substances of the synergistic fermentation group were more abundant, and formed a "fresh and sweet synergistic effect" with amino acids and polypeptides. Sensory evaluation showed that Example 1, Example 2, Example 4, Example 6 and Example 7 were significantly better than Comparative Example 1 in the three indicators of "sweetness softness", "taste coordination" and "aftertaste persistence".

[0043] Table 1 Comparison of physicochemical indexes of various yellow rice wines In addition, compared with Example 1, although Comparative Example 2 was also inoculated with Yarrowia lipolytica, it did not use intermittent aeration treatment, but was fermented under anaerobic conditions throughout. The results showed that the yield of erythritol in the fermentation broth under this condition was significantly reduced. Yarrowia lipolytica is a strict aerobic or facultative aerobic microorganism, and its growth and erythritol biosynthesis usually depend on a high level of dissolved oxygen. In an anaerobic environment with insufficient dissolved oxygen, its metabolic activity is significantly inhibited, resulting in a significant decrease in erythritol synthesis capacity.

[0044] In contrast, the intermittent aeration strategy used in the present application can periodically provide an appropriate amount of oxygen during the fermentation process, on the one hand to meet the basic growth needs of Yarrowia lipolytica and the normal operation of its erythritol metabolic pathway, and on the other hand to maintain a relatively low-oxygen or anaerobic environment during the aeration interval, which is conducive to the ethanol fermentation of the co-cultured Saccharomyces cerevisiae. Thus, intermittent aeration effectively coordinates the contradiction between the two microorganisms in terms of dissolved oxygen demand, achieving the synergistic growth and metabolic balance of the two in the co-fermentation system, thereby significantly improving the yield of the target product (such as erythritol).

[0045] In summary, the present application realizes a significant increase in the content of polypeptides and optimization of the composition of amino acids by introducing Yarrowia lipolytica with high erythritol production and Saccharomyces cerevisiae for synergistic fermentation in the process of yellow rice wine brewing, and at the same time, the natural improvement of the taste of the wine body by using the metabolic product of Yarrowia lipolytica-erythritol effectively reduces the bitterness of the yellow rice wine. Compared with the prior art, the yellow rice wine provided by the present application not only has a significant improvement in nutritional function, but also improves the flavor characteristics, and does not need to add sweeteners or complex processes, which has strong technical progressiveness and industrial application value.

[0046] The above description of the examples is for the convenience of those of ordinary skill in the art to understand and use the application. Those skilled in the art can easily make various modifications to these examples, and apply the general principles described herein to other examples without having to undergo creative labor. Therefore, the present application is not limited to the above examples, and improvements and modifications made by those skilled in the art without departing from the scope of the present application should be within the scope of protection of the present application.

Claims

1. A method for brewing polypeptide-enhanced rice wine, characterized in that, Includes the following steps: (S1) Add the pretreated grain raw material to wheat koji for saccharification to obtain saccharified material; (S2) Inoculate the saccharified material obtained in step (S1) with yeast fermentation liquid, then carry out fermentation treatment, and post-treatment to obtain polypeptide-enhanced rice wine; The fermentation broth is a mixture of Saccharomyces cerevisiae and Yeast lipolytica; the fermentation includes primary fermentation and secondary fermentation, with the primary fermentation carried out under intermittent aeration and the secondary fermentation carried out under anaerobic conditions.

2. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S1), the grain raw material is rice, or a mixture of rice and soybeans; The rice grains are selected from one or more of glutinous rice, millet, rice, highland barley, or quinoa; The soybeans are selected from one or more of black beans, mung beans, or red beans.

3. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S1), the preprocessing is specifically as follows: The grain raw materials are washed, soaked, and steamed, and then cooled to 28~30℃.

4. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S1), the mass ratio of the grain raw material to the wheat koji is 5~10:

1.

5. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S1), the saccharification process is carried out at a temperature of 28~30 ℃ for 0~48 h.

6. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S2), the ratio of *Saccharomyces cerevisiae* to *Yarrowia lipolyticis* in the fermentation broth is 1:5~10, and the inoculum size is 1×10⁻⁶. 7 CFU / mL; The *Saccharomyces cerevisiae* was the *Saccharomyces cerevisiae* with accession number CGMCC No. 12787, and the *Yersinia lipolytica* was the *Yersinia lipolytica* with accession number ATCC20362.

7. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S2), during the main fermentation process, the pH is 4.0~4.5, the temperature is 28~30 ℃, and the time is 3~8 days.

8. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S2), during the post-fermentation process, the pH is 4.0~4.5, the temperature is 28~30 ℃, and the time is 10~20 days.

9. The brewing method of a polypeptide-enhanced rice wine according to claim 1, characterized in that, In step (S2), the post-processing is specifically as follows: After fermentation, the product is successively pressed, filtered, clarified, and heated.

10. A polypeptide-enhanced rice wine, characterized in that, It is prepared by any one of the methods described in claims 1 to 9.

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