Production process and quality control method of solid-state method Daqu Fen-flavor mung bean liquor

Abstract

According to the production process and the quality control method of the solid-state-method Daqu Fen-flavor mung bean liquor, key process parameters such as raw material pretreatment, grain steaming, inoculation and bacterium cultivation, fermentation in a cellar, distillation and the like are scientifically controlled, and the problem of particularity of mung beans serving as liquor making raw materials is solved. According to the method, low-temperature presoaking (15-25 DEG C) is adopted for 15 hours, the water suffocating time is determined according to the mung bean variety (the mung beans in northeast China are 15 minutes, and the other mung beans are 10-20 minutes), the koji consumption is 5-8%, the cellar entering temperature is 20-22 DEG C in a cold season, the cellar entering temperature is 25-28 DEG C in a hot season, the fermentation period is 18-20 days, the wine flowing temperature is lower than 20 DEG C and lower than or equal to 23 DEG C, the wine flowing temperature is higher than 20 DEG C and lower than or equal to 28 DEG C, and the wine flowing speed is 2.8-3.2 jin / min. According to the method disclosed by the invention, the retention rate of flavonoid substances is greater than or equal to 85%, the liquor yield is improved to 48-52%, the fermentation period is shortened by 40%, the quality and yield of the mung bean liquor are remarkably improved, and a technical support is provided for industrialization of the mung bean liquor.

Description

Technical Field

[0001] This invention relates to the field of baijiu brewing technology, and in particular to a production process and quality control method for solid-state fermented daqu-based light-aroma mung bean baijiu. It is applicable to baijiu production using mung beans as the main raw material, and is especially suitable for solving the special problems of mung beans as a brewing raw material. Background Technology

[0002] Traditional Baijiu raw material limitations: Currently, Baijiu brewing mainly uses sorghum, rice, wheat and other raw materials, while mung beans are rarely used as a brewing raw material.

[0003] Bottlenecks in mung bean brewing technology: Raw material characteristics: mung bean skin is relatively thick (average thickness 0.15-0.25mm), and starch structure is special (amylose content 45-55%, amylopectin content 45-55%), which is difficult to effectively handle with traditional brewing processes (refer to Food Science, Vol. 41, No. 5, 2020).

[0004] Missing process parameters: Existing literature lacks guidance on key process parameters for mung beans, such as soaking, steaming, and fermentation. It only covers mung bean beverages and does not cover baijiu brewing. It does not address key issues in baijiu production. While the production process of mung bean wine is described, key parameters are not optimized for the characteristics of mung beans, and core issues such as "soaking time" are not addressed.

[0005] Unstable quality: Existing mung bean wine products suffer from problems such as monotonous flavor, rough taste, and low alcohol yield (42-45%).

[0006] The shortcomings of existing technology: There is a lack of scientific processing parameters specific to the characteristics of mung bean raw materials; The problem of the mung bean skin layer hindering fermentation has not been resolved; No quality evaluation system for mung bean liquor has been established. The effective retention of mung bean active ingredients (flavonoids, GABA, etc.) was not achieved. Summary of the Invention Technical issues

[0007] This invention aims to solve the problems of uneven water absorption, low fermentation efficiency, and unstable flavor caused by the thick skin and special starch structure of mung beans when they are used as a raw material for brewing. It provides a scientific and systematic solid-state fermentation process for producing light-aroma mung bean liquor using Daqu (a type of starter culture). Technical solution

[0008] A solid-state fermentation process for producing a light-aroma mung bean liquor using Daqu (a type of starter culture) includes the following steps: a. Raw material pretreatment: Northeast mung beans are selected, requiring a protein content of ≥22%, a starch content of ≥58%, and freedom from mold and impurities; The process of "low-temperature pre-soaking + water temperature gradient control" is adopted, with the water temperature controlled at 15-25℃ (optimal 18℃) and soaked for 15 hours to make the water absorption rate of mung beans ≥65%.

[0009] b. Optimization of grain steaming process: Steam for 28 minutes (steam pressure 0.12MPa) to loosen the mung beans; Soaking time: Determined according to the variety of mung beans (15 minutes for Northeast mung beans, 10-20 minutes for other varieties); Re-steam for 32 minutes (steam pressure 0.15MPa). Cooked grain requirements: opening rate ≥90%, turning rate ≤5%.

[0010] c. Inoculation and culture process: Dosage of koji: 5-8% (5% for Northeast mung beans, 8% for other mung beans); Inoculation temperature: 31-33℃ in the cold season (room temperature <10℃), 29-31℃ in the hot season (room temperature ≥10℃); Second vaccination: 4 hours apart, with the temperature dropping by 3-5℃.

[0011] d Fermentation process: Storage temperature: 20-22℃ in the cold season, and room temperature (25-28℃) in the hot season. Fermentation cycle: 18-20 days (8-10 days shorter than traditional methods); Acidity control: Acidity during fermentation ≤ 1.8 (calculated as lactic acid).

[0012] e-distillation process: Wine temperature: below 20℃ ≤ 23℃, above 20℃ ≤ 28℃; Flow rate: 2.8-3.2 jin / minute; Heads and tails: 0.5-0.8L of heads and 1.2-1.5L of tails.

[0013] This invention also includes a quality evaluation system: Flavonoid content: ≥10.0mg / L (Vitexin + IsoVitexin); Alcohol-to-acid ratio: 1.2-1.5 (ethanol:total acid); Flavor compound detection: ester content ≥45mg / 100mL.

[0014] This invention also discloses a quality control method for the production process of solid-state fermented Daqu-based light-aroma mung bean liquor, including the following steps: ① Raw material pretreatment, pre-soaking grain water temperature ② Soaking temperature and time ③ Inoculation and culture temperature ④ Temperature of fermentation in the pit ⑤ Steam exploration and distillation ⑥ Temperature and speed of wine flow Further improvements to quality control methods: Raw material pretreatment and pre-soaking water temperature: After the soaking water temperature is evenly adjusted, pour the mung beans into the steamer and stir evenly. The water temperature should be controlled between 0 and 45℃ depending on the variety of mung beans, the thickness of the skin, the air temperature, etc. The soaking water level should be 60 to 80 cm above the grain surface, and the mung bean surface should be leveled. Soaking temperature and time: The soaking time depends mainly on the variety of mung beans and the season. The principle is to soak them until they are slightly firm and have been thoroughly soaked. During the soaking process, continuously lift the mung bean grains from all directions and from top to bottom of the pot, and use your hands to check their softness and observe whether they are thoroughly soaked. Inoculation and culture temperature: When the room temperature is below 10℃ in the cold season, use about 5-10% of the starter culture. Generally, the first inoculation should be done at about 32℃ and the second inoculation should be done at about 28℃. When the room temperature is between 10℃ and 20℃, use about 5-10% of the starter culture. Generally, the first inoculation should be done at about 30℃ and the second inoculation should be done at about 25℃. Temperature and fermentation in the cellar: The temperature of mung beans when entering the cellar should be controlled within the range of 18-25℃ in the cold season and the room temperature should be kept constant in the hot season; adhere to the principle of "low temperature entry into the cellar, quick filling and tight sealing of the container, and low temperature fermentation", tighten the container every day, and do a good job of sealing and managing the cellar during the fermentation period; Before removing the fermentation lees from the cellar, all moldy fermentation lees must be scraped off and discarded. They must not be used for distilling liquor. The fermentation lees must be loosened before removing them from the cellar. After removing the lees from the cellar each day, they must be sterilized with hot water above 70°C, and the inner walls of the cellar and the muddy pools, as well as the sealing film, must be washed. Temperature and speed of wine flow: Temperature control requirements: When the room temperature is below 20℃, it should not exceed 25℃; when the room temperature is above 20℃, it should not exceed 30℃; the wine flow rate should be about 3 jin per minute, and should not exceed 4 jin per minute. During the wine flow, cold water should not be introduced into the ice bucket and the hot water should be replaced.

[0015] Technical effect

[0016] This results in a more uniform water absorption rate of mung beans (≥65%) and an increased alcohol yield: from the traditional 42-45% to 48-52% (an increase of 6-10 percentage points). Stable quality: Flavonoid retention rate ≥85%, flavor compound variety increased by 30%; Production efficiency: Fermentation cycle is shortened to 18-20 days (40% shorter than the traditional 28-35 days); Economic benefits: Each ton of raw material increases production by 300-500 yuan. Detailed Implementation

[0018] This invention discloses a solid-state fermentation process for producing a light-aroma mung bean liquor, characterized by the following steps: Raw material pretreatment: Select mung bean raw materials with protein content ≥22% and starch content ≥58%, and pre-soak them in water at 15-25℃ for 15 hours to ensure that the water absorption rate of mung beans is ≥65%; Steaming process: First steam for 25-30 minutes, soaking time depends on the variety of mung beans (10-20 minutes for Northeast mung beans, 8-15 minutes for other mung beans), second steam for 30-35 minutes, the opening rate of cooked grain ≥90%, and the turning rate ≤5%; Inoculation and culture process: Use 5-8% koji. The temperature for the first koji inoculation is 31-33℃ in the cold season and 29-31℃ in the hot season. The temperature for the second koji inoculation is 3-5℃ lower than the first. Fermentation process in pits: In the cold season, the temperature for entering the pit is 20-22℃; in the hot season, the temperature for entering the pit is 25-28℃ (normal room temperature); the fermentation cycle is 18-20 days; and the acidity during fermentation is ≤1.8. Distillation process: The temperature of the distillate is controlled between 20℃ and 23℃, and between 20℃ and 28℃. The distillation speed is 2.8-3.2 jin / minute.

[0019] This invention also provides a quality control method for the production process of solid-state fermented Daqu-based light-aroma mung bean liquor, including the following aspects: Raw material pretreatment and pre-soaking water temperature: After the soaking water temperature is evenly adjusted, pour the mung beans into the steamer and stir evenly. The water temperature should be controlled between 0 and 45℃ depending on the variety of mung beans, the thickness of the skin, the air temperature, etc. The soaking water level should be 60 to 80 cm above the grain surface, and the mung bean surface should be leveled. Soaking temperature and time: The soaking time depends mainly on the variety of mung beans and the season. The principle is to soak them until they are slightly firm and have been thoroughly soaked. During the soaking process, continuously lift the mung bean grains from all directions and from top to bottom of the pot, and use your hands to check their softness and observe whether they are thoroughly soaked. Inoculation and culture temperature: When the room temperature is below 10℃ in the cold season, use about 5-10% of the starter culture. Generally, the first inoculation should be done at about 32℃ and the second inoculation should be done at about 28℃. When the room temperature is between 10℃ and 20℃, use about 5-10% of the starter culture. Generally, the first inoculation should be done at about 30℃ and the second inoculation should be done at about 25℃. Temperature and fermentation in the cellar: The temperature of mung beans when entering the cellar should be controlled within the range of 18-25℃ in the cold season and the room temperature should be kept constant in the hot season; adhere to the principle of "low temperature entry into the cellar, quick filling and tight sealing of the container, and low temperature fermentation", tighten the container every day, and do a good job of sealing and managing the cellar during the fermentation period; Before removing the fermentation lees from the cellar, all moldy fermentation lees must be scraped off and discarded. They must not be used for distilling liquor. The fermentation lees must be loosened before removing them from the cellar. After removing the lees from the cellar each day, they must be sterilized with hot water above 70°C, and the inner walls of the cellar and the muddy pools, as well as the sealing film, must be washed. Temperature and speed of wine flow: Temperature control requirements: When the room temperature is below 20℃, it should not exceed 25℃; when the room temperature is above 20℃, it should not exceed 30℃; the wine flow rate should be about 3 jin per minute, and should not exceed 4 jin per minute. During the wine flow, cold water should not be introduced into the ice bucket and the hot water should be replaced. Example 1: Northeast mung bean light-aroma baijiu (Example A)

[0020] Ingredients: Northeast mung beans (protein 23.5%, starch 59.2%); Soaking: Soak in 18℃ water for 15 hours, water absorption rate 68%; Steaming the grain: Steam for 28 minutes initially, let it sit in water for 15 minutes, and then steam it again for 32 minutes. Inoculation and culture: Use 6% koji, first koji at 32℃, second koji at 29℃; Fermentation in pit: pit temperature 21℃, fermentation for 19 days; Distillation: Flow temperature 22℃, flow rate 3 jin / minute; Quality: Flavonoid content 12.3 mg / L, alcohol yield 50.2%.

[0021] Example 2: Ordinary mung bean-flavored light-aroma baijiu (Example B)

[0022] Ingredients: Common mung beans (protein 21.8%, starch 57.6%); Soaking: Soak in 20℃ water for 16 hours, water absorption rate 66%; Steaming the grain: Steam for 28 minutes initially, let it sit in water for 12 minutes, and then steam it again for 32 minutes. Inoculation and culture: Use 7% koji, first koji at 30℃, second koji at 27℃; Fermentation in pit: The pit temperature is 23℃, and fermentation takes 20 days; Distillation: Flow temperature 25℃, flow rate 2.8 jin / minute; Quality: Flavonoid content 9.8mg / L, wine yield 49.5%.

[0023] Comparative Example 1: Traditional Process (Control Group)

[0024] Ingredients: Northeast mung beans; Soaking the grains: Soak at room temperature (25℃) for 18 hours; Steaming grains: Steam for 30 minutes initially, let it sit in water for 20 minutes, and then steam again for 35 minutes; Inoculation and culture: Use 10% koji, and set the koji temperature at 35℃; Fermentation in pit: The pit temperature is 25℃, and fermentation takes 28 days; Distillation: Flow temperature 30℃, flow rate 4 jin / minute; Quality: Flavonoid content 6.2mg / L, wine yield 43.5%.

[0025] Experimental Data Comparison Table index Example A Example B Comparative Example 1 Improvement rate Flavonoid content (mg / L) 12.3 9.8 6.2 +97.6% Alcohol yield (%) 50.2 49.5 43.5 +15.4% Fermentation cycle (days) 19 20 28 -32.1% Ester content (mg / 100mL) 52.3 48.7 32.5 +61.2%

Claims

1. A production process for solid-state fermented Daqu-based light-aroma mung bean liquor, characterized in that, Includes the following steps: Raw material pretreatment: Select mung bean raw materials with protein content ≥22% and starch content ≥58%, and pre-soak them in water at 15-25℃ for 15 hours to ensure that the water absorption rate of mung beans is ≥65%; Steaming process: First steam for 25-30 minutes, soaking time depends on the variety of mung beans (10-20 minutes for Northeast mung beans, 8-15 minutes for other mung beans), second steam for 30-35 minutes, the opening rate of cooked grain ≥90%, and the turning rate ≤5%; Inoculation and culture process: Use 5-8% koji. The temperature for the first koji inoculation is 31-33℃ in the cold season and 29-31℃ in the hot season. The temperature for the second koji inoculation is 3-5℃ lower than the first. Fermentation process in pits: In the cold season, the temperature for entering the pit is 20-22℃; in the hot season, the temperature for entering the pit is 25-28℃ (normal room temperature); the fermentation cycle is 18-20 days; and the acidity during fermentation is ≤1.

8. Distillation process: The temperature of the distillate is controlled between 20℃ and 23℃, and between 20℃ and 28℃. The distillation speed is 2.8-3.2 jin / minute.

2. The production process of solid-state fermented Daqu-based light-aroma mung bean liquor according to claim 1, characterized in that, The soaking time depends on the variety of mung bean: 15 minutes for Northeast mung beans and 10-20 minutes for other mung beans.

3. The production process of solid-state fermented Daqu-based light-aroma mung bean liquor according to claim 1, characterized in that, The amount of koji used is determined according to the variety of mung bean: 5-6% for Northeast mung beans and 7-8% for other mung beans.

4. The production process of solid-state fermented Daqu-based light-aroma mung bean liquor according to claim 1, characterized in that, The cooked grains are required to have an opening rate of ≥90% and a turning rate of ≤5%.

5. The production process of solid-state fermented Daqu-style light-aroma mung bean liquor according to claim 1, characterized in that, The acidity during the fermentation process is ≤1.8 (calculated as lactic acid).

6. The production process of solid-state fermented Daqu-style light-aroma mung bean liquor according to claim 1, characterized in that, Flavonoid content ≥10.0mg / L (Vitexin + IsoVitexin), ester content ≥45mg / 100mL.

7. The production process of solid-state fermented Daqu-based light-aroma mung bean liquor according to claim 1, characterized in that, In the distillation process, the first 0.5-0.8L of distillate and the last 1.2-1.5L of distillate are produced.

8. The quality control method for the production process of solid-state fermented Daqu-based light-aroma mung bean liquor according to claim 1 includes the following steps: ① Raw material pretreatment: pre-soaking grain water temperature; ② Soaking temperature and time; ③ Inoculation and culture temperature; ④ Temperature and fermentation in the cellar; ⑤ Probe steam and distill; ⑥ Temperature and speed of wine flow.

9. The quality control method for the production process of solid-state fermented koji-based light-aroma mung bean liquor according to claim 8, characterized in that: Raw material pretreatment and pre-soaking water temperature: After the soaking water temperature is evenly adjusted, pour the mung beans into the steamer and stir evenly. The water temperature should be controlled between 0 and 45℃ depending on the variety of mung beans, the thickness of the skin, the air temperature, etc. The soaking water level should be 60 to 80 cm above the grain surface, and the mung bean surface should be leveled. Soaking temperature and time: The soaking time depends mainly on the variety of mung beans and the season. The principle is to soak them until they are slightly firm and have been thoroughly soaked. During the soaking process, continuously lift the mung bean grains from all directions and from top to bottom of the pot, and use your hands to check their softness and observe whether they are thoroughly soaked. Inoculation and culture temperature: When the room temperature is below 10℃ in the cold season, use about 5-10% of the starter culture. Generally, the first inoculation should be done at about 32℃ and the second inoculation should be done at about 28℃. When the room temperature is between 10℃ and 20℃, use about 5-10% of the starter culture. Generally, the first inoculation should be done at about 30℃ and the second inoculation should be done at about 25℃. Temperature and fermentation in the cellar: The temperature of mung beans when entering the cellar should be controlled within the range of 18-25℃ in the cold season and the room temperature should be kept constant in the hot season; adhere to the principle of "low temperature entry into the cellar, quick filling and tight sealing of the container, and low temperature fermentation", tighten the container every day, and do a good job of sealing and managing the cellar during the fermentation period; Before removing the fermentation lees from the cellar, all moldy fermentation lees must be scraped off and discarded. They must not be used for distilling liquor. The fermentation lees must be loosened before removing them from the cellar. After removing the lees from the cellar each day, they must be sterilized with hot water above 70°C, and the inner walls of the cellar and the muddy pools, as well as the sealing film, must be washed. Temperature and speed of wine flow: Temperature control requirements: When the room temperature is below 20℃, it should not exceed 25℃; when the room temperature is above 20℃, it should not exceed 30℃; the wine flow rate should be about 3 jin per minute, and should not exceed 4 jin per minute. During the wine flow, cold water should not be introduced into the ice bucket and the hot water should be replaced.