Preparation process of pure grain solid state fermentation white spirit
By optimizing the process flow of pure grain solid fermented liquor, including raw material processing, koji production and fermentation control, the problems of complex operation and low starch yield in the existing process are solved, and the production cost reduction and marketing convenience are achieved.
Patent Information
- Application Number
- CN202510425417.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-07
- Publication Date
- 2025-06-10
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The existing pure grain solid fermented liquor production process is complex, and the starch yields low, resulting in high production costs, which limits large-scale production and market promotion.
A process is adopted, including raw material selection and treatment, koji preparation, ingredients and grain moisturization, steaming and gelatinization, saccharification fermentation, fermentation, distillation, aging blending and filtration filling, and the fermentation efficiency and wine output rate are improved by controlling temperature, humidity and ventilation conditions.
The production process is simplified, the wine production rate during the fermentation process of raw materials is improved, the cost of raw materials is reduced, and the sale price is effectively controlled.
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Figure CN120118718A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of liquor brewing, and specifically to a production process for pure grain solid-state fermented liquor. Background Art
[0002] The pure grain solid-state liquor brewing method is a unique traditional process in the Chinese liquor industry, with a history of thousands of years. In the liquor industry, pure grain liquor refers to liquor products made from sorghum, corn, wheat, rice, glutinous rice, barley, buckwheat, and beans (excluding tubers) as raw materials, and fermented naturally in mud cellars, stone cellars, or containers such as ceramic, porcelain, and cement in a fully solid state or semi-solid state (applicable to rice-flavored liquor), and then distilled at high temperature. Such liquor is also called traditional process liquor. Since the liquor is made from grains as raw materials, fermented naturally, and distilled at high temperature, it has unique flavors, such as the four major flavors of strong, light, sauce, and rice, and is loved by many people.
[0003] However, when the existing production process for pure grain solid-state fermented liquor is in production and processing, its production operation is complex, and the liquor yield rate of starch is relatively low, resulting in a relatively high cost for the entire production and processing, directly affecting the later selling cost, and restricting large-scale production and market promotion.
[0004] Therefore, a production process for pure grain solid-state fermented liquor is proposed to solve the above-mentioned problems. Summary of the Invention
[0005] The purpose of the present invention is to provide a production process for pure grain solid-state fermented liquor to solve the problems raised in the above background art.
[0006] To achieve the above purpose, the present invention provides the following technical solution: A production process for pure grain solid-state fermented liquor:
[0007] The specific steps of the production process for pure grain solid-state fermented liquor are as follows:
[0008] Step 1: Raw material selection and treatment: Select sorghum, wheat, corn, and rice that have been freshly harvested in recent years and have plump grains. Sort these raw materials to remove the stones or soil inside, as well as a small amount of incomplete or mildewed raw materials inside, and pour them into the internal part of a pulverizing device to be pulverized into particles with a size of 3 - 5 mm;
[0009] Step 2: Making Qu: Select wheat, wash it, dry it after washing, pour it into the interior of a crushing device, crush it into particles of 3 - 5 mm, add an appropriate amount of water and yeast, mix evenly, control the water content to be 40 - 45%, press the mixed raw materials into blocks to form Qu blanks, place the Qu blanks in a cultivation chamber, control the temperature of the cultivation chamber to be 30 - 40 °C and the humidity to be 60 - 70%, continuously cultivate for 7 - 14 days, and regularly turn the Qu blanks every 2 - 4 days during this period to ensure uniform fermentation. After cultivation, dry or air-dry the Qu blanks;
[0010] Step 3: Ingredients and Moistening Grains: Pour the crushed grain raw materials into a soaking device, pour in water to make the raw materials fully absorb water, so that the water content is 50 - 55%, and soak for 20 - 24 hours. After soaking, stack the moistened raw materials and add a certain amount of rice husk and bran, mix evenly, and let it further undergo a preliminary biochemical reaction in a moist environment to improve the fermentation efficiency;
[0011] Step 4: Steaming and Gelatinization: Load the moistened raw materials into a steamer or steamer basket, lay them in layers, heat and steam, control the steaming temperature at 100 - 120 °C, and it needs to last for 1 - 2 hours until the raw materials are completely cooked and emit a unique aroma, and during the steaming process, it is necessary to ensure uniform heat distribution. After steaming, quickly cool the raw materials to 30 - 40 °C for inoculating microorganisms;
[0012] Step 5: Saccharification and Fermentation: Sprinkle 15 - 25% of Daqu into the cooled raw materials per ton of raw materials, stir evenly, and ferment in an environment of 30 - 35 °C for 1 - 2 days. The enzymes in Daqu will gradually convert the gelatinized starch into fermentable sugars;
[0013] Step 6: Fermentation: During the saccharification process, the yeast in Daqu becomes active and converts sugars into alcohol and carbon dioxide. The fermentation process needs to strictly control the temperature at 28 - 32 °C, the humidity at 70 - 80% and the ventilation conditions to ensure the best growth environment for microorganisms. The entire fermentation process usually takes 7 - 15 days;
[0014] Step 7: Distillation: Load the fermented fermented grains into a distillation device, lay them in layers, heat with steam, control the temperature at 110 - 120 °C, and continue for 45 - 60 min to evaporate alcohol and other volatile components from the fermented grains;
[0015] Step 8: Aging and Blending: Usually use pottery jars, stainless steel tanks or oak barrel containers for aging, control the aging time at 6 - 8 months, mix different batches and different years of Baijiu in a certain proportion, adjust the alcohol content and flavor to make it reach a consistent quality standard;
[0016] Step 9: Filtration and bottling: Remove suspended solids and impurities in the liquor through filtration to make the liquor body clearer and more transparent. Fill the filtered white liquor into clean wine bottles, seal and store it. Conduct strict sensory and physical-chemical index tests on the finished product to ensure compliance with relevant standards.
[0017] Preferably, during the koji-making process, after the koji bricks are prepared, it is necessary to measure their enzyme activity and microbial diversity.
[0018] Preferably, the steps for measuring enzyme activity are as follows: Take 0.3 - 0.5 g of koji brick sample, add 8 - 10 mL of PBS buffer solution, oscillate and extract at 37 °C for 30 minutes, filter it, and take the supernatant as the enzyme solution for standby. Add 1 mL of 3% soluble starch solution and 1 mL of enzyme solution into a test tube, place the test tube in a 37 °C water bath for reaction for 8 - 10 minutes; add 2 mL of DNS reagent to terminate the reaction, and immediately put it into boiling water and boil for 5 minutes to make the reaction complete. After cooling to room temperature, measure the absorbance with a spectrophotometer at a wavelength of 540 nm. At the same time, set a blank control to correct the background absorbance, and calculate the enzyme activity. The calculation formula is as follows:
[0019] Enzyme activity (U / g) = ε × Vs × t × mΔA × Vt;
[0020] Where: ΔA: Absorbance difference;
[0021] Vt: Total volume (mL);
[0022] ε: Molar extinction coefficient;
[0023] Vs: Sample volume (mL);
[0024] T: Reaction time (min);
[0025] m: Sample mass (g).
[0026] Preferably, the specific steps for measuring the microbial diversity are as follows:
[0027] Randomly collect multiple samples from different batches or different locations of koji billets, put the collected koji billet samples into sterile sampling bags or centrifuge tubes, store them at 2-4°C, and send them to the laboratory for subsequent processing, crush the koji billet samples to 40 mesh and sieve them, accurately weigh 0.5g of the samples, add the weighed koji billet samples into a lysis buffer containing proteinase K and SDS components, mix them thoroughly, incubate them in a 65°C water bath for 30 minutes to 1 hour to lyse the cells, add an equal volume of phenol-chloroform mixture, shake them vigorously and centrifuge them, take the supernatant until the supernatant is clear and transparent, add 2 times the volume of cold ethanol or isopropanol to the supernatant, let it stand to precipitate DNA, collect the DNA precipitate by centrifugation, wash the precipitate with 70% ethanol, dry it and dissolve it in an appropriate amount of TE buffer or sterile water, and measure the DNA concentration and purity using a NanoDrop or Qubit fluorometer;
[0028] PCR amplification was performed using universal primers for the bacterial 16S rRNA V3-V4 region. The PCR reaction conditions were set as follows: 95°C pre-denaturation for 5 minutes, followed by 30 cycles, and a final extension at 72°C for 10 minutes. The amplified product was confirmed to have the correct band size by agarose gel electrophoresis;
[0029] The PCR products were end-repaired, A-tailed, and connected to adapters to construct sequencing libraries. Double-end 250bp sequencing was performed using the Illumina MiSeq platform to obtain at least 10,000 valid sequences for each sample;
[0030] Trimmomatic was used to remove low-quality sequences, and UPARSE was used for OTU clustering. The similarity threshold was set at 97%, and the OTU representative sequences were compared with the Greengenes database and annotated to the genus or species level. The alpha diversity index was calculated, and the beta diversity among different samples was compared by PCoA analysis.
[0031] Preferably, in step six, regular ventilation and oxygen supply are required in the early stage of fermentation to promote the reproduction of yeast, and ventilation should be reduced in the later stage to form an anaerobic environment, which is conducive to alcohol fermentation.
[0032] Preferably, in step eight, different brands and styles of liquor have different aging requirements and different aging times.
[0033] Preferably, in step nine, part of the liquor is also cold filtered or hot filtered to remove unstable components that affect the quality of the liquor.
[0034] Compared with the prior art, the present invention has the following beneficial effects:
[0035] The preparation process of this application is simple. When selecting raw materials, sorghum, wheat, corn, and rice that were freshly harvested in recent years and have plump grains are chosen to ensure that they contain sufficient starch inside. When crushing them, they are crushed into particles with a size of 3 - 5 mm, which can not only ensure good gelatinization effect but also maintain appropriate air permeability. This application greatly improves the liquor yield during the raw material fermentation process, correspondingly reduces the raw material cost, and can effectively control the selling price. BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Figure 1 It is a flowchart of the preparation steps of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.
[0038] Please refer to Figure 1 , the present invention provides a technical solution:
[0039] A pure grain solid-state fermentation white liquor production process:
[0040] The specific steps of this pure grain solid-state fermentation white liquor production process are as follows:
[0041] Step 1. Raw material selection and treatment: Select sorghum, wheat, corn, and rice that were freshly harvested in recent years and have plump grains to ensure the freshness of the raw materials and avoid using stale or moldy raw materials, as these will affect the fermentation effect. Sort these raw materials to remove stones or soil inside, as well as a small amount of incomplete or mildewed raw materials inside, and pour them into the crushing device to be crushed into particles with a size of 3 - 5 mm. If the crushing particle size is too fine, it will lead to poor air permeability during the fermentation process and affect the growth of microorganisms; while if the crushing particle size is too coarse, it will reduce the gelatinization and saccharification efficiency of starch.
[0042] Step 2. Making koji: Select wheat, wash it, and after washing, dry it. After drying, pour it into the crushing device to be crushed into particles with a size of 3 - 5 mm. Add an appropriate amount of water and yeast, mix evenly, control the water content to be 40 - 45%, press the mixed raw materials into blocks to form koji blocks. Put the koji blocks into the cultivation room, control the temperature of the cultivation room to be 30 - 40 degrees Celsius, and the humidity to be 60 - 70%, and continuously cultivate for 7 - 14 days. During this period, turn the koji blocks regularly every 2 - 4 days to ensure uniform fermentation. After cultivation, dry or air-dry the koji blocks.
[0043] Step 3, ingredients and grain moistening: pour the crushed grain raw materials into the soaking device, pour water, make the raw materials fully absorb water, make the water content at 50-55%, and soak for 20-24 hours. After the soaking is completed, pile up the moistened raw materials, add a certain amount of rice husks and bran, mix evenly, so as to adjust the air permeability and water absorption during the fermentation process. Too much auxiliary materials will dilute the fermentation matrix and affect the wine yield; too little may lead to poor air permeability, allowing it to further undergo preliminary biochemical reactions in a humid environment to improve the fermentation efficiency;
[0044] Step 4: Steaming and gelatinization: put the moistened raw materials into a steamer or steamer, lay them in layers, heat and steam them. The steaming temperature is controlled at 100-120℃ and needs to last for 1-2 hours until the raw materials are fully cooked and emit a unique aroma. During the steaming process, the heat distribution needs to be even. After the steaming is completed, the raw materials are quickly cooled to 30-40℃ for inoculation of microorganisms.
[0045] Step 5: Saccharification and fermentation: Add 15-25% of Daqu per ton of raw materials and sprinkle it into the cooled raw materials, stir evenly, and ferment at 30-35°C for 1-2 days. The enzyme in the Daqu will gradually convert the gelatinized starch into fermentable sugars.
[0046] Step 6: Fermentation: During the saccharification process, the yeast in the Daqu becomes active and converts sugars into alcohol and carbon dioxide. The fermentation process requires strict control of the temperature at 28-32°C, humidity at 70-80%, and ventilation conditions to ensure the best growth environment for microorganisms. The entire fermentation process usually takes 7-15 days.
[0047] Step 7: Distillation: The fermented mash is loaded into the distillation equipment, laid in layers, heated by steam, and the temperature is controlled at 110-120 degrees Celsius for 45-60 minutes to evaporate the alcohol and other volatile components from the mash;
[0048] Step 8: Aging and blending: ceramic jars, stainless steel tanks or oak barrels are usually used for aging. The aging time is controlled at 6-8 months. Different batches and different years of liquor are mixed in a certain proportion to adjust the alcohol content and flavor to achieve consistent quality standards.
[0049] Step 9. Filtration and filling: Remove suspended matter and impurities in the wine by filtering to make the wine clearer and more transparent. Fill the filtered liquor into clean bottles and store them in sealed containers. Conduct strict sensory and physical and chemical index tests on the finished product to ensure that it meets relevant standards.
[0050] In the process of koji making, after the koji is prepared, its enzyme activity and microbial diversity need to be measured.
[0051] The steps for enzyme activity determination are as follows: Take 0.3 - 0.5 g of koji sample, add 8 - 10 mL of PBS buffer, shake and extract at 37 °C for 30 minutes, filter it, and take the supernatant as the enzyme solution for standby. Add 1 mL of 3% soluble starch solution and 1 mL of enzyme solution into a test tube, place the test tube in a 37 °C water bath for reaction for 8 - 10 minutes; add 2 mL of DNS reagent to terminate the reaction, and immediately put it into boiling water and boil for 5 minutes to complete the reaction. After cooling to room temperature, measure the absorbance with a spectrophotometer at a wavelength of 540 nm. At the same time, set a blank control to correct the background absorbance, and calculate the enzyme activity. The calculation formula is as follows:
[0052] Enzyme activity (U / g) = ε × Vs × t × mΔA × Vt;
[0053] Where: ΔA: Absorbance difference;
[0054] Vt: Total volume (mL);
[0055] ε: Molar extinction coefficient;
[0056] Vs: Sample volume (mL);
[0057] T: Reaction time (min);
[0058] m: Sample mass (g).
[0059] The specific steps for the determination of microbial diversity are as follows:
[0060] Randomly collect multiple samples from koji of different batches or different locations. Put the collected koji samples into sterile sampling bags or centrifuge tubes, and store them at 2 - 4 °C, and send them to the laboratory for subsequent processing. Crush the koji samples to 40 mesh and sieve. Accurately weigh 0.5 g of the sample. Add the weighed koji sample to the lysis buffer, which contains protease K and SDS components. After thorough mixing, incubate in a 65 °C water bath for 30 minutes to 1 hour to lyse the cells. Add an equal volume of phenol-chloroform mixture, shake vigorously and then centrifuge. Take the supernatant until the upper layer of the supernatant is clear and transparent. Add 2 volumes of cold ethanol or isopropanol to the supernatant, let it stand to precipitate DNA, centrifuge to collect the DNA precipitate, wash the precipitate with 70% ethanol, dry it and dissolve it in an appropriate amount of TE buffer or sterile water, and use a NanoDrop or Qubit fluorometer to measure the DNA concentration and purity;
[0061] Use the universal primers for the V3 - V4 region of bacterial 16S rRNA for PCR amplification. Set the PCR reaction conditions as: pre-denaturation at 95 °C for 5 minutes, followed by 30 cycles, and finally extension at 72 °C for 10 minutes. Confirm the correct band size of the amplification product by agarose gel electrophoresis;
[0062] The PCR products were subjected to end repair, A-tailing and adapter ligation to construct a sequencing library, and paired-end 250-bp sequencing was performed using the Illumina MiSeq platform, with at least 10,000 valid sequences obtained for each sample.
[0063] Low-quality sequences were removed using Trimmomatic, OTU clustering was performed using UPARSE with a similarity threshold of 97%, the OTU representative sequences were aligned with the Greengenes database, annotated to the genus or species level, the α-diversity index was calculated, and the β-diversity between different samples was compared by PCoA analysis.
[0064] In step six, ventilation and oxygen supply should be carried out regularly in the initial stage of fermentation to promote the reproduction of yeast, and ventilation should be reduced in the later stage to form an anaerobic environment, which is beneficial to alcohol fermentation.
[0065] In step eight, different brands and styles of Baijiu have different aging requirements and different aging times.
[0066] In step nine, some Baijiu also undergoes cold filtration or heat filtration to remove unstable components that affect the quality of the liquor.
[0067] Example 1:
[0068] The specific steps of this pure grain and solid-state fermentation Baijiu production process are as follows:
[0069] Step 1. Raw material selection and treatment: Select recently harvested sorghum, wheat, corn, and rice with plump grains. Sort these raw materials to remove stones or soil inside, as well as a small amount of incomplete or moldy raw materials inside, and pour them into the internal part of a crushing device to be crushed into 3-mm particles.
[0070] Step 2. Starter making: Select wheat, wash it, dry it after washing, pour it into the internal part of a crushing device to be crushed into 3-mm particles, add an appropriate amount of water and yeast, mix evenly, control the water content to be 40%, press the mixed raw materials into blocks to form starter cakes, put the starter cakes into a cultivation chamber, control the temperature of the cultivation chamber to be 30 degrees Celsius and the humidity to be 60%, continuously cultivate for 7 days, and regularly turn the starter cakes every 2 days to ensure uniform fermentation. After cultivation, dry or air-dry the starter cakes.
[0071] Step 3. Ingredients preparation and grain moistening: Pour the crushed grain raw materials into a soaking device, pour in water to allow the raw materials to fully absorb water until the water content reaches 50%, soak for 20 hours. After soaking, pile up the moistened raw materials, add a certain amount of rice husk and bran, mix evenly, and let them undergo a preliminary biochemical reaction in a moist environment to improve the fermentation efficiency.
[0072] Step 4. Steaming and gelatinization: Load the moistened raw materials into a steamer or a bamboo steamer, lay them in layers, heat and steam. Control the steaming temperature at 100°C and continue for 1 hour until the raw materials are completely cooked and emit a unique aroma. During the steaming process, it is necessary to ensure uniform heat distribution. After steaming, quickly cool the raw materials to 30°C for inoculating microorganisms;
[0073] Step 5. Saccharification and fermentation: Sprinkle 15% of Daqu into the cooled raw materials per ton of raw materials, stir evenly, and ferment in an environment of 30°C for 1 day. The enzymes in Daqu will gradually convert the gelatinized starch into fermentable sugars;
[0074] Step 6. Fermentation: During the saccharification process, the yeast in Daqu becomes active and converts sugars into alcohol and carbon dioxide. The fermentation process needs to strictly control the temperature at 28 - 32°C, the humidity at 70%, and the ventilation conditions to ensure the best growth environment for microorganisms. The entire fermentation process usually takes 7 days;
[0075] Step 7. Distillation: Load the fermented fermented grains into the distillation equipment, lay them in layers, heat with steam, control the temperature at 110°C, and continue for 45 minutes to evaporate alcohol and other volatile components from the fermented grains;
[0076] Step 8. Aging and blending: Usually use pottery jars, stainless - steel tanks or oak barrels for aging. Control the aging time at 6 months. Mix different batches and different years of Baijiu in a certain proportion, adjust the alcohol content and flavor to make them meet the consistent quality standards;
[0077] Step 9. Filtration and bottling: Remove the suspended substances and impurities in the wine through filtration to make the wine body clearer and more transparent. Fill the filtered Baijiu into clean wine bottles, seal and store, and conduct strict sensory and physical - chemical index tests on the finished products to ensure compliance with relevant standards;
[0078] Example 2:
[0079] The specific steps of the pure - grain solid - state fermentation Baijiu production process are as follows:
[0080] Step 1. Raw material selection and treatment: Select recently harvested sorghum, wheat, corn, and rice with plump grains. Sort these raw materials, remove the internal stones or soil, as well as a small amount of incomplete or mildewed raw materials inside, and pour them into the internal part of the pulverizing device to pulverize them into 4 - mm particles;
[0081] Step 2: Qu Making: Select wheat, wash it, dry it after washing, pour it into the interior of a crushing device, crush it into 4-mm particles, add an appropriate amount of water and yeast, mix evenly, control the water content to be 42.5%, press the mixed raw materials into blocks to form qu blanks, place the qu blanks in a cultivation chamber, control the temperature of the cultivation chamber to be 35 °C and the humidity to be 65%, continuously cultivate for 10 days, regularly turn the qu blanks every 3 days during the period to ensure uniform fermentation, after cultivation is completed, dry or air-dry the qu blanks;
[0082] Step 3: Ingredients and Grain Moistening: Pour the crushed grain raw materials into a soaking device, pour in water to make the raw materials fully absorb water, so that the water content is 52.5%, and soak for 22 hours. After soaking is completed, stack the moistened raw materials, add a certain amount of rice husk and bran, mix evenly, and let it further undergo a preliminary biochemical reaction in a moist environment to improve the fermentation efficiency;
[0083] Step 4: Steaming and Gelatinization: Load the moistened raw materials into a steamer or steamer basket, lay them in layers, heat and steam, control the steaming temperature at 110 °C, and it needs to last for 1.5 hours until the raw materials are completely cooked and emit a unique aroma, and during the steaming process, it is necessary to ensure uniform heat distribution. After steaming is completed, quickly cool the raw materials to 35 °C for inoculating microorganisms;
[0084] Step 5: Saccharification and Fermentation: Sprinkle 20% of the daqu into the cooled raw materials per ton of raw materials, stir evenly, and ferment in an environment of 32.5 °C for 1.5 days. The enzymes in the daqu will gradually convert the gelatinized starch into fermentable sugars;
[0085] Step 6: Fermentation: During the saccharification process, the yeast in the daqu becomes active and converts sugars into alcohol and carbon dioxide. The fermentation process needs to strictly control the temperature at 30 °C, the humidity at 75%, and the ventilation conditions to ensure the best growth environment for microorganisms. The entire fermentation process usually takes 11 days;
[0086] Step 7: Distillation: Load the fermented fermented grains into a distillation device, lay them in layers, heat with steam, control the temperature at 115 °C, and continue for 52.5 min to evaporate alcohol and other volatile components from the fermented grains;
[0087] Step 8: Aging and Blending: Usually use pottery jars, stainless steel tanks or oak barrels for aging, control the aging time at 7 months, mix different batches and different years of baijiu in a certain proportion, adjust the alcohol content and flavor to make it reach a consistent quality standard;
[0088] Step Nine, Filtration and Bottling: Remove suspended solids and impurities in the liquor through filtration to make the liquor body clearer and more transparent. Fill the filtered liquor into clean wine bottles, seal and store it. Conduct strict sensory and physical-chemical index tests on the finished product to ensure compliance with relevant standards;
[0089] Example 3:
[0090] The specific steps of this pure grain solid-state fermentation liquor production process are as follows:
[0091] Step One, Raw Material Selection and Treatment: Select recently harvested sorghum, wheat, corn, and rice with plump grains. Sort these raw materials to remove stones or soil inside, as well as a small amount of incomplete or mildewed raw materials inside, and pour them into the internal part of the crushing device to crush them into particles of 5 mm;
[0092] Step Two, Starter Making: Select wheat, wash it, dry it after washing, pour it into the internal part of the crushing device to crush it into particles of 5 mm, add an appropriate amount of water and yeast, mix evenly, control the water content to be 45%, press the mixed raw materials into blocks to form starter cakes. Put the starter cakes into the cultivation room, control the temperature of the cultivation room to be 40 degrees Celsius and the humidity to be 70%, and cultivate continuously for 14 days. During this period, turn the starter cakes regularly every 4 days to ensure uniform fermentation. After cultivation, dry or air-dry the starter cakes;
[0093] Step Three, Ingredients and Moistening Grains: Pour the crushed grain raw materials into the soaking device, pour in water to make the raw materials fully absorb water, so that the water content is 55%, and soak for 24 hours. After soaking, pile up the moistened raw materials, add a certain amount of rice husk and bran, mix evenly, and let it further undergo a preliminary biochemical reaction in a humid environment to improve the fermentation efficiency;
[0094] Step Four, Cooking and Gelatinization: Load the moistened raw materials into a steamer or steamer basket, lay them in layers, heat and cook. Control the cooking temperature at 120 °C and continue for 2 hours until the raw materials are completely cooked and emit a unique aroma. During the cooking process, it is necessary to ensure uniform heat distribution. After cooking, quickly cool the raw materials to 40 °C for inoculating microorganisms;
[0095] Step Five, Saccharification and Fermentation: Sprinkle 25% of the Daqu into the cooled raw materials per ton of raw materials, stir evenly, and ferment in an environment of 35 °C for 2 days. The enzymes in the Daqu will gradually convert the gelatinized starch into fermentable sugars;
[0096] Step 6: Fermentation: During the saccharification process, the yeast in the Daqu starts to become active, converting sugars into alcohol and carbon dioxide. The fermentation process requires strict control of the temperature at 32°C, humidity at 80%, and ventilation conditions to ensure the optimal growth environment for microorganisms. The entire fermentation process usually takes 15 days;
[0097] Step 7: Distillation: The fermented fermented grains are loaded into the distillation equipment, laid in layers, and heated by steam. The temperature is controlled at 120°C and continued for 60 minutes to evaporate alcohol and other volatile components from the fermented grains;
[0098] Step 8: Aging and Blending: Usually, earthenware jars, stainless steel tanks, or oak barrels are used for aging. The aging time is controlled for 8 months. Baijiu from different batches and years is mixed in a certain proportion to adjust the alcohol content and flavor to reach a consistent quality standard;
[0099] Step 9: Filtration and Bottling: Remove the suspended solids and impurities in the wine through filtration to make the wine body clearer and more transparent. The filtered Baijiu is bottled into clean wine bottles, sealed and stored, and strict sensory and physical and chemical index tests are carried out on the finished product to ensure compliance with relevant standards.
[0100] The above shows and describes the basic principles, main features, and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present invention; therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention, and any reference signs in the claims should not be regarded as limiting the claims involved.
[0101] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A pure grain solid-state fermentation liquor production process, characterized by: The specific steps of the pure grain solid-state fermentation liquor production process are as follows: Step 1: Raw material selection and processing: Select sorghum, wheat, corn and rice that have just been harvested in recent years and have full grains, sort these raw materials, remove the stones or soil inside, as well as a small amount of incomplete or moldy raw materials inside, and pour them into the inside of the crushing device to crush them into 3-5mm particles; Step 2, koji making: select wheat, wash it, dry it after washing, pour it into the inside of the grinding device after drying, grind it into 3-5mm particles, add appropriate amount of water and yeast, mix evenly, control the moisture content to 40-45%, press the mixed raw materials into blocks to become koji blanks, put the koji blanks into a culture room, control the temperature of the culture room to 30-40 degrees Celsius, and the humidity to 60-70%, and continue to culture for 7-14 days. During this period, the koji blanks are regularly turned over every 2-4 days to ensure uniform fermentation. After the cultivation is completed, the koji blanks are air-dried or dried; Step 3: Mixing and moistening the grain: Pour the crushed grain raw materials into a soaking device, add water, allow the raw materials to fully absorb water, make the water content at 50-55%, and soak for 20-24 hours. After the soaking is completed, pile up the moistened raw materials, add a certain amount of rice husks and bran, mix them evenly, and allow them to further undergo preliminary biochemical reactions in a moist environment to improve the fermentation efficiency; Step 4: Steaming and gelatinization: put the moistened raw materials into a steamer or steamer, lay them in layers, heat and steam them. The steaming temperature is controlled at 100-120℃ and needs to last for 1-2 hours until the raw materials are fully cooked and emit a unique aroma. During the steaming process, the heat distribution needs to be even. After the steaming is completed, the raw materials are quickly cooled to 30-40℃ for inoculation of microorganisms. Step 5: Saccharification and fermentation: Add 15-25% of Daqu per ton of raw materials and sprinkle it into the cooled raw materials, stir evenly, and ferment at 30-35°C for 1-2 days. The enzyme in the Daqu will gradually convert the gelatinized starch into fermentable sugars. Step 6: Fermentation: During the saccharification process, the yeast in the Daqu becomes active and converts sugars into alcohol and carbon dioxide. The fermentation process requires strict control of the temperature at 28-32°C, humidity at 70-80%, and ventilation conditions to ensure the best growth environment for microorganisms. The entire fermentation process usually takes 7-15 days. Step 7: Distillation: The fermented mash is loaded into the distillation equipment, laid in layers, heated by steam, and the temperature is controlled at 110-120 degrees Celsius for 45-60 minutes to evaporate the alcohol and other volatile components from the mash; Step 8: Aging and blending: ceramic jars, stainless steel tanks or oak barrels are usually used for aging. The aging time is controlled at 6-8 months. Different batches and different years of liquor are mixed in a certain proportion to adjust the alcohol content and flavor to achieve consistent quality standards. Step 9. Filtration and filling: Remove suspended matter and impurities in the wine by filtering to make the wine clearer and more transparent. Fill the filtered liquor into clean bottles and store them in sealed containers. Conduct strict sensory and physical and chemical index tests on the finished product to ensure that it meets relevant standards.
2. A pure grain solid-state fermentation liquor production process according to claim 1, characterized in that: In the process of koji making, after the koji is prepared, its enzyme activity and microbial diversity need to be measured.
3. The process for producing pure grain solid-state fermented liquor according to claim 2, characterized in that: The enzyme activity determination steps are as follows: take 0.3-0.5g of koji sample, add 8-10mL PBS buffer, shake and extract at 37°C for 30 minutes, filter it, take the supernatant as enzyme solution for standby, add 1mL 3% soluble starch solution and 1mL enzyme solution in a test tube, place the test tube in a 37°C water bath for reaction for 8-10 minutes; add 2mL DNS reagent to terminate the reaction, and immediately put it into boiling water and boil for 5 minutes to complete the reaction, after cooling to room temperature, use a spectrophotometer to measure the absorbance at a wavelength of 540nm, set a blank control at the same time to correct the background absorbance, and calculate the enzyme activity. The calculation formula is as follows: Enzyme activity (U / g) = ε × Vs × t × mΔA × Vt; Where: ΔA: absorbance difference; Vt: total volume (mL); ε: molar extinction coefficient; Vs: sample volume (mL); T: reaction time (min); m: sample mass (g).
4. The process for producing pure grain solid-state fermented liquor according to claim 2, characterized in that: The specific steps of the microbial diversity determination are as follows: Randomly collect multiple samples from different batches or different locations of koji billets, put the collected koji billet samples into sterile sampling bags or centrifuge tubes, store them at 2-4°C, and send them to the laboratory for subsequent processing, crush the koji billet samples to 40 mesh and sieve them, accurately weigh 0.5g of the samples, add the weighed koji billet samples into a lysis buffer containing proteinase K and SDS components, mix them thoroughly, incubate them in a 65°C water bath for 30 minutes to 1 hour to lyse the cells, add an equal volume of phenol-chloroform mixture, shake them vigorously and centrifuge them, take the supernatant until the supernatant is clear and transparent, add 2 times the volume of cold ethanol or isopropanol to the supernatant, let it stand to precipitate DNA, collect the DNA precipitate by centrifugation, wash the precipitate with 70% ethanol, dry it and dissolve it in an appropriate amount of TE buffer or sterile water, and measure the DNA concentration and purity using a NanoDrop or Qubit fluorometer; PCR amplification was performed using universal primers for the bacterial 16S rRNA V3-V4 region. The PCR reaction conditions were set as follows: 95°C pre-denaturation for 5 minutes, followed by 30 cycles, and a final extension at 72°C for 10 minutes. The amplified product was confirmed to have the correct band size by agarose gel electrophoresis; The PCR products were end-repaired, A-tailed, and connected to adapters to construct sequencing libraries. Double-end 250bp sequencing was performed using the Illumina MiSeq platform to obtain at least 10,000 valid sequences for each sample; Trimmomatic was used to remove low-quality sequences, and UPARSE was used for OTU clustering. The similarity threshold was set at 97%, and the OTU representative sequences were compared with the Greengenes database and annotated to the genus or species level. The alpha diversity index was calculated, and the beta diversity among different samples was compared by PCoA analysis.
5. The process for producing pure grain solid-state fermented liquor according to claim 1, characterized in that: In step six, regular ventilation and oxygen supply are required in the early stage of fermentation to promote the reproduction of yeast, while ventilation should be reduced in the later stage to form an anaerobic environment, which is conducive to alcohol fermentation.
6. The process for producing pure grain solid-state fermented liquor according to claim 1, characterized in that: In step eight, different brands and styles of liquor have different aging requirements and different aging times.
7. The process for producing pure grain solid-state fermented liquor according to claim 1, characterized in that: In step nine, some liquors are also cold filtered or hot filtered to remove unstable components that affect the quality of the liquor.