Enzymatic hydrolysis of soybean meal and hydrolysates analysis

Soybean meal were hydrolyzed with papain,trypsin and As1.398 subtilisin.The optimum conditions of enzymatic hydrolysis were studied with the degree of hydrolysis of soybean meal through orthogonal test.The results showed that the optimum hydrolysis conditions of papain were pH 7.5,temperature 50,time 5 h,enzyme concentration 5% of soybean meal protein.The optimum hydrolysis conditions of trypsin were pH 7.0,temperature 50,time 7 h,enzyme concentration 5% of soybean meal protein.The optimum hydrolysis conditions of As1.398 subtilisin were pH 6.5,temperature 50,time 7 h,enzyme concentration 5% of soybean meal protein.Through SDS-PAGE gel electrophoresis analysis of hydrolysates of soybean meal,it showed that the composition and amount of protein and peptides in the hydrolysates were different with hydrolysis conditions and enzymes.The higher the degree of hydrolysis was,the more the small molecular peptides were.