How to improve the solubility, dispersion and emulsification of soy protein isolate?

Soy protein is an important nutritional source and industrial raw material for humans. It is cheap and contains no cholesterol. It can not only effectively increase the protein content in food, but more importantly, it exhibits functional properties such as foaming, emulsifying, solubility, Gelability, etc. These properties are used to improve food properties, such as improving taste, increasing elasticity, increasing oil absorption, etc. However, there is still a big gap between its functional properties, such as foaming properties and egg white protein, and emulsifying properties compared with proteins with natural excellent properties such as sodium caseinate. In addition, soy products are prone to odor or contain accumulated toxic substances, resulting in Its application in modern food processing is subject to certain limitations. Therefore, improving the functional properties of soy protein is a major issue in the current food processing industry.

What are the methods for modifying soy protein isolate?

At present, the modification methods of soy protein mainly include physical modification, chemical modification, enzymatic modification and bioengineering modification. Traditional chemical modification methods include alkali method and acid method. Among them, acid method is the most commonly used, but it has many shortcomings such as many reaction by-products, nutritional value will be affected to a certain extent during the reaction process, and there are many safety hazards such as residual chemical modifiers. Especially in European and American countries where food safety is strict, chemical modification affects the scope of its application. Physical modification mainly uses physical interaction forms such as heat, electricity, magnetism, and mechanical energy to change the advanced structure and intermolecular aggregation of proteins, generally not involving the primary structure of proteins; bioengineering refers to genetic engineering modification, enzymatic modification, and physical modification. Modification is better than chemical modification and is the development trend of soy protein modification.

What are the characteristics of enzymatic modification?

By enzymatically hydrolyzing soybean protein with protease, the amino acid residues and polypeptide chains are changed, causing protein molecules or connecting special functional genes, changing the spatial structure and physical and chemical properties, and improving surface hydrophobicity and solubility. Enzymatic modification has several advantages:

1. The enzymatic hydrolysis process is gentle, has little toxic and side effects, and produces few by-products;

2. It can directly provide nutrition to people with indigestion.

3. High efficiency and strong specificity, different enzyme preparations can be selected for production according to the nature of the demand.