2.3. Soybean fermentation The soybeans (Northeast soybean, Heilongjiang, PR China) were cleaned and soaked in the water (pH 6.5) overnight at 4 C and then the soaking water was discarded.
2.3. Soybean fermentation The soybeans (Northeast soybean, Heilongjiang, PR China) were cleaned and soaked in the water (pH 6.5) overnight at 4 C and then the soaking water was discarded.