Effect of microbial fermentation on the quality of soybean meal

Summary Soybean meal is an important and inexpensive source of protein in food and animal feed, and contains anti‐nutritional factors such as trypsin inhibitors, antigenic proteins, oligosaccharides, phytic acids and lectins, which limit its application. Microbial fermentation has the capability to improve the nutritional value and biological activities of soybean meal by changing its natural composition. Fermentation results in the degradation of anti‐nutritional factors in soybean meal, an increased amount of small molecular protein peptides and improved content of isoflavone aglycone. However, the nutritional composition and biological activities of the resulting fermented products differ due to the different microbial species and conditions used for fermentation. Compared to soybean meal, fermented soybean meal has several beneficial effects such as digestibility, antioxidant and hypoallergenicity. The objective of this review is to discuss the fermentation processes of soybean meal, as well as outlines some biological activities associated with it. Furthermore, the current application of fermented soybean meal is also summarised.