Hello! Em raw dew is composed of lactic acid bacteria, photosynthetic bacteria and other beneficial microorganisms, which are widely used in agriculture and industry. Your question of using it and soybean powder for secondary fermentation is not accurate enough. The combination of the two is to improve the nutritional value of soybean flour by accelerating the fermentation of soybean flour through em raw dew. There is no secondary fermentation, and you haven't made it clear where it will be used after fermentation. I will introduce the method of making organic fertilizer from soybean powder fermented by em raw dew. Its proportion: original dew: 1: 1, brown sugar: 500- 1000, bean flour: 30-35%, water: 1000 kg of bean flour, 1 or 2 kg of brown sugar, 300. Dissolve brown sugar first, then pour in the original em dew, add water, and then mix it with bean powder. Humidity should be held in a ball by hand, and it is advisable to disperse when it meets water. Put the stirred mixture into a container, compact and seal it, and put it in a place without rats at room temperature for anaerobic fermentation for 4 days in summer and about 10 days in winter until it emits a slightly sweet and sour koji flavor, indicating that the fermentation is complete. The fermentation device should not be exposed to air, and the water content is appropriate. When it is cold, it can be unsealed first, and then sealed when the temperature reaches 40 degrees, which can speed up the fermentation.