Abstract:In order to optimize enzymolysis technology for production of antioxidant peptides from egg white,the effects of enzyme activity,enzymolysis temperature,egg white content and pH were analyzed by orthogonal test with the scavenging rate of hydrolysate to DPPH radical as an index.Scavenging effects of the hydrolysate on hydroxyl radical,superoxide anion radical,lipid peroxidation and its total reduction capacity were investigated using ascorbic acid as controls,and its partial characteristics were also explored.Flavourzyme was screened out from four kinds of alkaline protease,neutral protease,trypsin and flavourzyme and enzymolysis time was 90 min.The optimum conditions were as follows:pH 5,enzymolysis temperature 45 ℃,egg white content 8% and enzyme activity 1 125 U.under such conditions,Scavenging rates of the hydrolysate on DPPH radical was 53.273%.Scavenging effects on hydroxyl(0.308 4～1.542 mg/mL) and superoxide anion radical(0.089～0.443 mg/mL) increased with its concontration,and their half inhibitory concentration(IC50) value was 0.092 mg/mL and 0.021 6 mg/mL for VC,1.24 mg/mL and 0.054 mg/mL for the hydrolysate,respectively.Inhibition effects of the hydrolysate to lipid peroxidation(0.667 ～10.667 mg/mL) decreased with increasing concentration,but it was activated within 0.667～10.667 μg/mL.Isoelectric point of the hydrolysate was about pH=3,scavenging effects of the hydrolysate on hydroxy radical decreased with increasing temperature,and its solubility increased linearly within pH 2～10.
