Abstract: This paper reports the use of response surface methodology based on Box-Behnken experimental design to optimize the enzymatic hydrolysis of buffalo milk casein by trypsin for preparing antibacterial peptides. The optimum hydrolysis conditions were determined to be hydrolysis at 43 ℃ for 3.4 h with an enzyme/substrate ratio of 2.5%. Under these conditions, the degree of hydrolysis (DH) of buffalo milk casein was 4.76%, and the obtained hydrolysate showed an inhibitory rate as high as 81.34% against Escherichia coli.

Key words: casein, antibacterial peptide, optimization, response surface methodology