China is the world's largest cotton-producing country and has abundant cottonseed protein resources. Cottonseed protein is a product with a crude protein content of more than 50% produced from cottonseed or cottonseed meal . It is a high-quality protein feed.

However, because it contains the harmful substance free gossypol, if it is fed directly to animals, it can affect the production performance of the animals. Some studies have shown that the use of microbial fermentation technology can effectively reduce the gossypol content; and after cottonseed protein is fermented by microorganisms, the organic content contained in it The contents of acids, digestive enzymes, and small peptides were significantly increased, and the nutritional value was also improved.

Cottonseed protein can be divided into two parts : non-storage protein ( NSP ) and storage protein ( SP ) according to its function in cottonseed . Storage protein accounts for about 70% and non-storage protein accounts for about 30% .

These two parts of protein are very different in molecular weight, solubility, functional properties and nutritional value. According to the difference in protein solubility, cottonseed protein mainly includes two types of proteins, globulin and gluten. The main component is globulin, which accounts for about About 90% , followed by gluten.

The quality of cottonseed protein is similar to that of legume protein, and its nutritional value is much higher than that of cereal protein. From the perspective of amino acid composition, except for methionine, which is slightly lower, the other essential amino acids all meet the requirements recommended by the Food and Agriculture Organization of the United Nations and the World Health Organization ( FAO / WHO ). standards. Therefore, cottonseed protein is a good protein food or feed protein source .

There are four main extraction methods for cottonseed protein: alkali acid precipitation, salt extraction, enzymatic extraction, and reverse micelle method.