Fermented rice wine, also known as mash, is a kind of rice wine with sweet taste. It has not been filtered and purified, and its degree is very low. Southerners use fermented rice wine to mix eggs and milk, which is a postpartum tonic and tastes good. Rice wine generally refers to the wine brewed from rice. The slightly better rice wine is generally filtered and purified, and the sweetness is not heavy, and the wine taste is heavy. More suitable for people who love to drink. Wash the screened glutinous rice with water, put it in a pot and steam it over strong fire for about 1 hour, and take it out after it is cooked. Then pour the steamed rice into a pot of warm water, rub it (so as to avoid sticky rice from sticking to each other), and then pick it up and drain it. When the temperature drops to about 4℃, grind a certain amount of sweet wine koji (generally 1 kg of rice wine per bag), pour 8% of koji into rice and mix well. Put it in a pot or jar, and then sprinkle the remaining 2% yeast evenly on it. Take warm water at 35℃, slowly pour it into the basin, cover it and seal it, and keep the temperature at 3℃ for about two days.