Koji is a microorganism that is used to ferment raw grains and starch-containing plants. It is a biological community that is composed of a variety of enzyme preparations and yeasts. It can play its greatest role in anaerobic conditions. . "Quji is the bone of wine", making and selecting koji is an important part of the wine-making process. Many wines are commonly named with song names, such as Daqu wine, Xiaoqu wine, etc. Daqu is named because its finished product is shaped like a big brick. Daqu uses wheat, barley, peas, etc. as the main raw materials. It is rich in microorganisms and various enzymes secreted by microorganisms during the reproduction process, as well as microbial decomposition of koji raw materials. The metabolites formed, such as amino acids, etc. The koji is very small and comes in different shapes and sizes. It is mainly made of rice, wheat, rice bran, etc., with Chinese medicinal materials as auxiliary materials. The strains used in the production of Xiaoqu are naturally selected and cultured. The processing of raw materials and the use of medicinal materials provide good conditions for the reproduction of effective strains. After inoculation, the effective strains multiplied in large quantities. Daqu and Xiaoqu both have the dual functions of saccharification and fermentation when making wine. Wine is a variety of microorganisms organized together to produce esters, acids, alcohols, and various aromas: ① During fermentation activation, be careful to use neutral water or acidic water to make it easier for the microorganisms to wake up and activate. ② The fermentation tank or tank should be sterilized with potassium permanganate or caustic soda or the walls and floors should be washed with quicklime water and dried. ③Choose grains that are clean and have no musty smell, and should be cleaned and soaked in tanks or pools. ④ Allow as few strangers into the fermentation room as possible to observe. During the observation process, one person must clean their hands first and observe from beginning to end. ⑤ If acid production is found in one tank, sterilize and observe it immediately, and do not touch other fermentation tanks or tanks with your hands. During the wine roasting process, it should also be roasted separately to avoid affecting the taste of other wines.