Effect of enzymatic hydrolysis time, temperature and enzyme to substrate ratio on antioxidant properties of prawn bioactive peptides

Skin, bones, frames, heads and tails are by-products produced during the processing of fish and prawn. These by-products can be enzymatically hydrolyzed and be converted products with beneficial functional properties. So, Protein hydrolysates were prepared from green tiger prawn (Penaeus semisulcatus) waste using flavourzyme and response surface methodology (RSM) based on 18 treatments was applied to study the effect of enzyme to substrate ratio, temperature and time on the protein. The antioxidant activities were measured using 2,2-diphenyl-1-picryl-hydrazyl (DPPH), hydroxyl radical-scavenging activity and ferric reducing antioxidant power. Totally, products have showen better response in 2,2-diphenyl-1-picryl-hydrazyl (DPPH) scavenging activity in comparison to hydroxyl radical-scavenging activity and Ferric (Fe3) reducing antioxidant activity.. Among the treatments produced, 7 treatment (hydrolysis temperature of 54.6 0C together with enzyme to substrate ratio of 1.61 % and hydrolysis time of 105.8 min) with degree of hydrolysis (33.5%) and protein (79.5%) were the optimum conditions to obtain the highest antioxidant properties. These results suggested that prawn waste protein hydrolysates could be useful in the food industry.