Special distiller's yeast for tea wine and preparation method thereof

Abstract

The invention belongs to the technical field of distiller's yeast preparation, and particularly relates to special distiller's yeast for tea wine and a preparation method thereof. The preparation method comprises the following steps: S1, raw material preparation: taking 4-8 parts of barley, 85-95 parts of wheat and 2-5 parts of tea leaves, uniformly mixing, crushing, and adjusting the water content to 50-70% to obtain a starter propagation raw material; s2, blank making: making the starter making raw materials into starter blanks; s3, culturing the koji blank, namely culturing the koji blank under the condition of 18-25 DEG C until the temperature of the koji blank is constant; and S4, secondary fermentation: raising the temperature to 40-50 DEG C, and carrying out secondary fermentation on the koji blank until the water content of the koji blank is reduced to 12-15%, so as to obtain the special distiller's yeast for tea wine. The tea wine brewed by using the special distiller's yeast for the tea wine as a saccharification leavening agent is mellow in flavor, tea aroma and wine aroma are fused and revealed, and unique tea wine quality is formed.

Description

Technical Field

[0001] The invention belongs to the technical field of koji preparation, and particularly relates to a special koji for tea wine and a preparation method thereof. Background Art

[0002] In the traditional sense, tea wine refers to a type of drinking wine that uses tea leaves as the main raw material and is made through direct extraction, preparation or biological fermentation to have the fragrance of tea and the mellowness of wine. It has the characteristics of both tea and wine and is a low-alcohol, low-sugar beverage wine that integrates nutrition and health care. The development of tea wine has gone through a process from the initial immersion method, to the aroma distillation blending method, and then to the natural fermentation distillation method, with the degree of refinement and targeting becoming increasingly higher.

[0003] However, the fermented tea wines in the existing patent library mostly use traditional koji as the fermentation agent, such as patent applications CN115074197A, CN113583784A, etc. Invention patent CN113322143B ferments sorghum grains by using pure black tea containing Eurotium cristatum as raw material and fortified strains to make koji, so that the mash produces tea-flavored substances during the fermentation process, but in this patent, the fermentation cycle of the wine is 60 days. In patent application 2023116708090, the applicant requested protection for a tea-flavor and wine-flavor composite low-intoxication tea wine, which also uses traditional Daqu as a fermentation agent during the brewing process, and the fermentation cycle is 60-90 days.

[0004] In general, the current fermentation cycle of fermented tea wine is too long, which is not conducive to cost control. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a special koji for tea wine, so as to achieve the effect of shortening the fermentation period of tea wine preparation. The tea wine referred to in the present invention is a tea-flavored liquor with the characteristics of tea and wine and a unique flavor, which is made from five kinds of grains such as sorghum, rice, glutinous rice, wheat, corn and tea leaves as main raw materials and is produced through biological fermentation.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A method for preparing special distiller's yeast for tea wine comprises the following steps:

[0008] S1. Raw material preparation: by weight, take 4-8 parts of barley, 85-95 parts of wheat and 2-5 parts of tea, mix well and crush, and adjust the moisture content to 50-70% to obtain koji raw materials;

[0009] S2. Billet making: making the koji raw materials into koji billets;

[0010] S3. Cultivating the koji blank: culturing the koji blank at 18-25° C. until the temperature of the koji blank is constant;

[0011] S4. Secondary fermentation: The temperature is raised to 40-50°C to perform secondary fermentation on the koji, and the water content of the koji is fermented to 12-15%, thereby obtaining the special koji for tea wine.

[0012] In certain embodiments, in S1, the tea leaves include at least two of green tea, oolong tea, black tea, white tea, dark tea or yellow tea.

[0013] In certain embodiments, in S1, the fineness of the koji-making raw material is 50-80 mesh.

[0014] In certain embodiments, in S2, the size of the billet is 20-30 cm×15-20 cm×10-15 cm.

[0015] In certain embodiments, in S2, the method for making the curved blank is mechanical pressing or manual pressing.

[0016] The present invention also provides a special distiller's yeast for tea wine obtained by the above-mentioned preparation method.

[0017] The present invention also provides application of the above-mentioned special koji for tea wine in brewing tea wine.

[0018] In certain embodiments, the application includes using the tea wine special koji as a fermentation agent to prepare a tea wine with a composite tea aroma and wine aroma, and the preparation method of the tea wine with a composite tea aroma and wine aroma includes the following steps:

[0019] Select high-quality grain raw materials, and carry out the steps of washing, soaking, steaming and saccharification in sequence to obtain grain waste;

[0020] Adding the tea wine special distiller's yeast to the grain dregs, sealing and fermenting for 40-50 days to obtain dregs;

[0021] Adding mixed tea leaves to the fermented grains under aseptic conditions and stirring evenly, and then continuing fermentation under the same conditions for 3-7 days;

[0022] After fermentation is complete, the wine is distilled.

[0023] In certain embodiments, the amount of the tea wine yeast added is 15-25% of the mass of the grain dregs.

[0024] In certain embodiments, the mixed tea leaves are obtained by uniformly mixing yellow tea, black tea, red tea and white tea in a mass ratio of 10-20:1-10:2-12:2-10.

[0025] It should be noted that although the population and number of microorganisms attached to the surface of grains will change with the change of seasons and temperature, the applicant has found in previous studies that even if the koji-making raw materials are prepared with wheat, barley and tea leaves in different seasons or under different temperature conditions, the tea wine special koji prepared by the method of the present invention has the same final quality, such as microbial species, quantity, fermentation capacity, total acid and total ester content, etc., that is, the initial state of the raw materials does not affect the quality of the final koji. Therefore, the tea wine special koji of the present invention does not need to add any external bacterial agent to regulate the microbial species during preparation.

[0026] The applicant speculates that this is because: some saccharifying bacteria or fermentation bacteria naturally present in grains have a competitive advantage over other microorganisms during the cultivation process of the koji, and the tea leaves added to the raw materials contain a large amount of phenolic substances, which have an antagonistic effect on some miscellaneous bacteria. Therefore, as the cultivation time continues, these dominant strains gradually expand and reach a balance, while other microorganisms gradually die out. Although the initial number of these dominant microorganisms may be different in different seasons or climates, the final competition results are the same under the cultivation conditions of the present invention. Therefore, the koji exhibits the same physical and chemical indicators.

[0027] The cultivation of the koji blank in the present invention mainly includes two stages. In the first stage, the cultivation temperature is relatively low, and the microorganisms mainly perform aerobic respiration and consume oxygen in the koji blank. After the oxygen is exhausted, the temperature of the koji blank no longer changes significantly. At this time, the second stage of cultivation is entered, the temperature of the koji blank is increased, and the microorganisms perform secondary fermentation. This stage mainly performs anaerobic fermentation. As the temperature gradually increases, the moisture content of the koji blank gradually decreases over time until it reaches a certain limit, and then the fermentation is terminated to obtain the koji.

[0028] It should be noted that in the present invention, the dosage ratio of barley, wheat and the tea leaves needs to be strictly limited. Since the density of tea leaves themselves is lower than that of barley or wheat, if the amount of tea leaves is too much, it will be difficult to make the koji blank, which is specifically manifested as difficulty in compacting and compacting the koji blank. If the amount of tea leaves is too little, the porosity of the koji blank is insufficient and the oxygen content is low, which affects the cultivation and fermentation of the koji blank.

[0029] The beneficial effects of the present invention are:

[0030] 1. The present invention provides a special koji for tea wine, which is used as a saccharifying and fermenting agent to brew tea wine, realizing a major change and innovation in koji, and is a breakthrough achievement in special koji for brewing wine, especially realizing the production of tea wine and forming a unique tea-flavored liquor quality, which has significant innovation and application value.

[0031] 2. Using the tea wine special distiller's yeast of the present invention as a saccharification and fermentation agent to brew tea wine can effectively shorten the fermentation period. Compared with tea wine fermented with traditional Daqu, the aroma activity values ​​such as ethyl isovalerate and ethyl caproate are higher, while the activity values ​​of dimethyl trisulfide with fishy smell are lower. The flavor is mellower, and the tea aroma and wine aroma are more integrated and revealed, forming a unique tea wine quality. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further described in detail below in conjunction with Example 1, but the protection scope of the present invention is not limited to the following.

[0033] Example 1

[0034] Prepare a special koji for tea wine according to the following steps:

[0035] S1. Raw material preparation: Take 6 parts of barley, 90 parts of wheat and 5 parts of mixed tea (wherein the mixed tea consists of 1 part of green tea, 2 parts of black tea, 1 part of white tea and 1 part of dark tea) by weight, mix all the raw materials evenly and grind them to a fineness of 60 mesh, then add water to adjust the moisture content to 60% to obtain the koji raw material;

[0036] S2. Billet making: The koji raw materials are placed into a koji basket, and a koji billet of 20 cm (length) × 15 cm (width) × 10 cm (height) is formed by manual koji pressing;

[0037] S3. Cultivation of koji billets: Cultivate the koji billets at 20° C. and monitor the temperature at any time until the temperature of the koji billets no longer changes.

[0038] S4. Secondary fermentation: The ambient temperature of the koji is raised to 45°C for secondary fermentation. During the secondary fermentation, the moisture content of the koji decreases continuously until it drops to 14%. At this time, the fermentation is terminated to obtain the special koji for tea wine.

[0039] Example 2

[0040] Prepare a special koji for tea wine according to the following steps:

[0041] S1. Raw material preparation: by weight, take 8 parts of barley, 85 parts of wheat and 3 parts of mixed tea (wherein the mixed tea consists of 1 part of green tea, 1 part of black tea and 1 part of oolong tea), mix all the raw materials evenly and grind them to a fineness of 60 mesh, then add water to adjust the moisture content to 60% to obtain koji raw materials;

[0042] S2. Billet making: The koji raw material is made into a koji billet of 25 cm (length) × 20 cm (width) × 10 cm (height) by mechanical koji making;

[0043] S3. Cultivating the koji billet: culturing the koji billet at 22° C. and monitoring the temperature at any time until the temperature of the koji billet does not change;

[0044] S4. Secondary fermentation: The ambient temperature of the koji is raised to 50°C for secondary fermentation until the moisture content of the koji gradually decreases to 14%, and the fermentation is terminated to obtain the koji for tea wine.

[0045] Comparative Example 1

[0046] A distiller's yeast was prepared, which differed from Example 1 in that, in S1, the ratios of the raw materials were different. Specifically, the raw materials of Comparative Example 1 were 6 parts of barley, 75 parts of wheat and 20 parts of mixed tea (wherein the mixed tea consisted of 5 parts of green tea, 5 parts of black tea, 5 parts of white tea and 5 parts of dark tea).

[0047] Comparative Example 2

[0048] A distiller's yeast is prepared. The difference from Example 1 is that in S1, the ratio of each raw material is different. Specifically, the raw materials of Comparative Example 2 are 10 parts of barley, 90 parts of wheat and 1 part of mixed tea (wherein the mixed tea consists of 0.25 parts of green tea, 0.25 parts of black tea, 0.25 parts of white tea and 0.25 parts of dark tea).

[0049] Comparative Example 3

[0050] A distiller's yeast is prepared, which differs from Example 1 in that after S3 is completed, the distiller's yeast is air-dried at room temperature until the moisture content is 14%.

[0051] Comparative Example 4

[0052] A distiller's yeast is prepared, which differs from Example 1 in that, after S2 is completed, the koji is cultured at 40° C. until its moisture content reaches 14%.

[0053] Quality evaluation of wine yeast:

[0054] The yeast count and mold count of the distiller's yeast prepared in the above example were determined with reference to GB / T 4789.15-2016, the total acid content was determined with reference to GB12456-2021, the total ester content was determined with reference to GB / T 10345-2022, the pH value was determined with reference to NY / T 525-2021, the theanine content was determined with reference to GB / T 23193-2017, and the tea polyphenol content was determined with reference to GB / T 8313-2018. The measurement results are shown in Table 1 below.

[0055] Table 1

[0056]

[0057]

[0058] Comparing Example 1 with Comparative Examples 1 and 2, the raw material ratio mainly affects the ratio of yeast and mold in the koji, which directly affects the saccharification and fermentation of the koji and is one of the key factors affecting the final wine quality. Comparing Example 1 with Comparative Examples 3 and 4, it is found that the single fermentation process, regardless of the temperature, will lead to the extinction of yeast in the koji, and secondly, it will also lead to too low a total ester content in the koji, all of which will seriously reduce the quality of the koji.

[0059] Example 3

[0060] A tea-flavor and wine-flavor composite low-intoxication tea wine is prepared by the following steps:

[0061] S5. Select corn, wheat and sorghum with full grains, no mold and impurities and suitable moisture content in a weight ratio of 1:1:1 and mix them evenly as food raw materials. According to the general method in the art, the food raw materials are sequentially washed, soaked, steamed and saccharified to obtain grain dregs;

[0062] S6. Add 20% by mass of the tea wine yeast prepared in Example 1 to the grain lees, and seal and ferment at about 27°C for 40 days to obtain a fermented grain;

[0063] S7. Adding 40% of the mass of the mixed tea leaves to the grain raw material under sterile conditions and mixing evenly, and then continuing to ferment at about 27°C for 5 days;

[0064] S8. After the fermentation is completed, the wine is distilled and distilled in three stages, and the distilled wine is the tea wine product;

[0065] The mixed tea is obtained by uniformly mixing dried Ya'an Tibetan tea, Sichuan red tea, Gongmei tea and rock tea in a mass ratio of 10:3:3:3, and the mixed tea is sterilized before adding.

[0066] Comparative Example 5

[0067] A tea wine is prepared, which differs from Example 3 in that, in S6, the koji of Example 1 is replaced with commercially available Daqu (Shengyuan Biological), and the remaining steps are the same.

[0068] Comparative Example 6

[0069] A tea wine was prepared by extending the fermentation time in S7 to 30 days based on Comparative Example 5.

[0070] Comparative Example 7

[0071] A tea wine was prepared, which differed from Example 3 in that the mixed tea leaves were added before the fermentation started. That is, the mixed tea leaves, which accounted for 40% of the mass of the grain raw materials, were added to the grain dregs and stirred evenly, and then the tea wine special koji was added, and then the mixture was sealed and fermented directly at about 27° C. for 45 days, and the wine was distilled.

[0072] Professionals conducted a sensory evaluation on the tea wine products brewed in the above examples, and the evaluation results are shown in Table 2 below.

[0073] Table 2

[0074]

[0075]

[0076] Comprehensive two-dimensional gas chromatography-time of flight mass spectrometry (GC×GC TOF MS) technology and liquid chromatography-mass spectrometry (LC-MS) were used to analyze the components of tea wine. Table 3 Relative flavor activity values ​​(ROAV) and aroma description of volatile components in tea wine.

[0077] Table 3

[0078]

[0079] As can be seen from Table 2, the tea wine of Example 3 has a more unique flavor than the wine brewed with general Daqu. The brewing time of Comparative Example 5 is the same as that of Example 3, but its tea aroma is on the low side, which has certain weaknesses. The flavor and taste of Comparative Example 6 are both good, but the fermentation time is too long, which is not conducive to cost control. The brewing process of Comparative Example 7 is slightly different from that of Example 3, and there is also the disadvantage of low tea aroma. According to Table 3, in Example 3, the aroma activity values ​​of substances such as ethyl isovalerate and ethyl caproate that produce rich aromas are higher than those of Comparative Examples 5 and 6, while the aroma activity values ​​of aroma substances such as dimethyl trisulfide with fishy smell are lower. The tea wine provided by the present invention has a more mellow flavor, and the tea aroma and wine aroma are more integrated and revealed, forming a unique tea wine quality, which is better than Comparative Examples 5-7.

[0080] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for preparing special distiller's yeast for tea wine, characterized in that: The following steps are involved: S1. Raw material preparation: by weight, take 4-8 parts of barley, 85-95 parts of wheat and 2-5 parts of tea, mix well and crush, and adjust the moisture content to 50-70% to obtain koji raw materials; S2. Billet making: making the koji raw materials into koji billets; S3. Cultivating the koji blank: culturing the koji blank at 18-25° C. until the temperature of the koji blank is constant; S4. Secondary fermentation: The temperature is raised to 40-50°C to perform secondary fermentation on the koji until the moisture content of the koji drops to 12-15%, thereby obtaining the special koji for tea wine.

2. The method for preparing a special distiller's yeast for tea wine according to claim 1, characterized in that: In S1, the tea leaves include at least two of green tea, oolong tea, black tea, white tea, dark tea or yellow tea.

3. The method for preparing a special distiller's yeast for tea wine according to claim 1, characterized in that: In S1, the fineness of the koji-making raw material is 50-80 mesh.

4. The method for preparing a special distiller's yeast for tea wine according to claim 1, characterized in that: In S2, the size of the curved blank is 20-30cm×15-20cm×10-15cm.

5. The method for preparing a special distiller's yeast for tea wine according to claim 1, characterized in that: In S2, the method for making the curved blank is mechanical pressing or manual pressing.

6. A special distiller's yeast for tea wine obtained by the preparation method according to any one of claims 1 to 5.

7. Use of the special distiller's yeast for tea wine according to claim 6 in brewing tea wine.

8. The use of the tea wine special koji according to claim 7 in brewing tea wine, comprising using the tea wine special koji as a fermentation agent to prepare a tea wine with a composite tea aroma and wine aroma, and the preparation method of the tea wine with a composite tea aroma and wine aroma comprises the following steps: Select high-quality grain raw materials, and carry out the steps of washing, soaking, steaming and saccharification in sequence to obtain grain waste; Adding the tea wine special koji to the grain dregs, sealing and fermenting for 40-50 days to obtain dregs; Adding mixed tea leaves to the fermented grains under aseptic conditions and stirring evenly, and then continuing fermentation under the same conditions for 3-7 days; After fermentation is complete, the wine is distilled.

9. The use of the special distiller's yeast for tea wine according to claim 8 in brewing tea wine, characterized in that: The addition amount of the special distiller's yeast for tea wine is 15-25% of the mass of the grain dregs.

10. The use of the special distiller's yeast for tea wine according to claim 8 in brewing tea wine, characterized in that: The mixed tea is obtained by uniformly mixing yellow tea, black tea, red tea and white tea in a mass ratio of 10-20:1-10:2-12:2-10.

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