More than 4,000 years ago, our people began to use mold to saccharify grains to make wine, and the invented distiller's yeast was a great contribution of our working people to the world brewing industry. "If you are distiller's grains, you are just a tiller", so wine-making must rely on the role of distiller's grains. Distiller's yeast is a compound of various microorganisms, which is the driving force of wine fermentation. To make wine, it is necessary to make koji, which is actually a process of expanding the cultivation of brewing microorganisms. Generally, grains are used as raw materials to enrich microorganisms to make koji, and then more grains are saccharified and fermented to make wine. The quality of koji directly affects the quality and yield of wine. Therefore, to make good wine, we must use good songs.

Brewing with grain buds is very different from brewing with distiller's yeast. The former only decomposes the contents of raw materials by using hydrolase produced by grain germination, while the latter uses a variety of microorganisms to attach? Crime cavity? ⒔ Is it appropriate? A hidden hole? ?Stealing tomb? Is the word pepper convex? Kick? Beautiful night? Actor? What's the matter with you? What is an acyl group? Is it hot? What is the value of noisy spectrum and thumb vomiting? Magpie dental caries? Don't hold on? What's wrong with cross-linked amide? /font & gt；

The koji commonly used in liquor production in China can be roughly divided into the following categories: Daqu, Xiaoqu and bran koji. (Commonly used Daqu and Xiaoqu)

First, Daqu

Daqu is made of wheat, barley and peas, which are crushed, mixed with water, pressed into brick-like starter blanks and cultivated at artificially dug temperature and humidity. Daqu contains a variety of microorganisms, such as mold, yeast, bacteria and so on. And it is a multi-bacterial mixed (enzyme) preparation. The species and quantity of microorganisms in Daqu are influenced by the raw materials, koji-making temperature and environment. Because Daqu contains a variety of microorganisms, a wide variety of metabolites and flavor components are formed in the process of wine fermentation. At present, China famous liquor is mostly brewed by traditional Daqu method.

In order to solve the problems in Daqu liquor production, such as large quantity of Daqu, long fermentation period, high food consumption and high labor intensity, people devoted themselves to the study of Daqu microorganisms, explored the growth and decline law of microorganisms in Daqu koji-making process, sought the relationship between Daqu and liquor flavor, trial-produced pure Daqu and strengthened Daqu, and applied mechanized koji-making to reduce labor intensity and improve working conditions.

Second, ditty

Xiaoqu is also called medicinal liquor and Baiyao. Baiyao, wine cake, etc. Rice flour or rice bran is used as raw material, a small amount of Chinese herbal medicine or Polygonum hydropiper is added, yeast is inoculated, and the culture temperature is artificially controlled. Because of the small particles, it is customarily called Xiaoqu. Xiaoqu mainly contains microorganisms such as Rhizopus, Mucor and yeast. Among them, Rhizopus has strong saccharifying ability and certain alcoholase activity, and is often used as saccharifying starter for Xiaoqu liquor and yellow rice wine. For example, Qionglai rice koji and Cantonese wine cake, which produce Xiaoqu wine, are all excellent Xiaoqu varieties for brewing yellow rice wine. Because the production method of Xiaoqu has been passed down from generation to generation, the microorganisms in Xiaoqu have been screened repeatedly, so that Xiaoqu has maintained its excellent quality.

In the process of Xiaoqu production, in the past, in order to promote the growth and reproduction of brewing microorganisms and increase the flavor of wine, some Chinese herbal medicines were often added, but in order to save costs and prevent blind use of Chinese herbal medicines. At present, Chinese herbal medicines have been reduced or even not added to make medicated diet Xiaoqu (medicated diet bran koji), and satisfactory results have been achieved.

The liquor brewed by Xiaoqu has pure taste, elegant aroma and unique style. Because Xiaoqu liquor takes rice as raw material, ethyl lactate, ethyl acetate and β -phenylethanol formed in the process of alcohol production are its main flavor substances, which determines the typical style of Xiaoqu liquor. Guilin Sanhua Liquor, Guangxi Xiangshan Liquor and Guangdong Changle Shao are all top grades of Xiaoqu Liquor, and Dongjiu is also made from Xiaoqu.

At the same time, people often use Xiaoqu to brew nutritious yellow rice wine or prepare rice-soaked yeast for Shaoxing wine, and produce sweet and semi-sweet sealed wine, Xiangxue wine, agarwood wine and so on. Under the action of saccharifying amylase contained in Rhizopus, the glucose content of sweet rice wine can reach more than 20%.

Third, red rice

Monascus is a special starter for brewing yellow rice wine in China. It is made of rice inoculated with koji mother. Monascus mainly contains microorganisms such as monascus and yeast, which has dual functions of saccharification and fermentation. The wine made from red koji is called red koji wine, which has the characteristics of bright color and mellow taste. Monascus can secrete red pigment (C23H24O5) and yellow pigment (C 17H24O4), so it is also commonly used in fermented bean curd, traditional Chinese medicine and food. Monascus also has certain antibacterial and antiseptic abilities. Among them, Wuyi Monascus is a koji made of Monascus, Aspergillus niger, mold and yeast. Yellow-coated monascus is a koji made of monascus, Aspergillus flavus and yeast. They are resistant to temperature and acid, and their saccharification and fermentation ability is stronger than that of Monascus. It is often used to produce yellow rice wine in Zhejiang and Fujian provinces.

Fourth, Maiqu

Maiqu is a kind of koji widely used in China liquor-making industry. It is a multi-strain compound saccharification starter which takes wheat as raw material and is crushed by water. Maiqu mainly contains Aspergillus oryzae, Aspergillus flavus, Rhizopus, Mucor and a small amount of yeast and bacteria. Wheat koji mainly plays the role of saccharification, aroma generation and color enhancement in yellow rice wine brewing, which makes yellow rice wine have special koji flavor and mellow wine taste. According to the different production methods of wheat koji, it can be divided into treading koji, hanging koji, grass-colored koji, explosive wheat koji, pure wheat koji and pure wheat koji. Wheat koji is also used in rice wine production.

mouldy bran

Bran koji is made of bran as the main raw material, inoculated with mold and puffed. Mainly used in the production of bran koji wine, as saccharifying agent. Using bran koji instead of Daqu and Xiaoqu to produce liquor is a new production method after liberation. Its main advantage is that bran koji has strong saccharification ability, the utilization rate of raw starch is as high as 80%, and the grain saving effect is obvious. The fermentation period of bran koji liquor is short, the raw materials are widely used, and it is easy to realize mechanized production. At present, this method has gradually developed from solid production to liquid production, and the role of bran koji has been replaced by liquid koji or enzyme preparation.