Abstract: Whey protein is a high-quality protein in milk, with rich nutritional value and unique physiological functions. Natural whey protein is extremely unstable. In order to make efficient use of whey protein, many modification methods have been developed each with its unique characteristics. This paper reviews the physical, enzymatic and chemical methods as well as new techniques to modify whey protein. The physical methods mainly include heating, high-pressure processing, microwave, ultrasonic, supercritical carbon dioxide fluid and low-temperature plasma. The enzymatic methods mainly include enzymatic hydrolysis and enzymatic cross-linking. The chemical methods include phosphorylation, glycosylation, acylation, deamidation and acidification. This article summarizes the mechanisms of the various modification methods and their impact on the properties of whey protein, and discusses future trends in the application and development of whey protein modification techniques.

Key words: whey protein; physical modification; chemical modification; biological modification