Method for preparing sorghum black-coat red yeast rice by cultivating black yeast seeds and red yeast seeds by using sorghum rice

Abstract

The invention relates to the technical field of food biology, in particular to a method for preparing sorghum black-coat red yeast rice by cultivating black yeast seeds and red yeast seeds with sorghum rice. Comprising the following steps: S1, material preparation: performing liquid state fermentation on a monascus strain for six days to obtain a mother grain, selecting peeled sorghum rice, soaking, steaming, cooling for later use, and grinding a black yeast seed into powder; s2, inoculating: adding the cooled sorghum rice in the S1 into the red distiller's grains, uniformly stirring, then adding the aspergillus niger strain, and uniformly stirring; s3, cave dwelling pile fermentation: piling the inoculated sorghum rice in a cave dwelling synthesized by clay and red soil sand, controlling the temperature to 34-38 DEG C, fermenting for 1-2 days, and spreading for fermentation until the rice skin is slightly red; s4, supplementing water for the third time; and S5, drying. The invention provides the method for preparing the sorghum black-coat red yeast rice by cultivating the black yeast seed and the red yeast seed by using the sorghum rice, wherein the sorghum black-coat red yeast rice is strong in saccharifying power, the brewed wine has special sorghum rice fragrance, and the trace elements are richer.

Description

Technical Field

[0001] The present invention relates to the field of food biotechnology, and specifically to a method for cultivating black koji and red koji with sorghum rice to produce sorghum Wuyi red koji. Background Art

[0002] Traditional red koji preparation technology uses indica rice as the substrate and solid-state fermentation is carried out using Monascus spp. The saccharifying enzyme activity and metabolite diversity are limited by the action of a single strain. As a composite koji strain with the dual functions of Monascus and Aspergillus niger, although Wuyi red koji shows unique advantages in yellow rice wine brewing, there are three technical bottlenecks in the existing technology:

[0003] First, the conventional process mostly uses rice as the substrate, resulting in the lack of specific flavor substances of grains in the fermentation products; second, the co-growth control of Aspergillus niger and Monascus is insufficient, and the phenomenon of strain competition inhibition often occurs; third, the traditional open-air fermentation has defects such as large fluctuations in temperature and humidity and high risk of contamination by miscellaneous bacteria, affecting the stability of the koji strain and the activity of the enzyme system.

[0004] At present, a three-step temperature control method is used to improve the preparation of red koji, but the problems of strain cooperation and substrate adaptability have not been solved; at the same time, although the mixed koji-making technology attempts to apply composite strains, there are still defects in the metabolite imbalance in terms of strain ratio and fermentation time sequence control. In addition, traditional Wuyi red koji preparation mostly uses a naturally enriched Aspergillus niger community, and the professional breeding of Aspergillus niger strains has not been realized, resulting in a fluctuation of more than 30% in saccharifying enzyme activity.

[0005] In view of the above technical pain points, a method for cultivating black koji and red koji with sorghum rice to produce sorghum Wuyi red koji is needed. Summary of the Invention

[0006] The technical problems to be solved by the present invention are the insufficient flavor of the fermentation products caused by the traditional substrate singularity, the problem of strain competition inhibition between Monascus and Aspergillus niger, and the stability defect caused by the open fermentation environment.

[0007] The technical solution adopted by the present invention is: a method for cultivating black koji and red koji with sorghum rice to produce sorghum Wuyi red koji, including the following steps:

[0008] S1. Preparation of materials: Using the liquid fermentation of red koji strain for six days as the fermented mother, selecting peeled sorghum rice, soaking, steaming and then cooling for standby, and grinding the black koji strain into powder;

[0009] S2. Inoculation: Adding the cooled sorghum rice in S1 to the red fermented mother (liquid strain), stirring evenly, and then adding the black koji strain and stirring evenly;

[0010] S3, Fermentation in the cave: Place the inoculated sorghum grains in a cave made of a combination of clay and red soil sand. Control the temperature at 34 - 38 °C and ferment for 1 - 2 days. First, spread them out with a thickness of 20 cm, and then spread them evenly to cover the cave floor until the surface of the grains turns slightly red.

[0011] S4, Three - time water addition:

[0012] a. First water addition: Put the slightly red grains into a sack, soak them in water, then spread them out and continue to ferment until the grain skin turns 7 - 8 parts red.

[0013] b. Second water addition: Put the 7 - 8 parts red grains into a sack again, soak them in water, then spread them out. Control the temperature at 35 - 40 °C and ferment until the grain core turns slightly red, the grain skin turns 9 parts red and the surface turns gray - white.

[0014] c. Third water addition: Put the 9 parts red grains into a sack, soak them in water until they absorb enough water, then lift them out and put them back into the cave to spread on the floor. Ferment until the grain core turns red and the surface turns completely red. Then continue to spread on the floor and let it stand and ferment for 2 days, and sprinkle water periodically. A large amount of black - clothed mold grows and turns gray - black.

[0015] S5, Drying: Put the fermented black - clothed red yeast rice into bags and take it out of the cave. Spread it evenly on a round winnowing basket, put it on a shelf and turn it over and sun it until it is completely dry to obtain the finished product.

[0016] As a further scheme of the present invention: The sorghum grains in S1 are June grains, and they must go through another whitening process to remove rice bran, broken rice, husk and impurities until the purity reaches 98% - 100%. The soaking time of the sorghum grains is 6 - 12 hours, and the water level is 30 cm higher than the sorghum grains. After soaking, the sorghum grains are fished out, rinsed clean with clear water, drained of water and then put into a steamer and steamed until the grain core is thoroughly cooked.

[0017] As a further scheme of the present invention: The black - clothed koji species in S1 is the koji species prepared by the ancestral formula of the Wang family in Qiantang.

[0018] As a further scheme of the present invention: The cave wall in S3 is made of adobe bricks, and the ground is made of a mixture of clay and red soil sand. The environment is dry and cool, and the humidity and acidity environment are suitable for the reproduction of Monascus purpureus and Aspergillus niger.

[0019] As a further scheme of the present invention: The end point of fermentation in S4 is that the black - clothed mold shortens, the grain core turns dark red through and the surface turns completely red.

[0020] As a further scheme of the present invention: The whole process of this method takes 13 days.

[0021] The beneficial effects of the present invention:

[0022] 1. Strong saccharifying power: During the fermentation process of Wuyi red koji made from sorghum, Aspergillus niger and Monascus purpureus work synergistically, significantly enhancing the activity of glucoamylase. The combination of the high saccharifying ability of Aspergillus niger and the metabolite diversity of Monascus purpureus makes the saccharifying power of Wuyi red koji made from sorghum stronger than that of traditional red koji, enabling more efficient conversion of starch into fermentable sugars and providing higher fermentation efficiency for subsequent brewing processes.

[0023] 2. Unique sorghum aroma: Compared with traditional red koji made from indica rice as the substrate, using sorghum as the substrate endows Wuyi red koji with a unique sorghum aroma. This grain-specific flavor substance is retained and enhanced during the fermentation process, making the brewed liquor body have a unique sorghum aroma, enriching the flavor hierarchy of the liquor and enhancing the market competitiveness of the product.

[0024] 3. Richer trace elements: Sorghum itself is rich in various trace elements such as iron, zinc, and magnesium, and these elements are further released and enriched during the fermentation process. Through the double fermentation of Aspergillus niger and Monascus purpureus, Wuyi red koji made from sorghum not only retains the nutritional components in sorghum but also produces more beneficial trace elements through microbial metabolism, making the finally brewed liquor body more nutritious and having higher health value.

[0025] 4. Synergistic control of strains: By precisely controlling the fermentation temperature, humidity, and water replenishment timing in the present invention, the problem of competitive inhibition between Aspergillus niger and Monascus purpureus is effectively solved, and the synergistic growth of the two strains is achieved. This synergistic effect not only improves the fermentation efficiency but also ensures the balance of metabolites, making the enzyme system activity of Wuyi red koji more stable and controlling the fluctuation of glucoamylase activity at a lower level.

[0026] 5. Stable fermentation environment: Using the cave heap fermentation technology, the temperature and humidity environment in the cave is relatively stable, avoiding the problems of large temperature and humidity fluctuations and high risk of miscellaneous bacteria contamination in traditional open-air fermentation. This stable fermentation environment ensures the quality consistency of Wuyi red koji and improves the stability and reliability of the product. Detailed implementation mode

[0027] The present invention will be further described below.

[0028] Example: Preparation of Wuyi red koji made from sorghum of the present invention

[0029] A method for preparing Wuyi red koji made from sorghum by cultivating Aspergillus niger and Monascus purpureus with sorghum takes 13 days in total and includes the following steps:

[0030] S1. Preparation of materials: Use the liquid fermentation of Monascus strains for six days as the fermented starter. Select peeled sorghum rice, soak it, steam it, and then cool it for standby. The sorghum rice is June rice and must go through another whitening process to remove rice bran, broken rice, husk, and impurities until the purity reaches 98%-100%. The soaking time of sorghum rice is 6-12 hours, and the water level is 30 cm higher than the sorghum rice to enable it to absorb water better. After soaking, the sorghum rice is fished out, rinsed clean with water, drained, and then put into a steamer and steamed until the rice core is thoroughly cooked. Grind the Aspergillus niger strain (the Aspergillus niger strain is the strain prepared according to the ancestral recipe of the Wang family in Qiantang) into powder.

[0031] S2. Inoculation: Add the cooled sorghum rice in S1 to the red fermented starter (liquid strain), stir evenly, and then add the Aspergillus niger strain and stir evenly.

[0032] S3. Fermentation in the cave cellar: The black Monascus mainly relies on the reproduction and growth of Monascus purpureus and Aspergillus niger, and the suitable temperature for it is about 34 degrees Celsius. Stack the inoculated sorghum rice in a cave cellar made of a mixture of clay and red soil sand. The wall of the cave cellar is built with adobe bricks, and the ground is made of a mixture of clay and red soil sand. The environment is dry and cool, and the humidity and acidity environment are suitable for the reproduction of Monascus and Aspergillus niger. Control the temperature at 34-38°C and ferment for 1-2 days. First, spread it out with a thickness of 20 cm, and then spread it evenly to cover the cave cellar bed until the surface of the rice turns slightly red, indicating that the Monascus starts to reproduce.

[0033] S4. Three times of water replenishment:

[0034] a. The first water replenishment: Put the slightly red rice grains into a hemp bag, soak them in water, and then spread them out, and continue to ferment until the rice skin turns 7-8 parts red.

[0035] b. The second water replenishment: Put the 7-8 parts red rice grains into a hemp bag again, soak them in water, and then spread them out. The black Aspergillus niger also starts to reproduce rapidly during the fermentation on the bed. At this time, the fermentation power is strong. Control the temperature at 35-40°C, and Monascus and Aspergillus niger reproduce in large numbers again and penetrate the rice core, fermenting until the rice core turns slightly red, the rice skin turns nine parts red and the surface is grayish white, resembling red rice wearing white clothes.

[0036] c. The third water replenishment: Put the nine parts red rice grains into a hemp bag and soak them in water to make them absorb enough water, then lift them up, and then go back to the cave cellar to spread them on the bed. Spread and ferment until the rice core is red and the surface is completely red. A large amount of black hair of the black Monascus reproduces at night, and the black hair grows long. Continue to spread and let it stand and ferment for 2 days, and sprinkle water periodically. A large amount of black hair of the black Monascus reproduces and turns grayish black. The end point of fermentation is that the black hair of the black Monascus shortens, the rice core is dark red and the surface is completely red.

[0037] S5. Drying: Put the fermented black Monascus into bags and take it out of the cave cellar, spread it evenly on a round winnowing basket, put it on the shelf and turn it over and dry it until it is completely dry to obtain the finished product.

[0038] Comparative experiment: Preparation of traditional sorghum black Monascus

[0039] The preparation method of traditional sorghum black koji is similar to that of the present invention, but there are the following differences:

[0040] Substrate: The traditional method uses ordinary sorghum rice without the whitening process, resulting in lower purity.

[0041] Strain: The traditional method uses a naturally enriched Aspergillus niger community without professional breeding.

[0042] Fermentation environment: The traditional method uses open-air fermentation, with large fluctuations in temperature and humidity and a high risk of contamination by miscellaneous bacteria.

[0043] Water replenishment control: The timing and amount of water replenishment in the traditional method are not precisely controlled, resulting in uneven fermentation.

[0044] Comparison results:

[0045] The following table compares the differences between the sorghum black koji of the present invention and traditional sorghum black koji in terms of saccharifying power, flavor characteristics, and trace element content:

[0046] Comparison items The sorghum black koji of the present invention Traditional sorghum black koji Saccharifying power The activity of glucoamylase is significantly improved, and the fluctuation is less than 10% The activity of glucoamylase is relatively low, and the fluctuation reaches more than 30% Flavor characteristics It has a unique sorghum aroma and rich flavor levels The flavor is single and lacks the specific aroma of grains Trace element content The content of trace elements such as iron, zinc, and magnesium has increased significantly The content of trace elements is relatively low and the nutrition is unbalanced Fermentation stability The fermentation environment is stable and the risk of contamination by miscellaneous bacteria is low The fermentation environment is unstable and the risk of contamination by miscellaneous bacteria is high Strain synergy Aspergillus niger and Monascus purpureus grow synergistically, and the metabolites are balanced Strain competition inhibition, and the metabolites are unbalanced

[0047] Conclusion:

[0048] It can be seen from the comparison that the sorghum black koji of the present invention is significantly superior to traditional sorghum black koji in terms of saccharifying power, flavor characteristics, trace element content, and fermentation stability. By optimizing the substrate selection, strain co-control, and fermentation environment management, the present invention has successfully solved the technical bottlenecks in the traditional preparation method and prepared high-quality sorghum black koji, which has broad application prospects and market potential.

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for producing kaoliang black koji and red koji by using kaoliang rice to produce kaoliang black koji, characterized in that: The following steps are involved: S1. Preparation of materials: using red yeast rice to ferment in liquid form for six days as a mother liquor, soaking and steaming peeled sorghum rice, cooling and setting aside, and grinding black yeast rice into powder; S2, inoculation: add the cooled sorghum rice in S1 to the red yeast rice and mix well, then add the black koji fungus and mix well; S3, cave fermentation: Place the inoculated sorghum rice in a cave made of clay and red soil sand, control the temperature at 34-38°C for fermentation for 1-2 days, first spread it out to a thickness of 20CM, then spread it out evenly to cover the cave bed until the rice surface is slightly red; S4, three times of water replenishment: a. First water replenishment: Put the slightly red rice grains into a sack, soak them in water, spread them out, and continue to ferment until the rice skin turns 70% to 80% red; b. Second water replenishment: put 70%-80% red rice grains into sacks again, soak them in water and spread them out, control the temperature at 35-40°C, and ferment until the rice core is slightly red, the rice skin is 90% red and the surface is grayish white; c. The third water replenishment: put the nine-point red rice grains into a sack and soak it in water. After it absorbs enough water, lift it up and put it back into the cave to make a bed. Spread and ferment until the rice core and the surface are completely red. Continue to spread the bed and let it stand for 2 days to ferment, and sprinkle water periodically. The black hair will multiply in large quantities and turn gray-black; S5. Drying: The fermented black-clothed red yeast rice is packed in bags and taken out of the cave. It is evenly spread on a round winnowing basket and placed on a shelf for drying until it is completely dry to obtain the finished product.

2. The method for producing kaoliang black koji and red koji by using kaoliang rice as claimed in claim 1, characterized in that: The sorghum rice in S1 is June rice, which needs to be milled once more to remove rice bran, broken rice, husk and impurities until the purity reaches 98%-100%. The sorghum rice is soaked for 6-12 hours, and the water is 30 cm higher than the sorghum rice. The soaked sorghum rice is taken out and rinsed with clean water, and then put into a steamer after draining the water, and steamed until the rice core is transparent.

3. The method for producing kaoliang black koji and red koji by using kaoliang rice as claimed in claim 1, characterized in that: The Wuyi Qu species in S1 is a Qu species prepared using the ancestral recipe of the Qiantang Wang family.

4. The method for producing kaoliang black koji and red koji by using kaoliang rice as claimed in claim 1, characterized in that: The cave wall of the cave in S3 is made of earth bricks, the ground is made of a mixture of clay and red soil sand, the environment is dry and cool, and the humidity and acidity are suitable for the reproduction of red koji and black koji.

5. The method for producing kaoliang black koji and red koji by using kaoliang rice as claimed in claim 1, characterized in that: The fermentation end point in S4 is that the rice hair is shortened, the rice core is dark red and the rice skin is completely red.

6. The method for producing kaoliang black koji and red koji by using kaoliang rice as claimed in claim 1, characterized in that: The method took 13 days in total.