Abstract:Taking pig blood as raw material and scavenging rate of DPPH free radical as index， antioxidants peptide was prepared with enzymatic hydrolysis method， and the optimal enzymatic hydrolysis conditions were achieved by response surface methodology. Results showed that broken rate of red blood cells could reach 97.1 % by treatment of ultrasonication in ice bath， alkaline protease was selected as the better enzyme for preparation of antioxidant peptides from hydrolyzed pig haemoglobin. Under the optimal enzymatic hydrolysis conditions of temperature 58 ℃ ， pH 7.7， enzyme concentration 6.5 % ， the actual scavenging rate of DPPH free radical reached 96.94 %， which was consistent with the predicted results.