Fermented soymilk is receiving more concern worldwide as consumers have pursued a healthy and low-carbon lifestyle in recent decades. Fermented soymilk has not only an inexpensive cost and plentiful nutrition including high content of proteins, low in cholesterol, and lactose-free but also can produce many bioactive substances after fermentation by various microorganisms. The bioavailability of nutrients such as the digestion of proteins and the reduction of antinutritional factors are improved because of the hydrolyzation of different enzymes generated from the growth of microorganisms in soymilk. Furthermore, the contents of bioactive compounds including the bioactive peptides and the free isoflavones are promoted significantly. These bioactive compounds are associated with some health benefits such as antihypertensive, antioxidant, antidiabetic, anticancer, and hypocholesterolemic effects. The sensory qualities are changed as well after fermentation. This shows that fermented soymilk can be expected as a novel nutritional and functional food in the food markets. This review covers the changes in main nutrients, bioactive compositions, and flavor compounds after the fermentation of soymilk to provide more information for the development of fermented soy milk as one of the burgeoning soy products.
