Preparation method of cereal brewed cooking wine with high amino acid nitrogen content and preparation method thereof

Abstract

The invention discloses a preparation method of cereal brewed cooking wine with high amino acid nitrogen content and a preparation method thereof. Belongs to the technical field of food processing. The preparation method comprises the following steps: firstly, taking fried wheat / rice and / or soybeans as raw materials, and mixing according to a specific proportion to prepare finished koji; and secondly, saccharifying the cereal raw materials, and sequentially performing primary fermentation, low-temperature secondary fermentation and after-ripening fermentation to prepare a finished product. Through the cooperation of the composite starter-making raw materials and the multi-stage fermentation process, especially the combination of low-temperature secondary fermentation and high-alcoholic-strength after-ripening, the conversion of proteins is significantly promoted, and infectious microbes are effectively inhibited, so that the content of amino acid nitrogen in the finished product of cooking wine is greatly increased on the premise of not sacrificing safety and flavor, and the quality of the finished product of cooking wine is improved. And thus, the preserved fruit has stronger delicate flavor and higher nutritional value.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and more specifically to a method for preparing grain-brewed cooking wine with high amino acid nitrogen content and the method thereof. Background Technology

[0002] Cooking wine, a traditional culinary condiment, primarily functions to remove fishy odors, enhance aroma, and improve umami, effectively elevating the overall flavor and quality of dishes. Grain-brewed cooking wine is a liquid seasoning made primarily from grains such as rice and wheat, using a process involving koji making, saccharification, and fermentation to create a base spirit. Edible salt (and optionally, plant spices, caramel coloring, etc.) is then added. Its flavor originates from the rich metabolic byproducts produced during the brewing process, resulting in a mellow taste and a unique fermented aroma. In recent years, with rising consumer demand for healthy, natural, and high-quality foods, as well as a resurgence of traditional culinary values, the market demand for high-quality grain-brewed cooking wine has continued to climb.

[0003] Among the many indicators used to measure the quality of grain-brewed cooking wine, amino acid nitrogen content has increasingly become one of the key indicators. Amino acid nitrogen mainly originates from the enzymatic hydrolysis and microbial metabolism of raw material proteins during the brewing process, and its content directly reflects the richness of flavor-enhancing amino acids (such as glutamic acid and aspartic acid) in the cooking wine. A higher amino acid nitrogen content not only means that the cooking wine has a more delicious flavor and a richer, fuller taste, but also suggests that it contains more amino acid nutrients, better meeting consumers' pursuit of a high-quality cooking experience that combines deliciousness and health.

[0004] Despite clear market demand, there is generally significant room for improvement in the amino acid nitrogen content of existing grain-brewed cooking wine products on the market. Traditional preparation methods face significant technical bottlenecks in achieving high amino acid nitrogen content, mainly in the following two aspects:

[0005] First, there are inherent limitations in the raw materials. Traditional processes mainly rely on grains such as rice and wheat as protein sources. However, the protein content of these grains is relatively limited. For example, the protein content of rice is generally around 7%-8%. The insufficient total protein in the raw materials fundamentally restricts the potential upper limit of its conversion into amino acid nitrogen during subsequent brewing, thus creating a "ceiling" for increasing the amino acid nitrogen content of the final product.

[0006] Secondly, there are limitations imposed by traditional brewing techniques. Theoretically, increasing amino acid nitrogen content could be achieved by extending the fermentation cycle, allowing for more efficient protease activity and microbial metabolism. However, in practice, this method faces significant challenges. The base spirit produced using traditional methods typically has an alcohol content of only around 15% vol. Prolonged post-fermentation or aging at this alcohol level easily leads to the proliferation of unwanted microorganisms, abnormal fermentation, and a continuous increase in total acid content, resulting in flavor degradation and even food safety risks such as spoilage. Therefore, the traditional approach of simply extending the production cycle to increase amino acid nitrogen content has insurmountable drawbacks in terms of process stability and product safety.

[0007] In summary, the market urgently needs a grain-based brewing liquor and its preparation method that can effectively overcome the limitations of raw materials and processes, significantly increase the amino acid nitrogen content while ensuring product safety and flavor stability. (Invention Content)

[0008] In view of this, the present invention develops a method for preparing grain-brewed wine with high amino acid nitrogen content and the method thereof, which significantly increases the amino acid nitrogen content in grain-brewed wine while ensuring product safety and flavor stability.

[0009] The primary objective of this application is to provide a method for preparing grain-brewed cooking wine with high amino acid nitrogen content, comprising the following steps:

[0010] (1) Preparation of soybean koji: Wheat and / or rice are stir-fried with hot air; cooled to below 45°C, crushed and sieved to obtain grain powder; soybeans are soaked in water and then steamed to obtain cooked soybeans; the cooked soybeans are cooled to below 38°C and mixed with the grain powder at a weight ratio of 1:0-20, and inoculated with koji to obtain mixed koji material; the mixed koji material is fermented at 25-35°C for 40-45 hours to obtain finished koji.

[0011] (2) Preparation of mash: Rice, corn and / or wheat are ground into 50-mesh fine powder, and 1.6-4 times the amount of water is added for liquefaction and saccharification to obtain saccharified liquid;

[0012] Cool the saccharification liquid to 25-30℃, add alcohol yeast and 0-10% of the koji obtained in step (1) for fermentation, and obtain a primary fermentation mash with an alcohol content of 10-18% vol.

[0013] Add water to adjust the alcohol content of the primary fermentation mash to 8-10% vol and cool it to 10-15℃; mix the koji obtained in step (1) with the adjusted 8-10% vol fermentation mash at a mass ratio of 1:2-10, ferment, and obtain secondary fermentation mash;

[0014] The 10-18% vol primary fermentation mash is distilled to obtain an alcoholic liquid; the alcoholic liquid is mixed with the secondary fermentation mash, the alcohol content of the mixed fermentation mash is adjusted to 22-28% vol, and post-fermentation is carried out at this alcohol content;

[0015] After pressing and fermentation, the fermented mash is used to obtain rice wine with an alcohol content of 20-27% vol; the rice wine is then aged and matured.

[0016] (3) Preparation of cooking wine: Spices are placed in the yellow wine obtained after aging in step (2) to extract cooking wine liquid; according to product requirements, water is added to the cooking wine liquid to adjust the alcohol content, and after filtration, ultra-high temperature instantaneous sterilization, cooling and bottling, the grain-brewed cooking wine with high amino acid nitrogen content is obtained.

[0017] As a preferred technical solution, in step (1), the hot air temperature for hot air frying is 270-330℃, and the frying time is 90-200s; the crushing and sieving is crushing through a 32-mesh sieve.

[0018] As a preferred technical solution, in step (1), the soaking time is 4-12h; the cooking conditions are as follows: cook under a pressure of 0.10-0.15MPa for 1-5min; the inoculum is Aspergillus oryzae spore powder, and the inoculation amount is 0.03-0.05% of the total mass of cereal flour and soybeans.

[0019] As a preferred technical solution, the liquefaction and saccharification process in step (2) is as follows: add 1‰ of the total mass of the raw materials for saccharification solution to amylase, liquefy for 20-30 minutes at a liquefaction temperature of 95-100℃; then cool down to 55-60℃, add saccharifying enzyme according to 100-120U per gram of raw materials for saccharification solution, saccharify for 1 hour, cool down to below 40℃, add 1‰ of the total mass of the raw materials for saccharification solution to acidic protease and 1‰ of the total mass of the raw materials for saccharification solution to compound clarifying enzyme, and mix evenly to obtain saccharification solution.

[0020] As a preferred technical solution, the composite clarifying enzyme includes glucanase, xylanase and cellulase; the addition ratio is 0.6‰ of glucanase, 0.3‰ of xylanase and 0.1‰ of cellulase.

[0021] As a preferred technical solution, in step (2), the amount of alcohol yeast added is 1‰ of the total mass of the raw materials for preparing the saccharification liquid, and the amount of yeast used to form the starter culture is 0%-15% of the total mass of the raw materials for preparing the saccharification liquid; the alcohol yeast is added after being activated in 5% saccharification liquid at 28°C for 1 hour; the fermentation time for preparing the primary fermentation mash is 10-20 days, and the fermentation temperature is 25-30°C; the fermentation time for preparing the secondary fermentation mash is 15-35 days, and the fermentation temperature is 10-15°C.

[0022] As a preferred technical solution, the alcohol content of the alcohol liquid in step (2) is 90% vol; the mixing mass ratio of the alcohol liquid to the secondary fermentation mash is 1:3-8; the temperature of the post-fermentation is room temperature, and the post-fermentation time is 45-90 days.

[0023] As a preferred technical solution, the pressing conditions in step (2) are as follows: pressure 0.5 MPa, filtration time 16 hours, temperature room temperature; the aging and maturation operation is as follows: the rice wine is heated to 121℃ for 3-5 seconds, then cooled to below 40℃ and placed at room temperature for natural placement; the aging and maturation time is ≥6 months.

[0024] As a preferred technical solution, the extraction time in step (3) is 10-90 days.

[0025] Another object of this application is to provide a grain-brewed cooking wine with high amino acid nitrogen content prepared by the above-described method.

[0026] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0027] The technical solution of this invention achieves significant technical effects through innovative raw material ratios and systematic optimization of multi-stage fermentation processes, specifically in the following aspects:

[0028] 1. Significantly improves core indicator (amino acid nitrogen content)

[0029] By employing a complex grain raw material system (such as rice, wheat, and soybeans), and utilizing the complementary amino acid composition of different grain proteins, a richer and more balanced protein substrate is provided for the brewing process. Combined with an extended fermentation cycle and segmented controlled fermentation, favorable conditions are created for the full action of proteases, greatly promoting the conversion of proteins into peptides and free amino acids. This synergistic effect fundamentally breaks through the bottlenecks of traditional processes, resulting in a significant and stable increase in the amino acid nitrogen content of the final product, far exceeding the standards of ordinary rice wine and cooking wine.

[0030] 2. Effectively resolves the contradictions in traditional processes (prolonged fermentation versus safety).

[0031] Traditional fermentation processes often lead to spoilage due to prolonged fermentation. This invention innovatively introduces a "semi-simulated fermentation" stage with high alcohol concentration, where the alcohol content of the fermentation mash is adjusted and maintained at a high level (e.g., 22-28% vol) in the later stages. This measure creates an environment that inhibits the growth of unwanted microorganisms without interrupting biochemical reactions (such as protease activity), thus successfully resolving the traditional contradiction between "extending the fermentation period to enhance flavor and preventing spoilage," ensuring product safety and pure flavor.

[0032] 3. Optimize the overall quality and flavor of the product.

[0033] The flavor is richer and more mellow: multi-stage fermentation (initial fermentation, secondary low-temperature fermentation, and high-concentration post-fermentation) makes the biochemical reactions such as saccharification, yeast fermentation, and esterification more distinct and complete, generating more complex flavor substances.

[0034] Improved stability and clarity: The fine separation technology of plate and frame filtration combined with diatomaceous earth filtration effectively removes suspended impurities and large molecular proteins from the wine, improving the physical stability and sensory clarity of the product.

[0035] Shelf life guarantee: The final product is sterilized using ultra-high temperature (UHT) technology, which processes the product at 121°C for only 3-8 seconds. This process effectively kills microorganisms while preserving flavor and nutrients to the maximum extent, ensuring the product's commercial sterility and extending its shelf life.

[0036] 4. Improve process controllability and production efficiency

[0037] The process parameters are clear and controllable: key parameters such as temperature, time, and alcohol content at each fermentation stage have been precisely defined (e.g., initial fermentation 10-20 days, 25-30℃; secondary low-temperature fermentation 10-15℃, etc.), which improves the repeatability and standardization of the process.

[0038] Promotes uniform reaction: Intermittent stirring is used during fermentation, which enhances mass transfer efficiency, ensures the uniformity of the fermentation system, and makes microbial metabolism and enzymatic hydrolysis more uniform and thorough.

[0039] In summary, this invention, through a systematic and innovative solution, significantly enhances the core nutritional value (amino acid nitrogen) of grain-brewed cooking wine while effectively ensuring product safety, flavor richness, and storage stability, providing an efficient and controllable technical path for producing high-quality brewed cooking wine. Detailed Implementation

[0040] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] Example 1

[0042] A method for preparing a grain-brewed cooking wine with high amino acid nitrogen content includes the following steps:

[0043] (1) Preparation of fermented soybean koji:

[0044] Prepare rice, wheat, and soybeans in a mass ratio of 2.5:2.5:5. Mix the rice and wheat and roast them in hot air at 300℃ for 90 seconds. After roasting, cool to below 45℃, crush, and pass through a 32-mesh sieve to obtain grain flour, of which 25% is fine powder passing through the sieve. Soak soybeans in water at a mass ratio of 1:2 for 4 hours, then cook at a pressure of 0.12 MPa for 2 minutes to obtain cooked soybeans. Cool the cooked soybeans to below 38℃ and mix them with the grain flour in a 1:1 weight ratio, and inoculate with koji (Aspergillus oryzae spore powder) at an inoculation amount of 0.03% (based on the mass of the mixed koji). Cook the mixed koji at 25℃ for 40 hours to obtain the finished koji.

[0045] (2) Preparation of mash:

[0046] Rice was ground into a 50-mesh fine powder and used as the raw material for primary fermentation. 2.2 times the amount of water (by weight of the raw material) was added, along with 1‰ of the total mass of the raw material for saccharification. The mixture was liquefied for 20 minutes at 95°C. Then, the temperature was lowered to 55°C, and saccharifying enzyme was added at a ratio of 100U / gram of raw material prepared from the saccharification solution. Saccharification was continued for 1 hour, and the temperature was lowered to below 40°C. Acidic protease (1‰ of the total mass of the raw material prepared from the saccharification solution) and a complex clarifying enzyme mixture (0.6‰ of dextranase, 0.3‰ of xylanase, and 0.1‰ of cellulase) (also 1‰ of the total mass of the raw material prepared from the saccharification solution) were added and mixed thoroughly to obtain the saccharification solution. The saccharification liquid was cooled to 25°C, and alcohol yeast (yellow wine yeast, Hu Niang 2.091, purchased from Angel Yeast Co., Ltd.) of 1‰ of the total mass of the raw materials for saccharification liquid preparation was added (the alcohol yeast was first activated in 5% saccharification liquid at 28°C for 1 hour) and 0.05% of the total mass of the raw materials for saccharification liquid preparation in step (1) was formed into koji. Fermentation was carried out at 25°C for 10 days to obtain a primary fermented mash with an alcohol content of 14% vol. Water was added to adjust the alcohol content of the primary fermented mash to 8% vol, and the temperature was lowered to 10°C. The koji obtained in step (1) and the adjusted fermented mash were mixed at a mass ratio of 1:2.5 (i.e., the koji addition ratio for secondary fermentation was 0.4), and fermented at 10°C for 15 days to obtain a secondary fermented mash. The primary fermented mash (alcohol content 14% vol) was distilled to obtain an alcoholic liquid of 90% vol. The alcoholic liquid was mixed with the secondary fermentation mash to bring the alcohol content of the mixed fermentation mash to 22% vol, and then subjected to post-fermentation at room temperature for 45 days. After post-fermentation, the mash was pressed for 16 hours at a pressure of 0.5 MPa and room temperature to obtain rice wine with an alcohol content of 20% vol. The rice wine was then heated to 121℃ for 5 seconds, cooled to below 40℃, and then naturally aged at room temperature for 6 months.

[0047] (3) Preparation of cooking wine:

[0048] Spices (star anise, fennel, Sichuan peppercorns, cloves, cinnamon, scallions, and ginger, the proportions can be adjusted according to the type of cooking wine) are infused in aged Shaoxing wine for 10 days to obtain the cooking wine liquid. An appropriate amount of water is added to the cooking wine liquid to adjust the alcohol content to the standard requirement (minimum ≥10% vol, depending on the quality grade). The liquid is then filtered, sterilized at ultra-high temperature (121℃, 5 seconds), cooled, and bottled to obtain a grain-brewed cooking wine with high amino acid nitrogen content. The finished product has an amino acid nitrogen content of 1.26 g / L, exhibiting a typical complex grain aroma and fermented wine aroma, with a mellow and harmonious fragrance, free of astringency or off-flavors.

[0049] Example 2

[0050] A method for preparing a grain-brewed cooking wine with high amino acid nitrogen content includes the following steps:

[0051] (1) Preparation of fermented soybean koji:

[0052] Prepare rice and soybeans in a 5:5 weight ratio. Stir-fry the rice in hot air at 300℃ for 90 seconds. After stir-frying, cool to below 45℃, crush, and pass through a 32-mesh sieve to obtain grain flour, of which 30% is fine powder passing through the sieve. Soak soybeans in water at a 1:2 weight ratio for 8 hours, then cook at a pressure of 0.12 MPa for 2 minutes to obtain cooked soybeans. Cool the cooked soybeans to below 38℃ and mix with the grain flour in a 1:1 weight ratio. Inoculate with koji (Aspergillus oryzae spore powder) at a rate of 0.04% (based on the weight of the mixed koji). Cook the mixed koji at 28℃ for 42 hours to obtain the finished koji.

[0053] (2) Preparation of mash:

[0054] Wheat was ground to a fine powder of 50 mesh and used as the raw material for primary fermentation. 2.0 times the amount of water (by weight of the raw material) was added, along with 1‰ of the total mass of the raw material to be saccharified. The mixture was liquefied for 30 minutes at 98℃. Then, the temperature was lowered to 58℃, and saccharifying enzyme was added at a ratio of 120U per gram of raw material prepared from the saccharified solution. Saccharification was continued for 1 hour, and the temperature was lowered to below 40℃. Acidic protease (1‰ of the total mass of the raw material prepared from the saccharified solution) and a complex clarifying enzyme mixture (0.6‰ of dextranase, 0.3‰ of xylanase, and 0.1‰ of cellulase) (1‰ of the total mass of the raw material prepared from the saccharified solution) were added and mixed thoroughly to obtain the saccharified solution. The saccharification liquid was cooled to 28°C, and 1‰ of the total mass of the raw materials for saccharification liquid preparation (yellow wine yeast, AS2.1392, purchased from Angel Yeast Co., Ltd.) (activation method same as in Example 1) and 0.08% of the total mass of the raw materials for saccharification liquid preparation were added to form the koji in step (1). Fermentation was carried out at 28°C for 15 days to obtain a primary fermented mash with an alcohol content of 14.5% vol. Water was added to adjust the alcohol content of the primary fermented mash to 9% vol, and the temperature was lowered to 12.5°C. The koji obtained in step (1) and the adjusted fermented mash were mixed at a mass ratio of 1:3.33 (i.e., the koji addition ratio for secondary fermentation was 0.3), and fermented at 12.5°C for 20 days to obtain a secondary fermented mash. The primary fermented mash (alcohol content 14.5% vol) was distilled to obtain an alcoholic liquid of 90% vol. The alcoholic liquid was mixed with the secondary fermentation mash to bring the alcohol content of the mixed fermentation mash to 24% vol, and then subjected to post-fermentation at room temperature for 60 days. After post-fermentation, the pressing conditions were the same as in Example 1, yielding rice wine with an alcohol content of 22% vol. The rice wine was then heated to 121°C for 5 seconds, cooled to below 40°C, and naturally aged at room temperature for 9 months.

[0055] (3) Preparation of cooking wine:

[0056] Spices (star anise, fennel, Sichuan peppercorns, cloves, cinnamon, scallions, and ginger; the proportions can be adjusted according to the type of cooking wine) are infused in aged Shaoxing wine for 20 days to obtain the cooking wine liquid. An appropriate amount of water is added to the cooking wine liquid to adjust the alcohol content to the standard requirement (according to different quality grades, a minimum of ≥10% vol; the standard requirement for cooking wine is an alcohol content ≥10°, so the alcohol content adjustment here is based on product requirements, with a minimum of 10°). Then, the mixture is filtered, subjected to ultra-high temperature instantaneous sterilization (121℃, 5 seconds), cooled, and bottled to obtain a grain-brewed cooking wine with a high amino acid nitrogen content. The finished product has an amino acid nitrogen content of 1.01 g / L and exhibits good flavor and taste.

[0057] Example 3

[0058] A method for preparing a grain-brewed cooking wine with high amino acid nitrogen content includes the following steps:

[0059] (1) Preparation of fermented soybean koji:

[0060] Prepare wheat and soybeans in a 6:4 mass ratio. Roast the wheat in hot air at 300℃ for 90 seconds. After roasting, cool to below 45℃, crush, and pass through a 32-mesh sieve to obtain grain flour, of which 25% is fine powder passing through the sieve. Soak the soybeans in water at a 1:2 mass ratio for 12 hours, then cook at a pressure of 0.12 MPa for 2 minutes to obtain cooked soybeans. Cool the cooked soybeans to below 38℃ and mix with the grain flour in a 4:6 weight ratio, then inoculate with 0.05% (based on the mass of the mixed koji) of Aspergillus oryzae spore powder. Cook the mixed koji at 35℃ for 45 hours to obtain the finished koji.

[0061] (2) Preparation of mash:

[0062] Rice and wheat were mixed in a 50:50 mass ratio and ground into a 50-mesh fine powder as the primary fermentation raw material. 1.8 times the volume of water (based on the raw material mass ratio) was added, along with 1‰ of the total mass of the raw material to be saccharified. The mixture was liquefied for 25 minutes at 100℃. Then, the temperature was lowered to 60℃, and saccharifying enzyme was added at a ratio of 110U per gram of raw material prepared from the saccharified solution. Saccharification was continued for 1 hour, and the temperature was lowered to below 40℃. Acidic protease (1‰ of the total mass of the raw material prepared from the saccharified solution) and a complex clarifying enzyme mixture (0.6‰ glucanase, 0.3‰ xylanase, and 0.1‰ cellulase) (1‰ of the total mass of the raw material prepared from the saccharified solution) were added and mixed thoroughly to obtain the saccharified solution. The saccharification liquid was cooled to 30°C, and 1‰ of the total mass of the raw materials for saccharification liquid preparation (yellow wine yeast, Hu Niang 2.091, purchased from Angel Yeast Co., Ltd.) (activation method same as in Example 1) and 1.4% of the total mass of the raw materials for saccharification liquid preparation were added to form the koji in step (1). Fermentation was carried out at 30°C for 20 days to obtain a primary fermented mash with an alcohol content of 15.5% vol. Water was added to adjust the alcohol content of the primary fermented mash to 10% vol, and the temperature was lowered to 15°C. The koji obtained in step (1) and the adjusted fermented mash were mixed at a mass ratio of 1:5 (i.e., the koji addition ratio for secondary fermentation was 0.2), and fermented at 15°C for 25 days to obtain a secondary fermented mash. The primary fermented mash (alcohol content 15.5% vol) was distilled to obtain an alcoholic liquid of 90% vol. This alcoholic liquid was mixed with the secondary fermented mash to make the alcohol content of the mixed fermented mash reach 28% vol, and post-fermentation was carried out at room temperature for 75 days. After the post-fermentation process, the pressing conditions were the same as in Example 1, yielding a rice wine with an alcohol content of 27% vol. The rice wine was then heated to 121°C for 5 seconds, cooled to below 40°C, and naturally aged at room temperature for 12 months.

[0063] (3) Preparation of cooking wine:

[0064] Spices (star anise, fennel, Sichuan peppercorns, cloves, cinnamon, scallions, and ginger, the proportions can be adjusted according to the type of cooking wine) are infused in aged Shaoxing wine for 30 days to obtain the cooking wine liquid. An appropriate amount of water is added to the cooking wine liquid to adjust the alcohol content to the standard requirement (minimum ≥10% vol, depending on the quality grade). The liquid is then filtered, sterilized at ultra-high temperature (121℃, 5 seconds), cooled, and bottled to obtain a grain-brewed cooking wine with high amino acid nitrogen content. The finished product has an amino acid nitrogen content of 1.15 g / L and exhibits good flavor and taste.

[0065] Example 4

[0066] A method for preparing a grain-brewed cooking wine with high amino acid nitrogen content includes the following steps:

[0067] (1) Preparation of fermented soybean koji:

[0068] Soak soybeans in water at a soybean-to-water ratio of 1:2 for 12 hours, then cook them at a pressure of 0.12 MPa for 2 minutes to obtain cooked soybeans. Cool the cooked soybeans to below 38℃ and inoculate them with koji (Aspergillus oryzae spore powder) at a rate of 0.05% (based on the koji mass). Cook the koji at 35℃ for 43 hours to obtain the finished koji.

[0069] (2) Preparation of mash:

[0070] Corn and wheat were mixed at a mass ratio of 20:80 and ground into a 50-mesh fine powder as the primary fermentation raw material. 1.8 times the volume of water (based on the raw material mass ratio) was added, along with 1‰ of the total mass of the raw material to be saccharified. The mixture was liquefied for 25 minutes at 100℃. Then, the temperature was lowered to 58℃, and saccharifying enzyme was added at a ratio of 110U per gram of raw material prepared from the saccharified solution. Saccharification was continued for 1 hour, and the temperature was lowered to below 40℃. Acidic protease and a complex clarifying enzyme (0.6‰ glucanase, 0.3‰ xylanase, and 0.1‰ cellulase) were added at 1‰ of the total mass of the raw material prepared from the saccharified solution, and mixed thoroughly to obtain the saccharified solution. The saccharification liquid was cooled to 30°C, and 1‰ of the total mass of the raw materials for saccharification liquid preparation, alcohol yeast (yellow wine yeast, AS2.1392, purchased from Angel Yeast Co., Ltd.) (activation method same as in Example 1) and 5% of the total mass of the raw materials for saccharification liquid preparation were added to form the koji in step (1). Fermentation was carried out at 30°C for 20 days to obtain a primary fermented mash with an alcohol content of 15% vol. Water was added to adjust the alcohol content of the primary fermented mash to 10% vol, and the temperature was lowered to 15°C. The koji obtained in step (1) and the adjusted fermented mash were mixed at a mass ratio of 1:5 (i.e., the koji addition ratio for secondary fermentation was 0.2), and fermented at 15°C for 25 days to obtain a secondary fermented mash. The primary fermented mash (alcohol content 15% vol) was distilled to obtain an alcoholic liquid of 90% vol. This alcoholic liquid was mixed with the secondary fermented mash to bring the alcohol content of the mixed fermented mash to 28% vol, and post-fermentation was carried out at room temperature for 75 days. After the post-fermentation process, the pressing conditions were the same as in Example 1, yielding a rice wine with an alcohol content of 27% vol. The rice wine was then heated to 121°C for 5 seconds, cooled to below 40°C, and naturally aged at room temperature for 12 months.

[0071] (3) Preparation of cooking wine:

[0072] Spices (star anise, fennel, Sichuan peppercorns, cloves, cinnamon, scallions, and ginger, the proportions can be adjusted according to the type of cooking wine) are infused in aged Shaoxing wine for 30 days to obtain the cooking wine liquid. An appropriate amount of water is added to the cooking wine liquid to adjust the alcohol content to the standard requirement (minimum ≥10% vol, depending on the quality grade). The liquid is then filtered, sterilized at ultra-high temperature (121℃, 5 seconds), cooled, and bottled to obtain a grain-brewed cooking wine with high amino acid nitrogen content. The finished product has an amino acid nitrogen content of 2.05 g / L and exhibits good flavor and taste.

[0073] Example 5

[0074] A method for preparing a grain-brewed cooking wine with high amino acid nitrogen content includes the following steps:

[0075] (1) Preparation of fermented soybean koji:

[0076] Prepare rice, wheat, and soybeans in a mass ratio of 2.5:2.5:5. Mix the rice and wheat and roast them in hot air at 300℃ for 90 seconds. After roasting, cool to below 45℃, crush, and pass through a 32-mesh sieve to obtain grain flour, of which 25% is fine powder passing through the sieve. Soak soybeans in water at a mass ratio of 1:2 for 4 hours, then cook at a pressure of 0.12 MPa for 2 minutes to obtain cooked soybeans. Cool the cooked soybeans to below 38℃ and mix them with the grain flour in a 1:1 weight ratio, and inoculate with koji (Aspergillus oryzae spore powder) at an inoculation amount of 0.03% (based on the mass of the mixed koji). Cook the mixed koji at 25℃ for 40 hours to obtain the finished koji.

[0077] (2) Preparation of mash:

[0078] Rice and corn were ground into 50-mesh fine powder at an 8:2 ratio to serve as the primary fermentation raw materials. 2.2 times the amount of water (by weight of the raw materials) was added, along with 1‰ of the total mass of the raw materials for saccharification. The mixture was liquefied for 22 minutes at 95°C. Then, the temperature was lowered to 55°C, and saccharifying enzyme was added at a ratio of 115U per gram of raw materials prepared from the saccharification solution. Saccharification was continued for 1 hour, and the temperature was lowered to below 40°C. Acidic protease (1‰ of the total mass of the raw materials prepared from the saccharification solution) and a complex clarifying enzyme mixture (0.6‰ glucanase, 0.3‰ xylanase, and 0.1‰ cellulase) (1‰ of the total mass of the raw materials prepared from the saccharification solution) were added and mixed thoroughly to obtain the saccharification solution. The saccharification liquid was cooled to 25°C, and 1‰ of the total mass of the raw materials for preparing the saccharification liquid was added to produce alcoholic yeast (yellow wine yeast, AS2.1392, purchased from Angel Yeast Co., Ltd.) (the alcoholic yeast was first activated in 5% saccharification liquid at 28°C for 1 hour). Fermentation was carried out at 25°C for 15 days to obtain a primary fermentation mash with an alcohol content of 13.5% vol. Water was added to adjust the alcohol content of the primary fermentation mash to 8% vol, and the temperature was lowered to 10°C. The koji obtained in step (1) was mixed with the adjusted fermentation mash at a mass ratio of 1:2.5 (i.e., the koji addition ratio for secondary fermentation was 0.4), and fermented at 10°C for 15 days to obtain a secondary fermentation mash. The primary fermentation mash (alcohol content 13.5% vol) was distilled to obtain an alcoholic liquid of 90% vol. This alcoholic liquid was mixed with the secondary fermentation mash to bring the alcohol content of the mixed fermentation mash to 22% vol, and post-fermentation was carried out at room temperature for 45 days. After the post-fermentation process, the rice wine is pressed for 16 hours at a pressure of 0.5 MPa and room temperature to obtain rice wine with an alcohol content of 20% vol. The rice wine is then heated to 121℃ for 5 seconds, cooled to below 40℃, and naturally aged at room temperature for 6 months.

[0079] (3) Preparation of cooking wine:

[0080] Spices (star anise, fennel, Sichuan peppercorns, cloves, cinnamon, scallions, and ginger, the proportions can be adjusted according to the type of cooking wine) are infused in aged Shaoxing wine for 10 days to obtain cooking wine liquid. An appropriate amount of water is added to the cooking wine liquid to adjust the alcohol content to the standard requirement (minimum ≥10% vol, depending on the quality grade). The liquid is then filtered, sterilized at ultra-high temperature (121℃, 5 seconds), cooled, and bottled to obtain a grain-brewed cooking wine with high amino acid nitrogen content. The finished product has an amino acid nitrogen content of 1.30 g / L, exhibiting a typical complex grain aroma and fermented wine aroma, with a mellow and harmonious fragrance, free of astringency or off-flavors.

[0081] Conventional cooking wine preparation process:

[0082] Process 1: Soak rice in water for 1-3 days, then drain and steam. Cool the steamed rice and add yeast for saccharification for 2-3 days. After saccharification, add process water and 5-10% raw wheat koji in a 1:2 ratio for fermentation. The fermentation cycle is 15-35 days.

[0083] The fermented mash is pressed to obtain raw rice wine. The raw rice wine is then sterilized and stored in jars or pumped into large tanks for aging. During this stage, the alcohol content is 14.5-16.0% vol and the amino acid nitrogen content is 0.4-0.8 g / L.

[0084] The aged rice wine was blended by adding spice extract, edible salt, and process water, and the alcohol content was adjusted to meet the standard requirements for seasoning wine (≥10.0% vol), with amino acid nitrogen content of 0.4-0.6 g / L.

[0085] Process 2: Purchase 95% vol edible alcohol, add process water, edible salt, spices, etc., with or without adding the rice wine produced in Process 1, adjust the indicators to meet the standards for seasoning wine, with an alcohol content ≥10.0% vol, and add monosodium glutamate, etc. to increase the amino acid nitrogen content to ≥0.2 g / L.

[0086] Table 1. Comparison of effects between conventional cooking wine and this patented cooking wine

[0087] project SB / T10416-2007 Standard Requirements for Seasoning Wine Standard cooking wine (process 2) Standard cooking wine (process 1) Example 1 Example 2 Example 3 Example 4 Example 5 Amino acid nitrogen (as nitrogen) / (g / L) ≥0.2 0.28 0.35 1.26 1.01 1.15 2.05 1.30 Alcohol content (20℃) / %vol ≥10.0 10.8 11.0 12.5 11.0 15.0 16.0 12

[0088] The results analysis, as shown in Table 1, indicate that the amino acid nitrogen content of the cooking wine prepared in the embodiments of this application is significantly higher than that of the conventional cooking wine group, and the alcohol content is also relatively higher.

[0089] Control group 1: No low-temperature fermentation

[0090] Preparation of fermented soybean koji:

[0091] Prepare wheat and soybeans in a 6:4 mass ratio. Roast the wheat in hot air at 300℃ for 90 seconds. After roasting, cool to below 45℃, crush, and pass through a 32-mesh sieve to obtain grain flour, of which 25% is fine powder passing through the sieve. Soak the soybeans in water at a 1:2 mass ratio for 12 hours, then cook at a pressure of 0.12 MPa for 2 minutes to obtain cooked soybeans. Cool the cooked soybeans to below 38℃ and mix with the grain flour in a 4:6 weight ratio, then inoculate with 0.05% (based on the mass of the mixed koji) of Aspergillus oryzae spore powder. Cook the mixed koji at 35℃ for 45 hours to obtain the finished koji.

[0092] (2) Preparation of mash:

[0093] Rice and wheat were mixed in a 50:50 mass ratio and ground into a 50-mesh fine powder as the raw material for primary fermentation. 1.8 times the amount of water (based on the mass ratio of the raw material) was added, and amylase was added and liquefied at 100°C. The mixture was then cooled to 60°C, and saccharifying enzyme was added. Saccharification was carried out for 1 hour, and other enzyme preparations were added when the temperature dropped below 40°C to obtain a saccharified liquid. The saccharified liquid was cooled to 30°C, and alcohol yeast (yellow wine yeast, AS2.1392, purchased from Angel Yeast Co., Ltd.) (activation method same as in Example 1) and 1.4% of the koji obtained in step (1) (based on the mass of the saccharified liquid) were added for fermentation at 30°C for 20 days to obtain a primary fermented mash with an alcohol content of 18% vol. Water was added to adjust the alcohol content of the primary fermented mash to 10% vol, and the temperature was lowered to 15°C. The koji obtained in step (1) was mixed with the adjusted fermented mash at a mass ratio of 1:5 (i.e., the koji addition ratio for secondary fermentation was 0.2). The mash was fermented at room temperature of 28℃ for 25 days to obtain secondary fermented mash with an alcohol content of 12%vol, which is much lower than that of low-temperature fermentation. It also had white spots on the surface (microbial contamination), off-odors, and a total acidity of 15 g / L, indicating fermentation failure.

[0094] Control group 2: No high-alcohol post-ripening (i.e., no addition of 90% vol alcohol).

[0095] (1) Preparation of wheat koji: Wheat is pressed into wheat flakes, 60% water is added, and the mixture is steamed after being evenly mixed; the cooked wheat flakes are cooled to below 38°C and inoculated with Aspergillus oryzae spore powder at an inoculation amount of 0.03% (based on the mass of wheat raw materials) to obtain mixed koji material; the mixed koji material is fermented at 25-35°C for 40-45 hours to obtain finished koji.

[0096] (2) Preparation of mash: Rice, corn and / or wheat are ground into 50-mesh fine powder, and 1.6-2.5 times the amount of water is added for liquefaction and saccharification to obtain saccharified liquid;

[0097] Cool the saccharification liquid to 25-30℃, add alcohol yeast (yellow wine yeast, AS2.1392, purchased from Angel Yeast Co., Ltd.) and 0-10% of the koji obtained in step (1) for fermentation to obtain fermented mash with an alcohol content of 14-18%vol.

[0098] Press the fermented mash after the above fermentation is completed to obtain rice wine with an alcohol content of 14-18% vol;

[0099] The food-grade aseptic stainless steel tank is cleaned and sterilized to maintain a sterile state. The rice wine is then sterilized at 85°C and pumped into a large food-grade aseptic stainless steel storage tank to ensure that the temperature of the rice wine is ≥65°C after entering the tank. The rice wine is then aged and matured after naturally cooling to room temperature in the storage tank.

[0100] The aging process requires high sterility of equipment and pipelines, and involves significant investment in equipment. If conventional non-sterile storage tanks are used, quality problems such as contamination by bacteria, increased total acidity, and cloudiness of the wine can easily occur within a short period of time, leading to storage failure.

[0101] (3) Preparation of cooking wine: Spices are placed in water and extracted at 85℃-100℃, then filtered to obtain spice liquid; according to product requirements, water, spice liquid, edible salt, etc. are added to the rice wine liquid to adjust the alcohol content, and after filtration, ultra-high temperature instantaneous sterilization, cooling and bottling, the ordinary cooking wine is obtained.

[0102] In summary, control groups 1 and 2 require high levels of equipment sterility; otherwise, prolonged fermentation and aging cannot be achieved. However, this application achieves fermentation and aging without the need for sterile tanks or high equipment sterility. The high-alcohol post-fermentation process of this application plays a crucial role in inhibiting microbial contamination, preventing excessive total acidity, and avoiding turbidity in the wine.

[0103] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0104] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for producing a high amino acid nitrogen content grain brewing liquor, characterized by, The method comprises the following steps: (1) preparation of bean starter: wheat and / or rice is roasted by hot air; after cooling to below 45℃, it is crushed and sieved to obtain grain powder; soybeans are soaked in water and then cooked to obtain cooked soybeans; the cooked soybeans are cooled to below 38℃ and mixed with the grain powder at a weight ratio of 1:0-20, and inoculated with starter to obtain mixed starter material; the mixed starter material is incubated at 25-35℃ for 40-45h to obtain starter; (2) preparation of wine mash: rice, corn and / or wheat are ground into 50-mesh fine powder, 1.6-4 times water is added for liquefaction and saccharification to obtain a saccharification liquid; the saccharification liquid is cooled to 25-30℃, and alcohol yeast and the starter obtained in step (1) are added for fermentation to obtain a primary fermentation mash with an alcohol content of 10-18%vol; water is added to adjust the alcohol content of the primary fermentation mash to 8-10%vol, and the temperature is lowered to 10-15℃; the starter obtained in step (1) is mixed with the adjusted 8-10%vol fermentation mash at a mass ratio of 1:2-10, and fermentation is carried out to obtain a secondary fermentation mash; the 10-18%vol primary fermentation mash is distilled to obtain an alcohol liquid; the alcohol liquid is mixed with the secondary fermentation mash, the alcohol content of the mixed fermentation mash is adjusted to 22-28%vol, and post-ripening fermentation is carried out at this alcohol content; the fermented mash after post-ripening fermentation is pressed to obtain yellow rice wine with an alcohol content of 20-27%vol; the yellow rice wine is aged and ripened; (3) preparation of seasoning wine: spices are immersed in the yellow rice wine obtained after aging and ripening in step (2) to obtain a seasoning wine liquid; according to product requirements, water is added to the seasoning wine liquid to adjust the alcohol content, and after filtration, ultra-high temperature instantaneous sterilization, cooling and filling, the high-amino-acid-state nitrogen content grain-brewed seasoning wine is obtained.

2. The production method according to claim 1, characterized by, In step (1), the hot air roasting temperature is 270-330℃, and the roasting time is 90-200s; the crushing and sieving is crushing and sieving through a 32-mesh sieve.

3. The production method according to claim 1 or 2, characterized by, In step (1), the water soaking time is 4-12h; the cooking conditions are as follows: cooking under a pressure of 0.10-0.15MPa for 1-5min; the starter is Aspergillus oryzae spore powder, and the inoculation amount is 0.03-0.05% of the total mass of grain powder and soybeans.

4. The method of claim 1, wherein, In step (2), the operation process of liquefaction and saccharification is as follows: 1‰ of amylase based on the total mass of saccharification liquid preparation raw materials is added, and liquefaction is carried out at 95-100℃ for 20-30min; then the temperature is lowered to 55-60℃, 100-120U of saccharifying enzyme per gram of saccharification liquid preparation raw materials is added, and saccharification is carried out for 1h; the temperature is lowered to below 40℃, 1‰ of acid protease based on the total mass of saccharification liquid preparation raw materials is added, and the mixture is uniformly mixed to obtain a saccharification liquid.

5. The preparation method according to claim 4, characterized in that, The compound clarifying enzyme comprises glucanase, xylanase and cellulase; the addition ratio is 0.6‰ of glucanase, 0.3‰ of xylanase and 0.1‰ of cellulase.

6. The method of claim 1, wherein, The amount of alcohol yeast in step (2) is 1‰ of the total mass of raw materials for preparing the saccharification liquid, and the amount of koji is 0-15% of the total mass of raw materials for preparing the saccharification liquid; the alcohol yeast is activated in 5% saccharification liquid at 28℃ for 1 hour before being added; the fermentation time for preparing the primary fermentation mash is 10-20 days, and the fermentation temperature is 25-30℃; the fermentation time for preparing the secondary fermentation mash is 15-35 days, and the fermentation temperature is 10-15℃.

7. The preparation method according to claim 1, characterized in that, The alcohol content of the alcohol liquid in step (2) is 90%vol; the mass ratio of the alcohol liquid to the secondary fermentation mash is 1:3-8; the temperature for the post-ripening fermentation is room temperature, and the time for the post-ripening fermentation is 45-90 days.

8. The method of claim 1, wherein, The pressing conditions in step (2) are as follows: pressure 0.5Mpa, pressure filtration time 16 hours, and temperature normal temperature; the operation for the aging post-ripening is as follows: the yellow rice wine is heated at 121℃ for 3-5 seconds, then cooled to below 40℃, and then naturally placed at room temperature; the time for the aging post-ripening is ≥6 months.

9. The method of claim 1, wherein, The time for the leaching in step (3) is 10-90 days. 10.A high-amino-acid-nitrogen-content grain brewing cooking wine prepared by the preparation method in any one of claims 1-9.