A process for improving liquor quality by preparing functional bacteria liquid with yellow water

Abstract

The present application provides a process for improving liquor quality by using yellow water to prepare functional bacteria liquid, comprising: distilling yellow water to prepare yellow water distillation liquor, and using the yellow water distillation liquor as raw material to prepare liquid culture medium; using the liquid culture medium to culture functional bacteria to prepare functional bacteria liquid; before the pit grain dregs are put into the barrel, a batch of functional bacteria liquid corresponding to 1-9 (wt) ‰ of the added glutinous sorghum is added, and then the barrel fermentation is carried out, and the remaining process is carried out according to the conventional liquor making process. The process of the present application can recycle and utilize the yellow water, and the prepared liquor can effectively reduce the content of harmful impurities such as fusel oil, can significantly reduce the drunkenness degree value, and can improve the liquor quality.

Description

Technical Field

[0001] This invention relates to the field of baijiu brewing technology, and in particular to a process for improving the quality of baijiu by using yellow water to prepare functional bacterial solutions. Background Technology

[0002] Yellow water is a brownish-yellow, slightly viscous, turbid liquid that settles at the bottom of the fermentation pit during the solid-state fermentation of baijiu (Chinese liquor). This occurs because some water seeps out of the mash under the action of microorganisms. Normally fermented yellow water has an alcohol content of 7-10% vol, a pH of 3.0-3.5, and possesses a cellar aroma and ester aroma. It is a viscous, turbid liquid with a distinct astringent and sour taste. Many baijiu companies treat yellow water as wastewater generated during production, which not only wastes this resource but also increases their wastewater treatment costs.

[0003] Fusel oil is an inevitable byproduct of baijiu fermentation, significantly impacting its taste and quality. A suitable amount of fusel oil can impart unique aromas, enrich the flavor, enhance harmony, and create a pleasant and comfortable experience. However, excessive fusel oil can make the baijiu bitter, astringent, and pungent, easily causing a hangover and posing certain toxic effects. Therefore, reducing fusel oil content is one of the most pressing technical challenges. Summary of the Invention

[0004] In view of this, the present invention proposes a process for improving the quality of baijiu by preparing functional bacterial solution using yellow water, aiming to improve the quality of baijiu and reduce fusel oils while recycling yellow water.

[0005] The technical solution of this invention is implemented as follows: This invention provides a process for preparing functional bacterial solutions using yellow water to improve the quality of baijiu (Chinese liquor), comprising:

[0006] Preparation of liquid culture medium: Yellow water is distilled to obtain yellow water distilled liquor, which is then used to prepare liquid culture medium;

[0007] Preparation of functional bacterial solution: Functional bacterial solution is prepared by inoculating functional bacteria in liquid culture medium and then carrying out deep fermentation.

[0008] Preparation of grain mash for use in the fermentation tank: A batch of glutinous sorghum is soaked, steamed initially, steamed again, cooled, saccharified and incubated with bacteria, and then mixed with grain residue to prepare grain mash for use in the fermentation tank.

[0009] Add functional bacterial solution to the grain mash before it enters the tank: Before the grain mash is put into the tank, take 1-9 (wt)‰ of the functional bacterial solution of one batch of glutinous sorghum to be added, and mix it evenly with the grain mash.

[0010] Fermentation in barrels: After the grain mash mixed with functional bacteria solution is placed in barrels and sealed, it is fermented for 15-30 days at 20-22℃.

[0011] Distillation: The fermented mash is distilled in a still, and the head and tail are removed to obtain brewed wine.

[0012] Earthenware jar aging: The distilled wine is placed in an earthenware jar and left to age.

[0013] In some embodiments, the preparation method of the above-mentioned functional bacterial solution includes the following steps:

[0014] Preparation of primary seed culture: Under aseptic conditions, add distilled yellow water to the primary seed culture medium until the alcohol content reaches 3-10% vol. Remove the cultured slant bacteria from the test tubes and inoculate 3 loops of functional bacteria into the primary seed culture medium with an inoculation loop. Then place it in a 30℃ constant temperature shaker and incubate at 140 rpm for 18-28 hours.

[0015] Secondary seed culture preparation: Under aseptic conditions, add yellow water distilled liquor to the secondary seed culture medium until the alcohol content reaches 3-10% vol. Inoculate the mature primary seed culture medium with 5-10% vol. Set the fermentation temperature to 27-35℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. Culture for 10-18 hours.

[0016] Preparation of functional bacterial culture: Under aseptic conditions, add distilled liquor to the functional bacterial liquid fermentation medium until the alcohol content reaches 3-10% vol. Inoculate the secondary seed liquid into the functional bacterial liquid fermentation medium at 5-10% vol. Set the fermentation temperature to 27-35℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add distilled liquor to adjust the alcohol content of the fermentation liquid to 3-3.5% vol until the dissolved oxygen in the fermentation liquid no longer decreases and the dissolved oxygen is ≥80%. Fermentation is then complete, and the functional bacterial culture is obtained.

[0017] In some embodiments, the added distilled yellow liquor contains 0.5-0.7% vol of nutrients during the preparation of the functional bacterial solution.

[0018] In some embodiments, the functional bacteria are a mixture of yeast, lactic acid bacteria and acetic acid bacteria.

[0019] In some embodiments, the primary seed culture medium and the secondary seed culture medium have the same formula, both prepared by mixing 10g glucose, 10g yeast extract and 980ml distilled water and sterilizing at 115°C for 20min, in 1L.

[0020] In some embodiments, the functional bacterial liquid fermentation medium is prepared by mixing 20g glucose, 10g yeast extract, 10g peptone, and 970ml distilled water and then sterilizing at 115°C for 30min, in 1L.

[0021] In some embodiments, the method for preparing the mash for feeding into the tank includes:

[0022] Soaking the grain: Put a batch of glutinous sorghum into warm water at 60-70℃, ensuring that the water surface covers the grain, and let it soak for 19-21 hours;

[0023] First steaming: After soaking, drain the water from the glutinous sorghum, put it into a steamer, and steam at 100-120℃ for 15-20 minutes.

[0024] Steaming the grains: Add 50-60℃ warm water to a steamer and steam the grains for 3-5 minutes;

[0025] Re-steaming: After the grain has finished steaming, drain the water and steam for 10-15 minutes.

[0026] Cooling: Remove the re-steamed glutinous sorghum and let it cool to room temperature.

[0027] Saccharification and incubation: Mix the yeast evenly into the cooked glutinous sorghum that has cooled to room temperature, and let it stand to saccharify and incubate.

[0028] Grain and lees mixing: After saccharification and bacterial culture are completed, the saccharified mash and the fresh lees obtained from distillation on the same day are mixed evenly at a mass ratio of 1:(1-1.5) and cooled to room temperature to obtain the grain mash for distillation.

[0029] In some implementations, the moisture content of the cooked glutinous sorghum prepared by the re-steaming step is controlled at 48-52%.

[0030] In some embodiments, the specific method of saccharification and cultivation includes: adding 0.8-1.2 (wt)% of green-clothed Guanyin koji (a type of starter culture) of glutinous sorghum to the cooled grain, mixing evenly, and then saccharifying and cultivating for 22-24 hours.

[0031] In some embodiments, the reducing sugar content of the prepared mash is controlled between 0.5 and 1.2.

[0032] The present invention has the following advantages over the prior art:

[0033] (1) This invention obtains distilled liquor from yellow water by re-distilling it, and then uses the distilled liquor as the main raw material to prepare a liquid culture medium. Functional bacterial liquid is obtained by inoculating functional bacteria and then fermenting it in a liquid deep fermentation process. This process can effectively utilize the ethanol in the yellow water, avoid the waste of ethanol caused by directly treating the yellow water as production wastewater, reduce wastewater treatment costs, and improve the efficiency of enterprises.

[0034] (2) By adding functional bacterial solution in the process of entering the pool, the present invention can significantly reduce the production of fusel oil, reduce the alcohol content, and improve the quality of the wine. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a process flow diagram of the present invention for preparing functional bacterial solutions using yellow water to improve the quality of baijiu. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this invention pertain. If any definition stated in this section is contrary to or otherwise inconsistent with a definition stated in a patent, patent application, published patent application, or other publication incorporated herein by reference, the definitions listed here shall prevail over those incorporated herein by reference.

[0040] Unless otherwise specified, the methods used in the following embodiments are conventional methods. Unless otherwise specified, the materials, reagents, and instruments used are conventional materials, reagents, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0041] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1 to 5” is disclosed, the described range should be interpreted as including ranges “1 to 4”, “1 to 3”, “1 to 2”, “1 to 2 and 4 to 5”, “1 to 3 and 5”, etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range. In this specification and claims, range definitions may be combined and / or interchanged, unless otherwise stated, these ranges include all subranges contained therein.

[0042] The yeast used in this embodiment of the invention is the Green Guanyin yeast produced by Jingpai Co., Ltd.

[0043] The functional bacteria used in the embodiments of this invention were screened by the microbiology laboratory of Kingboard Ltd.

[0044] Example 1

[0045] Preparation of functional bacterial culture:

[0046] A primary seed culture medium was prepared by mixing 10g glucose, 10g yeast extract and 980mL distilled water and sterilizing at 115℃ for 20min.

[0047] A secondary seed culture medium was prepared by mixing 200g glucose, 200g yeast extract and 19.6L distilled water and sterilizing at 115℃ for 20min.

[0048] A functional bacterial liquid fermentation medium was prepared by mixing 8 kg of glucose, 4 kg of yeast extract, 4 kg of peptone, and 388 L of distilled water and sterilizing at 115 °C for 30 min.

[0049] Add distilled yellow water to the primary seed culture medium until the alcohol content reaches 3% vol. Inoculate with a three-ring mixture of yeast, lactic acid bacteria and acetic acid bacteria, and then place in a 30℃ constant temperature shaker and culture at 140 rpm for 18 h to obtain the primary seed culture.

[0050] Add yellow distilled liquor to the secondary seed culture medium until the alcohol content reaches 3% vol. Inoculate the primary seed culture medium with 5% vol. Set the fermentation temperature to 27℃. Adjust the fermenter to maintain dissolved oxygen at 30-60%. Cultivate for 10 hours to obtain the secondary seed culture.

[0051] Add distilled yellow liquor to the functional bacterial culture medium until the alcohol content reaches 3% vol. Inoculate the secondary seed liquid into the functional bacterial liquid culture medium at 5% vol. Set the fermentation temperature to 27℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add distilled yellow liquor (containing 0.5% vol of nutrients) to adjust the alcohol content of the fermentation liquid to 3% vol. Continue until the dissolved oxygen in the fermentation liquid no longer decreases and is ≥80%, and the rotation speed of the fermenter is 100-150 rpm. Fermentation is then complete, and the functional bacterial culture is obtained.

[0052] Baijiu brewing:

[0053] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out and cooled to room temperature. 1.2 (wt)% of the amount of green Guanyin koji (a type of starter culture) from the batch of glutinous sorghum was mixed in and stirred evenly. The mixture was then placed in a box at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content between 1 and 2. The saccharified mash and the fresh mash obtained from distillation that day were mixed evenly at a ratio of 1:1.5 to obtain the mash to be fed into the fermentation tank. Then, 1‰ (wt) of functional bacteria solution from the batch of glutinous sorghum was evenly added. The mash mixed with functional bacteria solution was placed in sealed barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash was distilled in a still, and the heads and tails were discarded to obtain solid-state baijiu.

[0054] Example 2

[0055] Preparation of functional bacterial culture:

[0056] A primary seed culture medium was prepared by mixing 10g glucose, 10g yeast extract and 980mL distilled water and sterilizing at 115℃ for 20min.

[0057] A secondary seed culture medium was prepared by mixing 200g glucose, 200g yeast extract and 19.6L distilled water and sterilizing at 115℃ for 20min.

[0058] A functional bacterial liquid fermentation medium was prepared by mixing 8 kg of glucose, 4 kg of yeast extract, 4 kg of peptone, and 388 L of distilled water and sterilizing at 115 °C for 30 min.

[0059] Add distilled yellow water to the primary seed culture medium until the alcohol content reaches 6% vol. Inoculate with a mixture of three functional bacteria (yeast, lactic acid bacteria and acetic acid bacteria) and place in a constant temperature shaker at 30℃ for 22 hours at 140 rpm to obtain the primary seed culture.

[0060] Add distilled yellow liquor to the secondary seed culture medium until the alcohol content reaches 6% vol. Inoculate the primary seed culture medium with 7% vol. Set the fermentation temperature to 29℃. Adjust the fermenter to maintain dissolved oxygen at 30-60%. Culture for 12 hours to obtain the secondary seed culture.

[0061] Add distilled liquor to the functional bacterial culture medium until the alcohol content reaches 6% vol. Inoculate the secondary seed culture medium with 7% vol. Set the fermentation temperature to 29℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add distilled liquor (containing 0.6% vol of nutrients) to adjust the alcohol content of the fermentation broth to 3.2% vol. Continue until the dissolved oxygen in the fermentation broth no longer decreases and is ≥80%, and the fermenter speed is 100-150 rpm. Fermentation is then complete, and the functional bacterial culture is obtained.

[0062] Baijiu brewing:

[0063] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% of the green Guanyin koji (a type of starter culture) of the batch of glutinous sorghum. The mixture was then placed in a box at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh mash obtained from distillation that day were mixed evenly at a ratio of 1:1.5 to obtain the mash to be fed into the fermentation tank. Then, 3‰ (wt) functional bacteria solution of the same batch of glutinous sorghum was evenly added. The mash mixed with functional bacteria solution was placed in sealed barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash was distilled in a still, and the heads and tails were discarded to obtain solid-state baijiu.

[0064] Example 3

[0065] Preparation of functional bacterial culture:

[0066] A primary seed culture medium was prepared by mixing 10g glucose, 10g yeast extract and 980mL distilled water and sterilizing at 115℃ for 20min.

[0067] A secondary seed culture medium was prepared by mixing 200g glucose, 200g yeast extract and 19.6L distilled water and sterilizing at 115℃ for 20min.

[0068] A functional bacterial liquid fermentation medium was prepared by mixing 8 kg of glucose, 4 kg of yeast extract, 4 kg of peptone, and 388 L of distilled water and sterilizing at 115 °C for 30 min.

[0069] Add distilled yellow water to the primary seed culture medium until the alcohol content reaches 8% vol. Inoculate with a mixture of yeast, lactic acid bacteria and acetic acid bacteria, and place in a constant temperature shaker at 30℃ for 25 hours at 140 rpm to obtain the primary seed culture.

[0070] Add yellow distilled liquor to the secondary seed culture medium until the alcohol content reaches 8% vol. Inoculate the primary seed culture medium with 8% vol. Set the fermentation temperature to 32℃. Adjust the fermenter to maintain dissolved oxygen at 30-60%. Cultivate for 16 hours to obtain the secondary seed culture.

[0071] Add distilled liquor to the functional bacterial culture medium until the alcohol content reaches 8% vol. Inoculate the secondary seed culture into the functional bacterial liquid culture medium at 9% vol. Set the fermentation temperature to 32℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add distilled liquor (containing 0.6% vol of nutrients) to adjust the alcohol content of the fermentation broth to 3.4% vol. Continue until the dissolved oxygen in the fermentation broth no longer decreases and is ≥80%, and the fermenter speed is 100-150 rpm. Fermentation is then complete, and the functional bacterial culture is obtained.

[0072] Baijiu brewing:

[0073] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% of the green Guanyin koji (a type of starter culture) of the batch of glutinous sorghum. The mixture was then placed in a box at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh mash obtained from distillation that day were mixed evenly at a ratio of 1:1.5 to obtain the mash to be fed into the fermentation tank. Then, 5‰ (wt) functional bacteria solution of the same batch of glutinous sorghum was evenly added. The mash mixed with functional bacteria solution was placed in sealed barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash was distilled in a still, and the heads and tails were discarded to obtain solid-state baijiu.

[0074] Example 4

[0075] Preparation of functional bacterial culture:

[0076] A primary seed culture medium was prepared by mixing 10g glucose, 10g yeast extract and 980mL distilled water and sterilizing at 115℃ for 20min.

[0077] A secondary seed culture medium was prepared by mixing 200g glucose, 200g yeast extract and 19.6L distilled water and sterilizing at 115℃ for 20min.

[0078] A functional bacterial liquid fermentation medium was prepared by mixing 8 kg of glucose, 4 kg of yeast extract, 4 kg of peptone, and 388 L of distilled water and sterilizing at 115 °C for 30 min.

[0079] Add distilled yellow water to the primary seed culture medium until the alcohol content reaches 10% vol. Inoculate with a three-ring mixture of yeast, lactic acid bacteria and acetic acid bacteria, and then place in a constant temperature shaker at 30℃ and culture at 140 rpm for 28 h to obtain the primary seed culture.

[0080] Add yellow distilled liquor to the secondary seed culture medium until the alcohol content reaches 10% vol. Inoculate the primary seed culture medium with 10% vol. Set the fermentation temperature to 35℃. Adjust the fermenter to maintain dissolved oxygen at 30-60%. Culture for 18 hours to obtain the secondary seed culture.

[0081] Add distilled liquor to the functional bacterial culture medium until the alcohol content reaches 10% vol. Inoculate the secondary seed culture into the functional bacterial liquid culture medium at 10% vol. Set the fermentation temperature to 35℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add distilled liquor (containing 0.7% vol of nutrients) to adjust the alcohol content of the fermentation broth to 3.5% vol. Continue until the dissolved oxygen in the fermentation broth no longer decreases and is ≥80%, and the fermenter speed is 100-150 rpm. Fermentation is then complete, and the functional bacterial culture is obtained.

[0082] Baijiu brewing:

[0083] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% of the green Guanyin koji (a type of starter culture) of the batch of glutinous sorghum. The mixture was then placed in a box at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh mash obtained from distillation that day were mixed evenly at a ratio of 1:1.5 to obtain the mash to be fed into the fermentation tank. Then, 9‰ (wt) of functional bacteria solution from the batch of glutinous sorghum was evenly added. The mash mixed with functional bacteria solution was then sealed in barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash was distilled in a still, and the heads and tails were discarded to obtain solid-state baijiu.

[0084] Comparative Example 1

[0085] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% of the green Guanyin koji (a type of starter culture) of the batch of glutinous sorghum. The mixture was then placed in a box at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh mash obtained from distillation that day are mixed evenly at a ratio of 1:1.5 to obtain the mash for fermentation. The mash is then sealed in barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash is distilled, and the first and last portions are discarded to obtain solid-state baijiu.

[0086] Comparative Example 2

[0087] Preparation of yeast fermentation broth:

[0088] It was prepared using Saccharomyces cerevisiae using conventional culture methods.

[0089] Baijiu brewing:

[0090] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% of the green Guanyin koji (a type of starter culture) of the batch of glutinous sorghum. The mixture was then placed in a container at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh lees obtained from distillation that day are mixed evenly at a ratio of 1:1.5 to obtain the mash for fermentation. Before entering the fermentation tank, a yeast fermentation solution of 3‰ of the glutinous sorghum used in that batch is poured over it. The mash with the yeast solution is then sealed in barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash is distilled in a still, and the heads and tails are discarded to obtain solid-state baijiu.

[0091] Comparative Example 3

[0092] Preparation of yeast fermentation broth:

[0093] It was prepared using Saccharomyces cerevisiae using conventional culture methods.

[0094] Baijiu brewing:

[0095] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% pure Rhizopus from the batch of glutinous sorghum. The mixture was then placed in a container at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh lees obtained from distillation that day are mixed evenly at a ratio of 1:1.5 to obtain the mash for fermentation. Before entering the fermentation tank, a yeast fermentation solution of 3‰ of the glutinous sorghum used in that batch is poured over it. The mash with the yeast solution is then sealed in barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash is distilled in a still, and the heads and tails are discarded to obtain solid-state baijiu.

[0096] Comparative Example 4

[0097] Preparation of functional bacterial culture:

[0098] A primary seed culture medium was prepared by mixing 10g glucose, 10g yeast extract and 980mL distilled water and sterilizing at 115℃ for 20min.

[0099] A secondary seed culture medium was prepared by mixing 200g glucose, 200g yeast extract and 19.6L distilled water and sterilizing at 115℃ for 20min.

[0100] A functional bacterial liquid fermentation medium was prepared by mixing 8 kg of glucose, 4 kg of yeast extract, 4 kg of peptone, and 388 L of distilled water and sterilizing at 115 °C for 30 min.

[0101] Add fresh wine to the primary seed culture medium until the alcohol content reaches 3% vol. Inoculate with a three-ring mixture of yeast, lactic acid bacteria and acetic acid bacteria, and then place in a 30°C constant temperature shaker and culture at 140 rpm for 18 h to obtain the primary seed culture.

[0102] Add fresh wine to the secondary seed culture medium until the alcohol content reaches 3% vol. Inoculate the primary seed culture medium with 5% vol. Set the fermentation temperature to 27℃. Adjust the fermenter to maintain dissolved oxygen at 30-60%. Cultivate for 10 hours to obtain the secondary seed culture.

[0103] Add fresh wine to the functional bacterial fermentation medium until the alcohol content reaches 3% vol. Inoculate the secondary seed liquid into the functional bacterial liquid medium at 5% vol. Set the fermentation temperature to 27℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add fresh wine (containing 0.5% vol of nutrients) to adjust the alcohol content of the fermentation liquid to 3% vol. Continue until the dissolved oxygen in the fermentation liquid no longer decreases and is ≥80%, and the rotation speed of the fermenter is 100-150 rpm. Fermentation is then complete, and the functional bacterial liquid is obtained.

[0104] Baijiu brewing:

[0105] A batch of glutinous sorghum was added to 60℃ warm water, ensuring the water level covered the grains, and left to soak for 21 hours. After soaking, the glutinous sorghum was drained and placed into an oval stainless steel ball pot, which was sealed with a lid with a vent. Steam was then introduced and steamed at 100-120℃ for 15 minutes. After steaming, 50℃ warm water was added to cover the grains by 10cm and steamed for 5 minutes. The steaming water was then drained, and steam was introduced for 10 minutes until the moisture content of the cooked grains was between 48-52%. The cooked grains were then poured out, cooled to room temperature, and mixed with 1.2 (wt)% pure Rhizopus from the batch of glutinous sorghum. The mixture was then placed in a container at 21-25℃ and saccharified at 26-30℃ for 24 hours to obtain saccharified mash with a reducing sugar content of 1-2. The saccharified mash and the fresh lees obtained from distillation that day are mixed evenly at a ratio of 1:1.5 to obtain the mash for fermentation. Before entering the fermentation tank, a yeast fermentation solution of 3‰ of the glutinous sorghum used in that batch is poured over it. The mash with the yeast solution is then sealed in barrels and fermented at 20-22℃ for 25 days. After fermentation, the mash is distilled in a still, and the heads and tails are discarded to obtain solid-state baijiu.

[0106] The liquors prepared in Examples 1-4 and Comparative Examples 1-4 were evaluated for alcohol yield, key chromatographic properties, and sensory characteristics, and the results are shown in the table below:

[0107]

[0108] As can be seen from the data in the above embodiments and comparative examples, by using the technical solution of the present invention to prepare functional bacterial liquid using yellow water, the content of defective components such as fusel oil in the brewed raw wine can be significantly reduced. Compared with Comparative Example 4, it can be seen that the functional bacterial liquid prepared using conventional wine liquid cannot achieve a similar effect. Compared with Comparative Example 1, it can be seen that when no functional bacterial liquid is used, a similar effect cannot be achieved. Compared with Comparative Examples 2 and 3, it can be seen that when using Green Guanyin koji, there is also a certain degree of improvement in the quality of the wine. However, compared with Comparative Example 2, it can be seen that when other functional bacterial liquids are used, a similar effect cannot be achieved.

[0109] The alcohol intoxication levels of mice were tested using Example 2 (experimental group), Comparative Example 1 (control group), and 95% ethanol (0# original liquor), respectively, and the results are shown in the table below:

[0110]

[0111] Note: Compared with the control group, "*" indicates P < 0.05, and "**" indicates P < 0.01.

[0112] As can be seen from the data in the table above, the process of preparing functional bacterial liquid from yellow water to improve the quality of baijiu using the technical solution of this invention results in a lower alcohol content of the raw liquor compared to the control group. The alcohol content of the experimental group is 51.26 (≤95), indicating a trend of reduced alcohol content. Specifically, the intoxication occurs more slowly after drinking and the recovery is faster.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for preparing functional bacterial solutions using yellow water to improve the quality of baijiu (Chinese liquor), characterized in that, include: Yellow water distillation is used to prepare yellow water distilled liquor, and the yellow water distilled liquor is used as a raw material to prepare liquid culture medium; Functional bacterial solution is prepared by culturing functional bacteria in liquid culture medium; before the grain mash is put into the tank, 1-9 wt‰ of the functional bacterial solution of the glutinous sorghum to be added is added, and then the mash is put into the tank for fermentation. The remaining process is carried out according to the conventional baijiu brewing process. The preparation method of the functional bacterial solution includes the following steps: Preparation of primary seed culture: Under aseptic conditions, distilled yellow liquor is added to the primary seed culture medium until the alcohol content reaches 3-10% vol. After inoculation with functional bacteria, the medium is placed in a constant temperature shaker at 30℃ and cultured at 140 rpm for 18-28 hours. The functional bacteria are a mixed strain of yeast, lactic acid bacteria and acetic acid bacteria. Secondary seed culture preparation: Under aseptic conditions, add yellow water distilled liquor to the secondary seed culture medium until the alcohol content reaches 3-10% vol, and inoculate the primary seed culture medium with 5-10% vol. Set the fermentation temperature to 27-35℃, adjust the fermenter to maintain dissolved oxygen at 30-60%, and culture for 10-18 hours. Preparation of functional bacterial culture: Under aseptic conditions, add distilled yellow liquor to the functional bacterial liquid fermentation medium until the alcohol content reaches 3-10% vol. Inoculate the secondary seed liquid into the functional bacterial liquid fermentation medium at 5-10% vol. Set the fermentation temperature to 27-35℃ and adjust the fermenter to maintain dissolved oxygen at 30-60%. When the alcohol content of the liquid fermentation medium is lower than 1.0% vol, slowly add distilled yellow liquor to adjust the alcohol content of the fermentation liquid to 3-3.5% vol until the dissolved oxygen of the fermentation liquid no longer decreases and the dissolved oxygen is ≥80%. Fermentation is then complete, and the functional bacterial culture is obtained.

2. The process for preparing functional bacterial solutions to improve the quality of baijiu using yellow water as described in claim 1, characterized in that, The primary and secondary seed culture media have the same formula, both prepared by mixing 10g glucose, 10g yeast extract and 980ml distilled water and then sterilizing at 115℃ for 20min.

3. The process for preparing functional bacterial solutions to improve the quality of baijiu using yellow water as described in claim 1, characterized in that, The functional bacterial liquid fermentation medium was prepared by mixing 20g glucose, 10g yeast extract, 10g peptone, and 970ml distilled water and then sterilizing at 115℃ for 30min.

4. The process for preparing functional bacterial solutions to improve the quality of baijiu using yellow water as described in claim 1, characterized in that, The methods for preparing grain mash for use in fermentation include: Soaking the grain: Put a batch of glutinous sorghum into warm water at 60-70℃, ensuring that the water surface covers the grain, and let it soak for 19-21 hours; First steaming: After soaking, drain the water from the glutinous sorghum, put it into a steamer, and steam at 100-120℃ for 15-20 minutes. Steaming the grains: Add 50-60℃ warm water to a steamer and steam the grains for 3-5 minutes; Re-steaming: After the grain has been steamed, drain the steaming water and steam for 10-15 minutes. Cooling: Remove the re-steamed glutinous sorghum and let it cool to room temperature. Saccharification and incubation: Mix the yeast evenly into the cooked glutinous sorghum that has cooled to room temperature, and let it stand to saccharify and incubate. Grain and lees mixing: After saccharification and bacterial culture are completed, the saccharified mash and the fresh lees obtained from distillation on the same day are mixed evenly at a mass ratio of 1:(1-1.5) and cooled to room temperature to obtain the grain mash for distillation.

5. The process for preparing functional bacterial solutions to improve the quality of baijiu using yellow water as described in claim 4, characterized in that, The moisture content of the cooked glutinous sorghum prepared by the re-steaming step is controlled at 48-52%.

6. The process for preparing functional bacterial solutions to improve the quality of baijiu using yellow water as described in claim 4, characterized in that, The specific method for saccharification and microbial cultivation includes: adding 0.8-1.2 wt% of green-clothed Guanyin koji (a type of starter culture) of glutinous sorghum to the cooled grain, mixing evenly, and then saccharifying and cultivating for 22-24 hours.

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