Multi-strain synergistic fermentation process of luzhou-flavor liquor by domestication of ru-china kiln mutant bacterial community

Abstract

The application discloses a liquor multi-strain synergistic fermentation process of Ru porcelain kiln mutation bacteria colony domestication, and belongs to the technical field of liquor brewing. The application collects and domesticates special microorganism colony from the glaze layer of Ru porcelain kiln mutation, separates functional strains with high ester yield, aroma yield and alcohol tolerance, prepares multi-strain synergistic starter, inoculates the base liquor of the light-flavor liquor into the multi-strain synergistic starter, and performs synergistic fermentation under the condition of precisely controlled temperature and humidity. Finally, the product liquor is obtained through distillation and pottery jar storage. The method effectively overcomes the technical problems of single traditional natural fermentation bacteria, insufficient generation of flavor substances and unstable batch quality, significantly enhances the complexity and uniqueness of the liquor flavor, improves the stability of the fermentation process and the consistency of the product, and provides an innovative solution for the production of high-quality light-flavor liquor.

Description

Technical Field

[0001] This invention belongs to the field of liquor fermentation technology, specifically referring to the multi-strain synergistic fermentation process of light-aroma liquor using Ru porcelain kiln-transformed microbial communities. Background Technology

[0002] In the existing light-aroma baijiu brewing technology, the traditional natural fermentation process has long faced many technical bottlenecks. Its microbial community mainly relies on environmental inoculation, which has a single source and unstable structure. This results in insufficient activity of functional strains and low metabolic efficiency during fermentation, limiting the synthesis of flavor substances in the liquor and causing a monotonous aroma lacking complexity. At the same time, the fermentation conditions are poorly controlled, environmental parameters fluctuate greatly, and microbial metabolic pathways are easily disturbed, resulting in inconsistent fermentation processes between different batches of mash. This leads to significant differences in key physicochemical indicators and sensory quality of the raw liquor, resulting in poor product quality stability. In addition, there is a lack of targeted regulation methods for characteristic flavor substances, leading to serious product homogenization and making it difficult to meet the market's demand for high-quality and personalized baijiu, which seriously restricts industrial upgrading and innovative development. Summary of the Invention

[0003] In response to the above situation and to overcome the shortcomings of existing technologies, this invention provides a multi-strain synergistic fermentation process for light-aroma baijiu, which domesticates the kiln-transformed microbial community of Ru porcelain. By domesticating the special microorganisms in the kiln-transformed glaze of Ru porcelain, these microorganisms are introduced into the baijiu fermentation system to construct a synergistic effect of functional microbial communities. Under a controlled environment, they metabolize and produce richer flavor substances, innovatively improving the flavor layers and quality of light-aroma baijiu. This effectively solves the problems of thin flavor layers and large batch quality fluctuations in light-aroma baijiu currently on the market.

[0004] The technical solution adopted in this invention is as follows: This invention proposes a multi-strain synergistic fermentation process for light-aroma baijiu (Chinese liquor) based on the domestication of Ru porcelain kiln-transformation microbial communities, including the following steps: (1) Collection and domestication of microorganisms: Select the kiln-transformed coloration area from the Ru porcelain kiln-transformed fragments for enrichment culture of surface microbial communities, then extract the microbial communities, suspend them in sterile physiological saline, and inoculate them into enrichment culture medium with the extract of light aroma type baijiu mash as the main carbon and nitrogen source. Conduct directional domestication culture for 15-30 days at 28-32℃ and micro-oxygen conditions to obtain domesticated composite kiln-transformed microbial communities; (2) Functional strain isolation and expansion: The composite microbial community after domestication in step (1) is plate isolated, and at least three functional strains with high ester production, aroma production or tolerance to high alcohol concentration are screened out respectively. The functional strains include, but are not limited to, yeast, Bacillus and Mucor. Each functional strain is expanded to the logarithmic growth phase in liquid seed culture medium to obtain functional strain seed liquid. (3) Multi-strain synergistic fermentation: High-quality sorghum, wheat, and peas are used as raw materials, and the base mash for light-aroma baijiu is prepared by steaming, distilling, and fermentation in earthen vats; the seed liquids of various functional strains prepared in step (2) are mixed in a preset ratio to form a multi-strain synergistic fermentation agent, wherein the ratio of viable bacteria of yeast, ester-producing Bacillus, and Mucor is (5-8):(1-3):(0.5-1.5); the synergistic fermentation agent is evenly inoculated into the base mash, and the inoculation amount is 1%-3% of the total mass of the mash; (4) Temperature and humidity controlled fermentation: After inoculation, the mash is transferred to a fermentation container that can precisely control the temperature and humidity. Co-fermentation is carried out for 25-40 days at 18-25℃ and 75%-85% relative humidity. During the first 10 days of fermentation, the temperature is gradually increased by 0.5-1℃ per day, and then kept constant in the later stage. (5) Post-fermentation treatment: After fermentation, the mash is taken out and distilled and the liquor is extracted by quality. The resulting liquor is stored in earthenware jars to age and mature, and then the finished liquor is obtained.

[0005] Further, the composition of the enrichment culture medium in step (1) is: 200-400 mL / L of light-aroma baijiu mash extract, 5-15 g / L of glucose, 1-3 g / L of potassium dihydrogen phosphate, 0.5-1.5 g / L of magnesium sulfate, and natural pH; the micro-oxygen condition refers to the oxygen volume concentration above the culture medium being maintained at 5%-10%.

[0006] Furthermore, the functional strains screened in step (2) include: a brewing yeast that can grow and metabolize normally at a 12% vol alcohol concentration, a Bacillus that can metabolize and produce aromatic main esters such as ethyl acetate and ethyl lactate, and a Mucor that can produce complex aroma substances such as terpenes and pyrazines.

[0007] Furthermore, the preparation of the multi-strain synergistic fermentation agent in step (3) also includes culturing the seed liquids of each functional strain in a culture medium containing 5%-8% vol of light-aroma baijiu base liquor for 12-24 hours to improve their ethanol tolerance before mixing.

[0008] Furthermore, the total viable count of the multi-strain synergistic fermentation agent is not less than 1×10⁸ CFU / mL, and the agent is stored at 4°C using a special preservative containing 5%-8% vol of light-aroma baijiu base liquor.

[0009] Furthermore, in step (3), the preparation of the basic mash is carried out with the following raw material ratio: 70-80% sorghum, 15-20% wheat, and 5-10% peas. After the raw materials are steamed, the amount of Daqu used is 18-25% of the total mass of the raw materials. The fermentation temperature in the vat is 18-22℃, and the initial fermentation period is 7-12 days.

[0010] Further, the fermentation container in step (4) is a ceramic jar or stainless steel can with Ru porcelain kiln transformation fragment powder or imitation Ru porcelain glaze coating attached to the inner wall, and the amount of powder or coating attached is 30-70% of the inner wall surface area.

[0011] Furthermore, during the fermentation process described in step (4), the mash is turned over every 5-7 days, and a nutrient solution containing trace metal elements is added. The nutrient solution contains zinc ions and manganese ions, both at a concentration of 0.01-0.05 mmol / L.

[0012] Furthermore, its total ester content is not less than 3.5 g / L, the ratio of ethyl acetate to ethyl lactate is (1.2-1.8):1, and the content of characteristic terpenoids and pyrazines produced by the metabolism of Ru porcelain kiln-transformed bacteria in its aroma components is more than 20% higher than that of traditional light-aroma baijiu.

[0013] Furthermore, during the storage of the liquor in earthenware jars, the inner wall of the jar is preferably made of a Ru porcelain-like material with a microporous structure to simulate the Ru porcelain environment and promote the aging of the liquor and the fusion of flavors.

[0014] The beneficial effects achieved by this invention are as follows: This scheme proposes a multi-strain co-fermentation process for light-aroma baijiu, which incorporates domesticated Ru porcelain kiln-transformed microbial communities. By introducing domesticated Ru porcelain kiln-transformed microbial communities, the process complements the traditional baijiu fermentation system. During co-fermentation, the introduced microbial communities can metabolize and produce a series of characteristic flavor compounds that are not present or are produced in low quantities by traditional light-aroma baijiu brewing microbial systems, such as specific terpenes and pyrazines. This process substantially expands the aroma molecular spectrum of the baijiu, increasing the layers, fullness, and unique quality of the flavor while maintaining the main light-aroma style.

[0015] By employing multi-strain inoculation based on the characteristics of functional strains and precise control of the fermentation environment, this process successfully constructs a more regulated microbial ecosystem. The combination of specific functional strains inhibits the excessive growth of miscellaneous bacteria, while the inner wall of the fermentation container made of Ru porcelain and the step-by-step temperature control strategy create an advantageous growth and metabolic environment for the target microbial community, reducing batch flavor fluctuations common in traditional natural fermentation and improving the predictability of the fermentation process and the stability of the final product quality. Attached Figure Description

[0016] Figure 1 This invention relates to a light-aroma baijiu (Chinese liquor) domesticated with Ru porcelain kiln-transformed microorganisms. Figure 2 This invention relates to a light-aroma baijiu (Chinese liquor) domesticated with Ru porcelain kiln-transformed microorganisms. The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0018] It should be noted that, unless otherwise specified, all chemical reagents involved in this invention were purchased through commercial channels.

[0019] Example 1 A multi-strain synergistic fermentation process for light-aroma baijiu, domesticated with Ru porcelain kiln-transformed microbial communities. The preparation process includes microbial collection and domestication: kiln-transformed coloration areas are selected from Ru porcelain kiln-transformed fragments for enrichment and culture of surface microbial communities. These microbial communities are then extracted, suspended in sterile physiological saline, and inoculated into an enrichment medium with a light-aroma baijiu mash extract as the main carbon and nitrogen source. The enrichment medium consists of 200 mL / L mash extract, 5 g / L glucose, 1 g / L potassium dihydrogen phosphate, and 0.5 g / L magnesium sulfate. The microorganisms were acclimated to a compound kiln-fermentation microbial community after 15 days of directed domestication at 28℃ and 5% oxygen concentration. Functional strains were then isolated and expanded: the compound microorganisms were plate-separated, and at least three functional strains with high ester production, aroma production, or tolerance to high alcohol concentrations were screened. These included a brewing yeast that could grow and metabolize normally at 12% vol alcohol concentration, a Bacillus that could metabolize and produce ethyl acetate, ethyl lactate, and other main aroma-type esters, and a Mucor that could produce complex aroma substances such as terpenes and pyrazines. Each functional strain was expanded to the logarithmic growth phase in liquid seed culture medium to prepare functional strain seed liquids. Before mixing, each functional strain seed liquid was cultured separately in a medium containing 5% vol light-aroma baijiu base liquor for 12 hours to adapt to ethanol tolerance. Then, multi-strain co-fermentation was carried out: high-quality sorghum, wheat, and peas were used as raw materials, with a ratio of 70% sorghum, 15% wheat, and 5% peas, and the mixture was steamed. The base mash for light-aroma baijiu was prepared by distillation and fermentation in earthen vats, with the amount of daqu (fermentation starter) accounting for 18% of the total raw material mass. The fermentation temperature in the vats was 18℃, and the initial fermentation period was 7 days. The prepared seed liquids of various functional strains were mixed according to a predetermined ratio to form a multi-strain synergistic fermentation agent, in which the live count ratio of yeast, ester-producing Bacillus, and Mucor was 5:1:0.5. The synergistic fermentation agent was evenly inoculated into the base mash at an inoculation amount of 1% of the total mash mass. Subsequently, temperature and humidity controlled fermentation was carried out: the inoculated mash was transferred... The mash is placed in a precisely temperature- and humidity-controlled fermentation container. The inner wall of the container is coated with Ru porcelain kiln-transformation fragments or a Ru porcelain glaze coating, covering 30% of the inner wall surface area. Co-fermentation is carried out for 25 days at 18℃ and 75% relative humidity. During the first 10 days of fermentation, the temperature is gradually increased by 0.5℃ per day, and then kept constant. During fermentation, the mash is turned every 5 days, and a nutrient solution containing trace metal elements, including zinc and manganese ions, is added at a concentration of 0.01 mmol / L. Finally, post-fermentation processing is carried out: after fermentation, the mash is removed, distilled, and the resulting spirit is aged in earthenware jars to obtain the finished spirit. The finished spirit has a total ester content of not less than 3.5 g / L, an ethyl acetate to ethyl lactate ratio of 1.2:1, and its aroma components show that the content of characteristic terpenoids and pyrazines produced by the metabolism of Ru porcelain kiln-transformation bacteria is more than 20% higher than that of traditional light-aroma baijiu.

[0020] During the storage of the baijiu in earthenware jars, the inner wall of the jar is preferably made of imitation Ru porcelain material with a microporous structure to simulate the Ru porcelain environment, promote the aging of the liquor and the integration of flavors; a multi-strain synergistic fermentation agent for this process is a liquid mixed agent containing domesticated Ru porcelain kiln-transformation yeast, ester-producing Bacillus, and aroma-producing Mucor, with the viable cell ratio of each strain being 5:1:0.5, and the total viable cell count not less than 1×108 CFU / mL, and the agent is stored at a low temperature of 4℃ using a special protective agent containing 5% vol of light-aroma baijiu base liquor.

[0021] Example 2 A multi-strain synergistic fermentation process for light-aroma baijiu, domesticated with Ru porcelain kiln-transformed microbial communities. The preparation process includes microbial collection and domestication: kiln-transformed coloration areas are selected from Ru porcelain kiln-transformed fragments for enrichment and culture of surface microbial communities. These microbial communities are then extracted, suspended in sterile physiological saline, and inoculated into an enrichment medium with a light-aroma baijiu mash extract as the main carbon and nitrogen source. The enrichment medium consists of 300 mL / L mash extract, 10 g / L glucose, 2 g / L potassium dihydrogen phosphate, and 1.0 g / L magnesium sulfate. The culture was carried out at g / L for 23 days under microaerobic conditions (7.5% oxygen concentration) at 30℃ to obtain a domesticated composite kiln-fermentation microbial community. Functional strains were then isolated and expanded: the domesticated composite microbial community was plate-separated, and at least three functional strains with high ester production, aroma production, or tolerance to high alcohol concentrations were screened. These included a brewer's yeast that could grow and metabolize normally at 12% vol alcohol concentration, a Bacillus strain that could metabolize and produce aromatic main esters such as ethyl acetate and ethyl lactate, and a strain that could produce terpenes and pyrimidines. Mucor, a fungus containing complex aroma compounds such as azinides, was used to prepare functional strains. Each strain was cultured separately in liquid seed culture medium to the logarithmic growth phase to obtain functional strain seed liquids. Before mixing, each functional strain seed liquid was cultured separately in a medium containing 7% vol of light-aroma baijiu base liquor for 18 hours to test its ethanol tolerance. Then, multi-strain co-fermentation was carried out: using high-quality sorghum, wheat, and peas as raw materials, with a ratio of 75% sorghum, 18% wheat, and 7% peas, the base mash for light-aroma baijiu was prepared through steaming, distillation, and fermentation in earthen vats. The amount of Daqu (a type of starter culture) used was 2% of the total mass of the raw materials. 2%, fermentation temperature in the fermentation tank is 20℃, and the initial fermentation period is 10 days; the prepared seed liquids of various functional strains are mixed according to a preset ratio to form a multi-strain synergistic fermentation agent, in which the live count ratio of yeast, ester-producing Bacillus, and Mucor is 6.5:2:1; the synergistic fermentation agent is evenly inoculated into the base mash, with an inoculation amount of 2% of the total mass of the mash; then temperature and humidity controlled fermentation is carried out: the inoculated mash is transferred into a fermentation container that can precisely control temperature and humidity. The inner wall of the fermentation container is coated with Ru porcelain kiln transformation fragment powder or imitation Ru porcelain glaze coating, with the coating amount covering 50% of the inner wall surface area. The mash was fermented for 33 days at 22℃ and 80% relative humidity. For the first 10 days, the temperature was gradually increased by 0.8℃ per day, and then kept constant. During fermentation, the mash was turned every 6 days, and a nutrient solution containing trace metal elements (zinc and manganese ions, each at a concentration of 0.03 mmol / L) was added. Finally, post-fermentation processing was carried out: after fermentation, the mash was removed, distilled, and the resulting spirit was aged in earthenware jars to obtain the finished spirit. The finished spirit has a total ester content of no less than 3.5 g / L, an ethyl acetate to ethyl lactate ratio of 1.5:1, and its aroma components show that the content of characteristic terpenoids and pyrazines produced by the metabolism of Ru porcelain kiln-transformed microorganisms is more than 20% higher than that of traditional light-aroma baijiu.

[0022] During the storage of the baijiu in earthenware jars, the inner wall of the jar is preferably made of imitation Ru porcelain material with a microporous structure to simulate the Ru porcelain environment, promote the aging of the baijiu and the integration of flavors; a multi-strain synergistic fermentation agent for this process is a liquid mixed agent containing domesticated Ru porcelain kiln transformation yeast, ester-producing Bacillus, and aroma mold, with the ratio of viable bacteria of each strain being 6.5:2:1, and the total viable bacteria count being not less than 1×108 CFU / mL, and the agent is stored at a low temperature of 4℃ using a special protective agent containing 7% vol of light aroma baijiu base liquor.

[0023] Example 3 A multi-strain synergistic fermentation process for light-aroma baijiu, domesticated with Ru porcelain kiln-transformed microbial communities. The preparation process includes strain collection and domestication: Microbial communities from kiln-transformed areas of Ru porcelain fragments are enriched and cultured, then extracted and suspended in sterile physiological saline. These communities are then inoculated into an enrichment medium with a mash extract of light-aroma baijiu as the main carbon and nitrogen source. The enrichment medium consists of 400 mL / L mash extract, 15 g / L glucose, 3 g / L potassium dihydrogen phosphate, and 1.5 g / L magnesium sulfate. A 30-day directed domestication culture is conducted at 32℃ under microaerobic conditions (10% oxygen concentration) to obtain a domesticated composite kiln-transformed microbial community. Next, functional strains are isolated and expanded: The domesticated composite microbial community is plate-separated, and at least three functional strains with high ester production, aroma production, or tolerance to high alcohol concentrations are screened. These include one brewing yeast strain capable of normal growth and metabolism at 12% vol alcohol concentration, and one strain capable of producing ethyl acetate, ethyl lactate, and other main light-aroma esters. Bacillus and a strain of Mucor that produces complex aroma compounds such as terpenes and pyrazines were selected. Each functional strain was cultured separately in liquid seed culture medium to the logarithmic growth phase to obtain functional strain seed liquids. Before mixing, each functional strain seed liquid was subjected to ethanol tolerance culture for 24 hours in a medium containing 8% vol light-aroma baijiu base liquor. Then, multi-strain co-fermentation was carried out: using high-quality sorghum, wheat, and peas as raw materials, in a ratio of 80% sorghum, 20% wheat, and 10% peas, after cleaning... The base mash for light-aroma baijiu was prepared by steaming, distilling, and fermenting in earthen vats. The amount of daqu (a type of starter culture) used was 25% of the total raw material mass. The fermentation temperature was 22℃, and the initial fermentation period was 12 days. Seed liquids of various functional bacterial strains were mixed according to a predetermined ratio to form a multi-strain synergistic fermentation agent, with a live bacteria ratio of yeast, ester-producing Bacillus, and *Mucor* at 8:3:1.5. The synergistic fermentation agent was evenly inoculated into the base mash at a rate of 3% of the total mash mass. Subsequently, temperature and humidity controlled fermentation was carried out. The inoculated mash was then... The mash was transferred to a fermentation container with precise temperature and humidity control. The inner wall of this container was coated with powdered fragments of Ru ware kiln-transformed porcelain or a coating of imitation Ru ware glaze, covering 70% of the inner wall surface area. Co-fermentation was carried out for 40 days at 25°C and 85% relative humidity. For the first 10 days of fermentation, the temperature was gradually increased by 1°C per day, and then maintained at a constant temperature. During fermentation, the mash was turned every 7 days, and a nutrient solution containing trace metal elements, including zinc and manganese ions at a concentration of 0.05%, was added. mmol / L; Finally, post-fermentation treatment is carried out: After fermentation, the mash is taken out, distilled, and the liquor is extracted by quality and quantity. The resulting raw liquor is stored in earthenware jars for aging to obtain the finished liquor. The total ester content of the finished liquor is not less than 3.5 g / L, the ratio of ethyl acetate to ethyl lactate is 1.8:1, and the content of characteristic terpenoids and pyrazines produced by the metabolism of Ru porcelain kiln-transformed bacteria in its aroma components is more than 20% higher than that of traditional light aroma baijiu.

[0024] During the storage of the baijiu in earthenware jars, the inner wall of the jar is preferably made of imitation Ru porcelain material with a microporous structure to simulate the Ru porcelain environment, promote the aging of the liquor and the integration of flavors; a multi-strain synergistic fermentation agent for this process is a liquid mixed agent containing domesticated Ru porcelain kiln transformation yeast, ester-producing Bacillus, and aroma mold, with the viable count ratio of each strain being 8:3:1.5, and the total viable count being not less than 1×108 CFU / mL, and the agent is stored at a low temperature of 4℃ using a special protective agent containing 8% vol of light aroma baijiu base liquor.

[0025] Comparative Example 1: The specific implementation method is the same as in Example 1, except that: the complex microbial community collected and domesticated from the Ru porcelain kiln transformation fragments is not used, nor is a multi-strain synergistic fermentation agent prepared; during the fermentation stage, only the light-aroma baijiu base mash with the same raw materials, dosage and preparation method as in Example 1 is used, and the fermentation relies entirely on the naturally existing microbial community in the daqu, and traditional solid-state fermentation is carried out under the same fermentation container, temperature and humidity conditions; the resulting mash is processed by the same distillation and storage process to obtain the finished liquor.

[0026] Experimental Example 1: The experimental procedure first involved precisely preparing mash samples for both the experimental and control groups. The experimental group was prepared according to the process parameters of the three embodiments, and the process flow is as follows: Figure 1 As shown in the figure; the control group was conducted in a comparative proportion, with three parallel replicates in each group, and initial fermentation parameters were recorded; subsequently, approximately 200 g of mash samples and 50 mL of headspace gas samples were dynamically collected on days 0, 7, 15, 25, 33, and 40 of fermentation for subsequent analysis; then, high-throughput sequencing was used to analyze microbial community diversity, and physicochemical indicators such as mash acidity, pH, starch content, reducing sugar content, and alcohol concentration were monitored; gas chromatography-mass spectrometry was used to comprehensively analyze volatile flavor compounds such as esters, terpenes, and pyrazines, and a professional sensory evaluation team conducted blind tasting evaluations; finally, statistical software was used to conduct difference tests, consistency analyses, and correlation analyses on microbial diversity indices, key physicochemical indicators, characteristic flavor compound content, and sensory score data to systematically evaluate fermentation stability and product flavor uniqueness.

[0027] The results of the experiment comparing the traditional natural fermentation process with the multi-strain synergistic fermentation process of Ru porcelain kiln-transformation microbial communities are shown in Table 1. Figure 2As shown, the experimental group significantly outperformed the control group in terms of microbial community richness, alcohol yield, ester synthesis capacity, increase in characteristic flavor compounds, and batch consistency. This result demonstrates that by introducing domesticated kiln-transformed microorganisms and optimizing process parameters, the fermentation system can drive metabolic pathways more efficiently and stably, achieving enhanced flavor diversity and product uniformity within a relatively shorter or moderate fermentation cycle. In particular, the optimized conditions, exemplified by Example 2, exhibited the best synergistic effect, promoting the generation of complex aroma compounds while effectively controlling fermentation fluctuations. This reflects the dual core effects of the innovative process in substantially enhancing the flavor profile and uniqueness of light-aroma baijiu, while simultaneously strengthening the controllability of the production process and the stability of product quality, providing empirical evidence for the innovation of traditional brewing techniques.

[0028] Table 1. Effects of different fermentation processes on key indicators of light-aroma baijiu ; It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0030] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A multi-strain synergistic fermentation process for light-aroma baijiu, characterized by the domestication of Ru porcelain kiln-transformed microbial communities. Includes the following steps: (1) Collection and domestication of microorganisms: Select the kiln-transformed coloration area from the Ru porcelain kiln-transformed fragments for enrichment culture of surface microbial communities, then extract the microbial communities, suspend them in sterile physiological saline, and inoculate them into enrichment culture medium with the extract of light aroma type baijiu mash as the main carbon and nitrogen source. Conduct directional domestication culture for 15-30 days at 28-32℃ and micro-oxygen conditions to obtain domesticated composite kiln-transformed microbial communities; (2) Functional strain isolation and expansion: The composite microbial community after domestication in step (1) is plate isolated, and at least three functional strains with high ester production, aroma production or tolerance to high alcohol concentration are screened out respectively. The functional strains include, but are not limited to, yeast, Bacillus and Mucor. Each functional strain is expanded to the logarithmic growth phase in liquid seed culture medium to obtain functional strain seed liquid. (3) Multi-strain synergistic fermentation: Using high-quality sorghum, wheat, and peas as raw materials, a light-aroma baijiu base mash is prepared through steaming, distillation, and fermentation in earthen vats; the seed liquids of various functional strains prepared in step (2) are mixed in a preset ratio to form a multi-strain synergistic fermentation agent, wherein the ratio of viable bacteria of yeast, ester-producing Bacillus, and Mucor is (5-8):(1-3):(0.5-1.5); the synergistic fermentation agent is evenly inoculated into the base mash, with an inoculation amount of 1%-3% of the total mass of the mash; (4) Temperature and humidity controlled fermentation: After inoculation, the mash is transferred to a fermentation container that can precisely control the temperature and humidity. Co-fermentation is carried out for 25-40 days at 18-25℃ and 75%-85% relative humidity. During the first 10 days of fermentation, the temperature is gradually increased by 0.5-1℃ per day, and then kept constant in the later stage. (5) Post-fermentation treatment: After fermentation, the mash is taken out and distilled and the liquor is extracted by quality. The resulting liquor is stored in earthenware jars to age and mature, and then the finished liquor is obtained.

2. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 1, characterized in that: The enrichment culture medium in step (1) consists of: 200-400 mL / L of light-aroma baijiu mash extract, 5-15 g / L of glucose, 1-3 g / L of potassium dihydrogen phosphate, 0.5-1.5 g / L of magnesium sulfate, and natural pH; the micro-oxygen conditions refer to the oxygen volume concentration above the culture medium being maintained at 5%-10%.

3. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 2, characterized in that: The functional strains screened in step (2) include: a brewing yeast that can grow and metabolize normally at a 12% vol alcohol concentration, a Bacillus that can metabolize and produce aromatic main esters such as ethyl acetate and ethyl lactate, and a Mucor that can produce complex aroma substances such as terpenes and pyrazines.

4. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 3, characterized in that: The preparation of the multi-strain synergistic fermentation agent in step (3) also includes culturing the seed liquids of each functional strain in a culture medium containing 5%-8% vol of light-aroma baijiu base liquor for 12-24 hours to improve their ethanol tolerance.

5. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 4, characterized in that: The total viable count of the multi-strain synergistic fermentation agent is not less than 1×10⁻⁶. 8 The bacterial agent is CFU / mL and is stored at 4℃ using a special preservative containing 5%-8% vol of light-aroma baijiu base liquor.

6. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 5, characterized in that: The preparation of the basic mash in step (3) involves a raw material ratio of 70-80% sorghum, 15-20% wheat, and 5-10% peas. After steaming, the amount of Daqu (a type of starter culture) used is 18-25% of the total mass of the raw materials. The fermentation temperature in the vat is 18-22℃, and the initial fermentation period is 7-12 days.

7. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 6, characterized in that: The fermentation container mentioned in step (4) is a ceramic jar or stainless steel can with Ru porcelain kiln transformation fragment powder or imitation Ru porcelain glaze coating attached to the inner wall. The amount of powder or coating attached is 30-70% of the inner wall surface area.

8. The multi-strain synergistic fermentation process for light-aroma baijiu based on the Ru porcelain kiln-transformation microbial community domestication according to claim 7, characterized in that: In step (4), the fermentation process is carried out every 5-7 days, and a nutrient solution containing trace metal elements is added. The nutrient solution contains zinc ions and manganese ions, with a concentration of 0.01-0.05 mmol / L.

9. A light-aroma baijiu prepared by the process according to any one of claims 1-8, characterized in that: Its total ester content is not less than 3.5 g / L, the ratio of ethyl acetate to ethyl lactate is (1.2-1.8):1, and the content of characteristic terpenoids and pyrazines produced by the metabolism of Ru porcelain kiln-transformed bacteria in its aroma components is more than 20% higher than that of traditional light aroma baijiu.

10. The light-aroma baijiu acclimated with Ru porcelain kiln-transformed microorganisms according to claim 9, characterized in that: During the storage of the liquor in earthenware jars, the inner wall of the jar is preferably made of imitation Ru porcelain material with a microporous structure to simulate the Ru porcelain environment and promote the aging of the liquor and the integration of flavors.

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