The effects of hydrolysis condition on the antioxidant activity of protein hydrolysate from Schizothorax zarudnyi's waste

Oxidation plays an important role in diseases and reduction of fats and oil quality in food products during processing and storage. Fish processing industry produce a lot of waste including skin, head, viscera, liver, and etc. These wastes contain good amount of rich protein material that are normally processed into low market-value products, such as animal feed, fish meal and fertilizer. Present work was conducted to study the effect of protein hydrolysis condition on antioxidant activity of hydrolysate obtained from Schizothorax zarudnyi wastes. Pepsin was used for protein hydrolysis and DPPH radical scavenging power was used to evaluate antioxidant activity of hydrolysates Hydrolysis condition variables were as enzyme concentration (1, 2, 3, 4, 5 and 10 %), substrate concentration (3, 4, 5, 6 and 7 g), reaction temperature (35, 37, 39 and 42 ºC), and hydrolysis time (6, 24, 30, 48, 72 and 96 hours). The optimum conditions obtained were as follows: enzyme concentration of 5%, substrate amount of 5 g, temperature of 37 ºC and time of 72 hours, under which, DPPH radical scavenging activity of 50.06 % was obtained.