Brewing method of fen-flavor liquor

Abstract

The invention discloses a brewing method of fen-flavor liquor, and belongs to the technical field of liquor brewing.According to the technical scheme, the brewing method of the fen-flavor liquor is characterized by comprising the following steps that S1, sorghum is treated; s2, adding hot water into the sorghum, uniformly stirring, and stacking; s3, carrying out large-steam rice grain steaming on the rice grain moistened sorghum; s4, adding cold water into the steamed material, and uniformly stirring and mixing; s5, uniformly stirring and mixing the yeast powder and the sorghum to obtain a haw material; s6, fermenting in a cylinder, and taking out a large-hawthorn fermented material; s7, uniformly stirring and mixing the hawthorn fermented material and auxiliary materials, and distilling to obtain hawthorn wine; s8, adding water into the fermented grains distilled in the step S7, spreading for cooling, adding yeast powder to obtain secondary hawthorn materials, adding after-run into each jar after the secondary hawthorn materials are put into the jars, and sealing and fermenting; and S9, uniformly stirring and mixing the secondary hawthorn fermented material and the steamed auxiliary materials, distilling to obtain secondary hawthorn wine, and storing the secondary hawthorn wine. By adopting the brewing method, the wine yield of the fen-flavor white wine is increased, and meanwhile, the mellow and sweet taste of the wine body is also increased.

Description

Technical Field

[0001] This invention relates to the field of brewing technology, and in particular to a method for brewing a light-aroma type of baijiu (Chinese liquor). Background Technology

[0002] In the field of baijiu brewing, light-aroma baijiu, as one of the four major aroma types of baijiu in my country, holds a unique position. It is made from grains through traditional solid-state fermentation, distillation, aging, and blending, without the addition of edible alcohol or non-fermented aroma compounds. It possesses a complex aroma primarily composed of ethyl acetate and ethyl lactate, and its taste is characterized by a smooth entry and a sweet finish. As consumers' demands for baijiu quality and taste continue to rise, the market demand for light-aroma baijiu is gradually expanding. The development of its brewing technology is of great significance in meeting market demand and promoting the progress of the baijiu industry.

[0003] In existing technologies, the conventional method used in the brewing of light-aroma baijiu is mainly the traditional solid-state fermentation process. This typically involves first crushing grains such as sorghum, then moistening and steaming them, followed by the addition of yeast for fermentation. After fermentation, the baijiu is distilled, aged, and blended. However, the crushing process is often simply a matter of grinding the sorghum into a certain size; the amount and temperature of hot water added during moistening are not precisely controlled; the steam pressure and time during steaming lack strict standards; and the temperature and time control during fermentation are relatively rudimentary. While these conventional methods can produce light-aroma baijiu to some extent, the overall brewing process lacks refinement and scientific rigor.

[0004] However, these conventional methods in the existing technology have obvious shortcomings. The current production process of light-aroma baijiu has the problem of low alcohol yield, and the resulting light-aroma baijiu has a relatively thin flavor and insufficient sweetness, which cannot well meet consumers' demand for high-quality, rich-tasting light-aroma baijiu. Summary of the Invention

[0005] In order to solve the problems in the prior art, the present invention provides a brewing method for light-aroma baijiu. The brewing method of this application improves the yield of light-aroma baijiu and also increases the mellow sweetness of the liquor.

[0006] The brewing method for a light-aroma baijiu provided by this invention adopts the following technical solution: A method for brewing a light-aroma baijiu (Chinese liquor) includes the following steps: S1. Crush the sorghum into 4-8 pieces, with 25-35% of the fine powder passing through a 1.2mm sieve, less than 0.2% of whole grains, and less than 0.5% of husk content; S2, Moistening: Add 65-71% of the weight of the sorghum in hot water at a temperature of 78-93℃ to the above sorghum, stir evenly, and then pile it up at a temperature of 44-52℃ for 18-20 hours. S3. Steaming: Evenly place the moistened sorghum into the steamer. After steaming, sprinkle in hot water at a temperature of 60-65℃, which is 25-29% of the weight of the moistened sorghum. Steam for more than 80 minutes and then remove from the steamer. The steam pressure is 0.08-0.20MPa. S4. Add slurry: Add 25-29% of the original sorghum weight of cold water to the steamed material after steaming, and stir to mix evenly. S5. Cool the koji powder. The amount of koji powder is 9-10% of the weight of the sorghum raw material. After the koji powder and sorghum are mixed evenly, the koji powder is obtained. S6. Ferment in a vat: Sprinkle Daqu powder at the bottom of the fermentation vat and then fill it with hawthorn material. Seal and ferment for 20-25 days at a temperature of 10-15℃. Then take out the fermented hawthorn material. S7. Mix the hawthorn fermentation material and 70% of the steamed auxiliary material by weight of the hawthorn fermentation material evenly, then load the mixture into a still for distillation to obtain hawthorn wine. S8. After adding water to the mash after distillation in step S7 and cooling it, add 10% of the weight of the mash with Daqu powder to obtain the second batch of mash. The moisture content of the second batch of mash is 59-61.5% and the temperature of the mash is 17-22℃. After entering the vat, add 1kg of tail liquor with an alcohol content of 25-30%vol to each vat and seal it for fermentation for 25-30 days. S9. Mix the fermented hawthorn material and 30% of the steamed auxiliary material of the fermented hawthorn material evenly, then load the mixture into a still for distillation to obtain the alcohol from the fermented hawthorn and store it.

[0007] By adopting the above technical solution, sorghum is crushed into 4-8 pieces, ensuring that 25-35% of the fine powder passes through a 1.2mm sieve. This allows the starch molecules in the sorghum to be fully exposed, making gelatinization easier and providing sufficient usable starch for subsequent fermentation. Simultaneously, excessive crushing is avoided to prevent rapid heating, sticky mash, and contamination by other microorganisms, ensuring the stability of the fermentation process. Hot water at 78-93℃ is added during the initial soaking process; the high temperature promotes the dissolution and transformation of some beneficial components in the sorghum, resulting in a sweeter and more mellow liquor. During the first fermentation of the second batch of sorghum, Daqu powder is sprinkled at the bottom of the vat, allowing for full contact between the Daqu powder and the sorghum, providing a favorable microbial environment for fermentation, promoting fermentation, and enhancing the flavor and quality of the liquor. During the second fermentation of the third batch of sorghum, 1kg of 25-30% vol distillate is added to each vat. The components in the distillate participate in the fermentation process, enriching the taste and flavor of the liquor and further improving its quality. The entire brewing method can increase the yield of light-aroma baijiu, improve the flavor of the liquor, and enhance its mellow sweetness.

[0008] In a preferred embodiment, the Daqu powder is composed of Qingchaqu, Hongxinqu, and Houhuoqu in a weight ratio of 3:3:4.

[0009] By adopting the above technical solution, the koji powder composed of Qingchaqu, Hongxinqu, and Houhuoqu in a weight ratio of 3:3:4 is used for sorghum fermentation. Qingchaqu imparts a refreshing aroma and flavor to the fermentation process, laying the foundation for the flavor of light-aroma baijiu. Hongxinqu contains abundant microorganisms and enzymes, which can promote the decomposition and transformation of substances in sorghum, increase the vitality and efficiency of fermentation, and help generate more aroma and flavor substances. Houhuoqu can continuously provide fermentation power in the later stage of fermentation, making the fermentation more complete and enhancing the mellowness and fullness of the liquor. The synergistic effect of the three can increase the alcohol yield of sorghum, improve the problem of thin flavor and insufficient sweetness in light-aroma baijiu, and make the brewed light-aroma baijiu more fragrant and mellow and sweet.

[0010] In a preferred embodiment, the auxiliary material for the hawthorn fermentation feed is composed of rice bran and rice husk in a weight ratio of (3-4):(6-7).

[0011] In a preferred embodiment, the auxiliary material used in the fermentation feed is rice husk.

[0012] In a preferred embodiment, the proportion of the Daqu powder that passes through a 20-mesh sieve is 4-18%, and the proportion of the powder that passes through an 80-mesh sieve is 14-26%.

[0013] By adopting the above technical solution, the proportion of sifted material of different mesh sizes of Daqu powder is specified, which helps to increase the yield of light-aroma Baijiu and improve the problems of thin flavor and insufficient sweetness.

[0014] In a preferred embodiment, the fermentation temperature control in step S6 is as follows: from day 0 to day 7 after entering the fermentation tank, the temperature is raised to 22-26°C; from day 8 to day 15, the temperature is raised to 28-33°C; and from day 16 until exiting the fermentation tank, the temperature is lowered to 20-23°C.

[0015] In a preferred embodiment, the temperature rise rate during the first 0-7 days after entering the cylinder is 1-2°C / day; and the temperature drop rate from day 16 to exiting the cylinder is 0.5-1°C / day.

[0016] By adopting the above technical solution, during the first 0-7 days of hawthorn fermentation, the yeast and aroma-producing microorganisms in the koji (fermentation starter) are allowed to multiply fully through slow heating, initiating alcoholic fermentation and laying the foundation for flavor compound formation. Simultaneously, limiting the heating rate within this range prevents excessively rapid heating, which could lead to premature yeast aging, excessive production of higher alcohols, and off-flavors. In the middle stage (days 8-15), the temperature is maintained within the range of 28-33℃ to maximize alcohol production and the initial synthesis of flavor compounds. From day 16 until the fermentation is completed, esterification, cell autolysis, and microbial protein degradation are promoted, generating more active ingredients and increasing the wine's richness and sweetness.

[0017] In a preferred embodiment, the fermentation temperature control in step S8 is as follows: from day 0 to day 5 after the product is placed in the fermentation tank, the temperature rises to 28-32°C; from day 6 to day 18, the temperature stabilizes at 27-30°C; and from day 19 until the product is removed from the fermentation tank, the temperature drops to 23-25°C.

[0018] In a preferred embodiment, the heating rate during the first 0-5 days after entering the tank is 2-3°C / day.

[0019] By adopting the above technical solution, the saccharification and esterification reactions of residual starch are rapidly initiated within 0-5 days by utilizing the relatively high initial temperature and aroma precursors in the tails of the wine. Therefore, the daily temperature increase is controlled within the range of 2-3℃ to facilitate ester synthesis and acid-alcohol conversion. During the stable esterification period of 6-18 days, temperature control effectively promotes the balanced formation of ethyl acetate and ethyl lactate, as well as the accumulation of sweet alcoholic substances. From day 19 until the wine is removed from the fermentation tank, deep esterification and alcoholization can take place, further generating sweet substances such as glycerol and cyclodextrin, making the wine more mellow and smooth.

[0020] In a preferred embodiment, the material layer height during step S7 and step S7 loading and distillation is 0.6-0.8m.

[0021] By adopting the above technical solution, when the material layer is too high, the aroma-enhancing vapor has a short residence time in the cap; when the material layer is too low, the content of flavor substances in this component decreases or even disappears.

[0022] In summary, the present invention has the following beneficial effects: by controlling the process parameters in each step and precisely regulating the fermentation temperature, this application effectively improves the flavor and quality of the wine. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the embodiments. All reagents, unless otherwise specified, are commercially available conventional reagent products.

[0024] Sorghum quality requirements: Northern japonica sorghum should be selected. The content requirements of each component in the sorghum are as follows: moisture ≤14%, starch 62-65%, protein 10.3-12.5%, bulk density ≥725g / L, fat 3.6-44%, crude fiber 1.8-2.8%, ash 1.7-2.3%.

[0025] Quality requirements for Daqu: Moisture content of Qingchaqu ≤14%, moisture content of Houhuoqu and Hongxinqu ≤13%, saccharification power ≥750mg glucose / (gqu·h), liquefaction power ≥0.7g starch / (gqu·60℃·h).

[0026] Quality requirements for auxiliary materials: The rice husks should be yellow and bright in color, with normal coarse rice husks, broken into 2-3 pieces, free from rot, spoilage, greasiness, pesticide or fertilizer odors, and impurities not exceeding 2%; The rice husks are light yellow in color, broken into 2-3 pieces, and free from rot, spoilage, greasiness, pesticide or fertilizer odors, and impurities not exceeding 1%. Example 1

[0027] A method for brewing a light-aroma baijiu (Chinese liquor) includes the following steps: S1. Crush the sorghum into 4-8 pieces, with 25% being fine powder passing through a 1.2mm sieve, 0.1% being whole grains, and 0.2% containing husks. S2, Moistening: Add 65% of the weight of the sorghum in hot water at a temperature of 78°C to the above sorghum, stir evenly, and then pile it up at a temperature of 44°C for 20 hours. S3. Steaming: Evenly place the moistened sorghum into the steamer. After steaming, sprinkle in hot water at a temperature of 60°C, which is 25% of the weight of the moistened sorghum. Steam for more than 80 minutes and then remove from the steamer. The steam pressure is 0.08 MPa. S4. Add slurry: Add 25% of the original sorghum weight of cold water to the steamed material after steaming, and stir to mix evenly. S5. Cooling and removing the starter culture: The amount of starter culture powder used is 9% of the weight of the sorghum raw material. After the starter culture powder and sorghum are mixed evenly, the starter culture material is obtained. The starter culture powder is composed of stubble starter culture, red heart starter culture and post-fire starter culture in a weight ratio of 3:3:4. The proportion of the starter culture powder that passes through a 20-mesh sieve is 4%, and the proportion of the material that passes through an 80-mesh sieve is 14%. S6. Fermentation in the vat: After cleaning the fermentation vat, brush it with pepper water. Then sprinkle 0.25kg of Daqu powder at the bottom of the fermentation vat and put in the hawthorn material. The vat temperature is 10℃ for sealed fermentation. From 0 to 7 days after entering the vat, raise the temperature to 24℃ at a rate of 2℃ / day. From 8 to 15 days, raise the temperature to 28℃. From 16 to 20 days, remove the fermented hawthorn material from the vat and lower the temperature to 23℃ at a rate of 1℃. S7. Mix the fermented hawthorn material and 70% of the steamed auxiliary material of the fermented hawthorn material evenly, and then load them into a still for distillation. The material layer height is 0.6m when loading the still. After 35 minutes of distillation, the hawthorn liquor is obtained. The auxiliary material consists of rice bran and rice husk in a weight ratio of 3:7. S8. Take out the distilled mash from step S7, add water and cool it down. Then add 10% of the weight of the mash with Daqu powder (the same as the Daqu powder mentioned above) to obtain the second batch of mash. The moisture content of the second batch of mash is 60% and the temperature is 17℃. After entering the vat, add 1kg of 25% vol alcohol tails to each vat, seal and ferment. From 0 to 5 days after entering the vat, raise the temperature to 32℃ at a rate of 3℃ / day. From 6 to 18 days, stabilize the temperature at 30℃. From 19 to 25 days, remove the mash from the vat and take out the fermented mash after the temperature drops to 25℃. S9. Mix the fermented hawthorn material and 30% of the steamed auxiliary material of the fermented hawthorn material evenly, then load them into a still for distillation. The material layer height is 0.6m when loading the still. After distilling for 25 minutes, the distilled hawthorn liquor is obtained and stored. Example 2

[0028] A method for brewing a light-aroma baijiu (Chinese liquor) includes the following steps: S1. Crush the sorghum into 4-8 pieces, with 30% being fine powder that passes through a 1.2mm sieve, 0.1% being whole grains, and 0.4% containing husks. S2, Moistening: Add 68% of the weight of the sorghum in hot water at a temperature of 85°C to the above sorghum, stir evenly, and then pile it up at a temperature of 48°C for 20 hours. S3. Steaming: Evenly place the moistened sorghum into the steamer. After steaming, add hot water at 60°C, which is 29% of the weight of the moistened sorghum. Steam for more than 80 minutes and then remove from the steamer. The steam pressure is 0.1 MPa. S4. Add slurry: Add 29% of the original sorghum weight of cold water to the steamed material after steaming, and stir to mix evenly. S5. Cooling and removing the starter culture: The amount of starter culture powder used is 9% of the weight of the sorghum raw material. After the starter culture powder and sorghum are mixed evenly, the starter culture material is obtained. The starter culture powder is composed of stubble starter culture, red heart starter culture and post-fire starter culture in a weight ratio of 3:3:4. The proportion of the starter culture powder that passes through a 20-mesh sieve is 12%, and the proportion of the material that passes through an 80-mesh sieve is 20%. S6. Fermentation in the vat: After cleaning the fermentation vat, brush it with pepper water. Then sprinkle 0.25kg of Daqu powder at the bottom of the fermentation vat and put in the hawthorn material. The vat temperature is 15℃ for sealed fermentation. From 0 to 7 days after entering the vat, raise the temperature to 22℃ at a rate of 1℃ / day. From 8 to 15 days, raise the temperature to 30℃. From 16 to 22 days, remove the fermented hawthorn material from the vat and lower the temperature to 23℃ at a rate of 1℃. S7. Mix the fermented hawthorn material and 70% of the steamed auxiliary material by weight evenly, then load the mixture into a still for distillation. The material layer height is 0.8m when loading the still. After 35 minutes of distillation, the hawthorn liquor is obtained. The auxiliary material consists of rice bran and rice husk in a weight ratio of 4:6. S8. Take out the distilled mash from step S7, add water and cool it down. Then add 10% of the weight of the mash with Daqu powder (the same as the Daqu powder mentioned above) to obtain the second batch of mash. The moisture content of the second batch of mash is 59% and the temperature is 20°C when it is put into the vat. After it is put into the vat, add 1 kg of 30% vol alcohol tails to each vat, seal and ferment. From 0 to 5 days after it is put into the vat, raise the temperature to 30°C at a rate of 2°C / day. From 6 to 18 days, the temperature is stabilized at 28°C. From the 19th day until it is taken out of the vat, the temperature drops to 24°C and the second batch of mash fermentation material is taken out. S9. Mix the fermented hawthorn material and 30% of the steamed auxiliary material of the fermented hawthorn material evenly, and then load them into a still for distillation. The material layer height is 0.8m when loading the still. After 25 minutes of distillation, the distilled hawthorn liquor is obtained and stored. Example 3

[0029] A method for brewing a light-aroma baijiu (Chinese liquor) includes the following steps: S1. Crush the sorghum into 4-8 pieces, with 35% being fine powder that passes through a 1.2mm sieve, 0.1% being whole grains, and 0.2% containing husks. S2, Moistening: Add 71% of the weight of the sorghum in hot water at a temperature of 93°C to the above sorghum, stir evenly, and then pile it up at a temperature of 52°C for 18 hours. S3. Steaming: Evenly place the moistened sorghum into the steamer. After steaming, add hot water at 65°C, which is 29% of the weight of the moistened sorghum. Steam for more than 80 minutes and then remove from the steamer. The steam pressure is 0.20 MPa. S4. Add slurry: Add 29% of the original sorghum weight of cold water to the steamed material after steaming, and stir to mix evenly. S5. Cooling and removing the starter culture: The amount of starter culture powder used is 10% of the weight of the sorghum raw material. After the starter culture powder and sorghum are mixed evenly, the starter culture material is obtained. The starter culture powder is composed of stubble starter culture, red heart starter culture and post-fire starter culture in a weight ratio of 3:3:4. The proportion of the starter culture powder that passes through a 20-mesh sieve is 18%, and the proportion of the material that passes through an 80-mesh sieve is 26%. S6. Fermentation in the vat: After cleaning the fermentation vat, brush it with pepper water. Then sprinkle 0.25kg of Daqu powder at the bottom of the fermentation vat and fill it with hawthorn material. The vat temperature is 15℃ for sealed fermentation. From 0 to 7 days after filling the vat, raise the temperature to 22℃ at a rate of 1-2℃ / day. From 8 to 15 days, raise the temperature to 33℃. From 16 to 25 days, remove the fermented hawthorn material from the vat and lower the temperature to 23℃ at a rate of 1℃. S7. Mix the fermented hawthorn material and 70% of the steamed auxiliary material by weight evenly, then load the mixture into a still for distillation. The material layer height is 0.8m when loading the still. After 35 minutes of distillation, the hawthorn liquor is obtained. The auxiliary material consists of rice bran and rice husk in a weight ratio of 4:6. S8. After distilling the mash in step S7, add water and let it cool. Then add 10% of the weight of the mash with Daqu powder (the same as the Daqu powder mentioned above) to obtain the second batch of mash. The moisture content of the second batch of mash is 61.5% and the temperature is 22℃. After entering the vat, add 1kg of 30% vol alcohol tails to each vat, seal and ferment. From 0 to 5 days after entering the vat, raise the temperature to 32℃ at a rate of 2℃ / day. From 6 to 18 days, stabilize the temperature at 30℃. From the 19th to the 30th day, remove the mash from the vat and take out the fermented mash when the temperature drops to 25℃. S9. Mix the fermented hawthorn material and 30% of the steamed auxiliary material of the fermented hawthorn material evenly, and then load them into a still for distillation. The material layer height is 0.8m when loading the still. After 25 minutes of distillation, the distilled hawthorn liquor is obtained and stored. Comparative Example 1

[0030] A method for brewing a light-aroma baijiu differs from Example 1 in that, in step S6, the temperature at each stage is not strictly controlled when the hawthorn stalks are put into the fermentation tank. After being put into the tank, the fermentation temperature can be kept within the range of 23-28℃ during the 0-20 day fermentation period. All other steps are the same as in Example 1. Comparative Example 2

[0031] A method for brewing a light-aroma baijiu differs from Example 1 in that, in step S8, the temperature at each stage is not strictly controlled when the two raw materials are put into the fermentation tank. After being put into the tank, the fermentation temperature can be kept within the range of 25-32℃ during the fermentation period of 0-25 days. All other steps are the same as in Example 1. Comparative Example 3

[0032] A method for brewing a light-aroma baijiu differs from Example 1 in that, in step S6, the temperature of each stage of fermentation of the large hawthorn stalks is not strictly controlled; the fermentation temperature can be maintained within the range of 23-28℃ during the 0-20 day fermentation period after the stalks are placed in the fermentation tank. In step S8, the temperature of each stage of fermentation of the second hawthorn stalks is not strictly controlled; the fermentation temperature can be maintained within the range of 25-32℃ during the 0-25 day fermentation period after the stalks are placed in the fermentation tank. All other steps are the same as in Example 1. Performance testing

[0033] The baijiu obtained in the above examples and comparative examples were tested for total acid, total ester, ethyl acetate, ethyl lactate, ethyl hexanoate, and total alcohol yield in accordance with the provisions of GB / T1078.1-2022. The test results are shown in Table 1.

[0034] Table 1. Test results of various physicochemical properties and alcohol yield of Baijiu. project Total acid g / L Total esters g / L Ethyl acetate g / L Ethyl lactate g / L Ethyl hexanoate g / L Alcohol yield % Example 1 0.68 4.03 2.62 0.83 0.015 50.1 Example 2 0.71 4.12 2.75 0.86 0.013 51.3 Example 3 0.72 4.08 2.76 0.85 0.013 50.9 Comparative Example 1 1.13 3.24 1.89 1.23 0.213 52.4 Comparative Example 2 1.01 3.55 2.16 1.18 0.431 48.6 Comparative Example 3 1.67 2.87 1.52 1.67 0.684 51.6 Based on the data in Table 1: The total acidity of the baijiu obtained in Examples 1-3 of this application is below 1 g / L, ensuring that the light-aroma baijiu has a mellow sweetness, a clean taste, and a long aftertaste. Excessive total acidity results in a sharp, astringent taste, affecting the mellow sweetness. A total ester content above 4 g / L ensures the basic fullness of the baijiu's aroma, making it sufficiently fragrant; however, excessive total ester content leads to a cloying aroma and a lack of freshness. An ethyl acetate content above 2.6 g / L provides sufficient fruity aroma. If the content of ethyl lactate is too low, the fruity aroma will be insufficient; if it is too high (>3g / L), the aroma will be pungent and monotonous. Ethyl lactate provides a smooth and mellow feel, but the aroma is dull. Therefore, if the content of ethyl lactate is too high, the liquor will become dull and astringent, with a musty taste, which will seriously destroy the refreshing feeling. Ethyl hexanoate is the main aroma of strong aroma liquor, with a pineapple aroma, but in light aroma liquor, it is considered an "exotic aroma" or "mixed flavor". Therefore, the lower the content of ethyl hexanoate, the purer the light aroma liquor can be.

[0035] Compared with Example 1, when the hawthorn material was fermented without precise temperature control at each stage, the total acid content of the liquor obtained in Comparative Example 1 increased. This is because the higher average temperature is conducive to the metabolism of acid-producing bacteria such as lactic acid bacteria, increasing the accumulation of organic acids. The total ester content decreased because slow fermentation at low temperatures is conducive to ester synthesis. Higher temperatures lead to a faster fermentation rate, a shorter esterification reaction time, and the possibility that high temperatures may inhibit enzyme activity, resulting in a reduction in total ester accumulation. The ethyl lactate content increased because lactic acid bacteria are more active at higher temperatures, increasing lactic acid production and leading to an increase in ethyl lactate content after esterification. The ethyl hexanoate content also increased slightly due to the higher average temperature.

[0036] Compared with Example 1, in Comparative Example 2, when the temperature at each stage of fermentation was not precisely controlled, the contents of total acid, ethyl lactate, and ethyl hexanoate all increased significantly, while the contents of total ester and ethyl acetate decreased. The reasons for this were the same as those in Comparative Example 1.

[0037] Compared with Example 1, Comparative Example 3 showed that when the fermentation temperature of both hawthorn and jujube materials was not precisely controlled, the total acid content, ethyl lactate content, and ethyl hexanoate content all increased significantly, while the total ester content and ethyl acetate content decreased significantly. This resulted in a severe deficiency of the main aroma of the liquor. Although the liquor yield of Comparative Examples 1-3 was close to that of Example 1, the quality of the liquor was significantly lower than that of Example 1. Therefore, it can be seen that after the present application performs precise control of the fermentation temperature of hawthorn and jujube fermentation materials, the low temperature stage promotes yeast reproduction and alcoholic fermentation, and accumulates ethyl acetate precursors; the medium temperature stage balances ester conversion and inhibits miscellaneous bacteria; and the cooling stage promotes esterification and enriches the body of the liquor.

[0038] The embodiments described herein are merely illustrative of preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for brewing a light-aroma type of baijiu, characterized in that: Includes the following steps: S1. Crush the sorghum into 4-8 pieces, with 25-35% of the fine powder passing through a 1.2mm sieve, less than 0.2% of whole grains, and less than 0.5% of husk content; S2, Moistening: Add 65-71% of the weight of the sorghum in hot water at a temperature of 78-93℃ to the above sorghum, stir evenly, and then pile it up at a temperature of 44-52℃ for 18-20 hours. S3. Steaming: Evenly place the moistened sorghum into the steamer. After steaming, sprinkle in hot water at a temperature of 60-65℃, which is 25-29% of the weight of the moistened sorghum. Steam for more than 80 minutes and then remove from the steamer. The steam pressure is 0.08-0.20MPa. S4. Add slurry: Add 25-29% of the original sorghum weight of cold water to the steamed material after steaming, and stir to mix evenly. S5. Cool the koji powder. The amount of koji powder is 9-10% of the weight of the sorghum raw material. After the koji powder and sorghum are mixed evenly, the koji powder is obtained. S6. Ferment in a vat: Sprinkle Daqu powder at the bottom of the fermentation vat and then fill it with hawthorn material. Seal and ferment for 20-25 days at a temperature of 10-15℃. Then take out the fermented hawthorn material. S7. Mix the hawthorn fermentation material and 70% of the steamed auxiliary material by weight of the hawthorn fermentation material evenly, then load the mixture into a still for distillation to obtain hawthorn wine. S8. After adding water to the mash after distillation in step S7 and cooling it, add 10% of the weight of the mash with Daqu powder to obtain the second batch of mash. The moisture content of the second batch of mash is 59-61.5% and the temperature of the mash is 17-22℃. After entering the vat, add 1kg of tail liquor with an alcohol content of 25-30%vol to each vat and seal it for fermentation for 25-30 days. S9. Mix the fermented hawthorn material and 30% of the steamed auxiliary material of the fermented hawthorn material evenly, then load the mixture into a still for distillation to obtain the alcohol from the fermented hawthorn and store it.

2. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The Daqu powder is composed of Qingchaqu, Hongxinqu, and Houhuoqu in a weight ratio of 3:3:

4.

3. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The auxiliary materials for the fermented hawthorn feed consist of rice bran and rice husk in a weight ratio of (3-4):(6-7).

4. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The auxiliary material used in the fermentation feed of the two hawthorns is rice husk.

5. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The proportion of the Daqu powder that passes through a 20-mesh sieve is 4-18%, and the proportion of the powder that passes through an 80-mesh sieve is 14-26%.

6. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The fermentation temperature control in step S6 is as follows: from day 0 to day 7 after entering the tank, the temperature is raised to 22-26℃; from day 8 to day 15, the temperature is raised to 28-33℃; from day 16 until exiting the tank, the temperature is lowered to 20-23℃.

7. The brewing method of a light-aroma baijiu according to claim 6, characterized in that: The heating rate during the first 0-7 days after entering the tank is 1-2℃ / day; the temperature decrease rate from day 16 until exiting the tank is 0.5-1℃ / day.

8. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The fermentation temperature control in step S8 is as follows: from day 0 to day 5 after entering the tank, the temperature rises to 28-32℃; from day 6 to day 18, the temperature stabilizes at 27-30℃; from day 19 until exiting the tank, the temperature drops to 23-25℃.

9. The brewing method of a light-aroma baijiu according to claim 8, characterized in that: The heating rate is 2-3℃ / day within 0-5 days after the cylinder is filled.

10. The brewing method of a light-aroma baijiu according to claim 1, characterized in that: The material layer height during step S7 and the loading of the still for distillation is 0.6-0.8m.