Corn polypeptide powder and method for extracting corn polypeptide by ultrasonic-assisted enzymatic method

The invention relates to a corn polypeptide extraction process, in particular to corn polypeptide powder and a method for extracting corn polypeptide by an ultrasonic-assisted enzymatic method. The method comprises the following steps: (1) a corn fermented mash is in contact with glucoamylase for first enzymolysis, solid-liquid separation is conducted on a first enzymolysis product to obtain a solid-phase enzymolysis product; (2) the solid-phase enzymolysis product is in contact with protease after being mixed with water for second enzymolysis, and second solid-liquid separation is performed on a second enzymolysis product to obtain a hydrolysate rich in polypeptide; and (3) the hydrolysate is heated for enzyme deactivation, cooling is performed, and then, concentrating and drying are performed to obtain the corn polypeptide powder; and the first enzymolysis and/or the second enzymolysis are/is performed under the ultrasonic condition. According to the method, an ultrasonic method andthe glucuronidase are emp