The making process of vinegar! Especially the time of each link!

The rice vinegar brewed by this method is brown-black, clear and sour. Every 50 kilograms of glutinous rice can brew 225 kilograms of rice vinegar, and the vinegar residue can be pickled with sauerkraut or mixed with feed to feed pigs, which has good economic benefits.

1. Raw material formula: 50 kg of glutinous rice and 2 kg of distiller's yeast (sweet distiller's yeast or white spirit yeast, which is ground into powder when used).

Second, the operation technology

1. Soak: Soak the glutinous rice with clear water, and the water level is 20 cm higher than the rice layer. When the temperature is lower than 15℃ in winter and spring, soak 12- 16 hours; Soak for 8- 10 hour when the temperature is above 25℃ in summer and autumn. Water must be changed 1-2 times in summer to prevent rice from turning sour.

2. Steamed rice: Rinse the soaked glutinous rice with water, drain the water slightly, and then steam the rice. Steam after the steam is full 10 minute; Sprinkle appropriate amount of water on the rice layer and steam for 10 minute. Until the rice grains are swollen and shiny, loose and soft, and chewing is not sticky.

3. Stirring: After the rice is cooked, wash it with clear water to cool down, drain the water and spread it on a bamboo mat. When the product temperature drops to 25-30℃, the koji powder is quickly and evenly mixed.

4. Fermentation: put the rice mixed with distiller's yeast into the jar, wrap sacks or straw mats around the jar to keep warm in winter and spring, ventilate and dissipate heat indoors in summer and autumn, and keep the room temperature at 25-30℃. After 24 hours, you can smell a slight bouquet; After 36 hours, the liquor oozed, golden in color, sweet and slightly sour in taste, and fragrant in wine, indicating that the fermentation was normal.

5. Vinegar: In the fermentation process, in order to make saccharification complete, it is necessary to continue fermentation for 3-4 days to promote the production of more alcohol. When the liquor starts to sour, 200-225 kilograms of water should be added to every 50 kilograms of steamed rice to reduce the alcohol concentration of liquor, which is beneficial to the reproduction and growth of acetic acid bacteria in air and natural vinegar.

6. Finished product: After the vinegar is put into the tank, it takes 20-30 days in summer and autumn and 40-50 days in winter and spring, and the vinegar turns sour and mature. At this time, there is a layer of acetic acid bacteria film on the surface of vinegar, which has a pungent sour taste. The upper layer of vinegar is clear and orange, while the middle and lower layers are milky white and slightly turbid. Mix them evenly, add spiced seasoning and sugar color into white vinegar, precipitate and filter to get fragrant vinegar. Mature vinegar should be stored for 1-2 years.