Preparation of Antioxidant Peptides Derived from Duck Meat by Enzymatic Hydrolysis

Response surface methodology(RSM) was used to develop an optimal pepsin hydrolysis procedure of duck meat for the production of antioxidant peptides with high DPPH radical scavenging activity. The results showed that the response surface model indicating the effect of substrate concentration, enzyme-to-substrate ratio and hydrolysis time on DPPH radical scavenging activity of duck meat hydrolysates was well fitted(R2=0.995 7, R2Adj=0.992 7). Among three independent variables, enzyme-to-substrate ratio exerted the greatest effect on DPPH radical scavenging activity, while substrate concentration had the least impact. Maximum DPPH radical scavenging activity(83.57 ± 0.20)% was observed for the hydrolysate obtained after 3.54 h of hydrolysis at a substrate concentration of 10.89 g/100 m L and an enzyme to substrate ratio of 0.013%, which was close to the predicted value(84.23%) obtained from RSM at a 95% confidence interval.