2. 2 ~ 3 minutes after opening, pour out the upper rice soup, and keep the rice and water below to continue cooking porridge or rice.
3. After the black rice soup is cooled, pour it into the prepared pickle jar and add a small amount of old sour soup as the base material.
4. Cover the jar and seal it with water. It takes 2-3 days to ferment in hot weather and longer in cold weather.
5. Fermented white sour soup can be taken at any time. If you think there is less white sour soup, add new rice soup. After addition, it can be taken again after fermentation for 24 hours.