Introduction

Soybean meal is a byproduct from the process of soybean oil extraction, which is mainly composed of protein (40% ~ 44%), fat (1% ~ 2%), carbohydrate (10% ~ 15%), and a variety of minerals, vitamins, and essential amino acids. Its nutrition is relatively comprehensive and balanced. In addition, soybean meal also contains soy isoflavones, phospholipids, and other bioactive substances, which is the most widely used plant-based protein resources. However, there are many kinds of antinutritional factors in soybean meal (trypsin inhibitors, soybean protein antigen, urease, phytic acid, etc.). On one hand, their existence has an inhibition effect on certain digestive enzymes when they are combined with some nutrient component and forms the production that is difficult to digest and absorb. On the other hand, some of them can cause organ damage of animals and leave a bad influence on health and growth. Fermented soybean meal, also known as the microorganism fermented soybean meal the produced under controlled conditions, making use of microbial growth, reproduction and metabolism and the accumulation of useful enzyme and intermediate metabolites of bacteria. Through the microbial fermentation, the fermented soybean meal contains little antinutritional factors and is rich in small molecule soybean peptide, amino acids, enzymes, vitamin and bioactive factors, which has good palatability. It can be applied to piglet feeding, poultry feeding, and aquaculture. It is ideal for alternatives to the fish meal with huge market potential and economic value.