It seems to be a different concept... You have a misunderstanding about soybean juice

Soybean juice is actually the scraps from making mung bean starch or vermicelli. It is soaked in mung beans to twist the skin after fishing, add water to grind into a fine pulp, poured into the vat fermentation, sunk into the bottom of the vat for the starch, the upper layer of floating that is for the bean juice. The fermented bean juice shall be boiled in a large casserole with water first, into the fermented bean juice and then boiled, and then keep warm with a small fire, and eat with the sheng.

Fermentation is not the same as rancidity! Rancid is spoiled and can no longer be drunk. Soymilk is made by grinding beans and boiling them with water, it's totally different ah ........

The flavor of soy juice may not be acceptable to most people, but that one is definitely not bad!