Optimization of enzymatic hydrolysis of green tiger shrimp (Penaeus semisulcatus) head wastes protein with Response Surface methodology

In order to optimization of protein hydrolysis condition (including enzyme to substrate ratio (E/S), temperature and time) for achieving the highest antioxidant activity, the green tiger prawn (P. semisulcatus) mince was tested via commercial protease (Alcalase® 2.4L) based on the response surface designed method in 18 treatments and then dried to obtain powder in freeze dryer. The antioxidant activity experiments were tested in three ways including DPPH radical scavenging activity, hydroxyl radical scavenging activity and reducing power. Overall, in comparison with hydroxyl radical scavenging activity and reducing power, the products had better response to DPPH radical scavenging activity. Alcalase inhibited degree of hydrolysis 49.7% and protein content 86.9 % (on dry basis). Among the treatments, which were produced by Alcalase, treatment number 11 (E/S 2.5%, Temperature 75°C and Time 85 min) was selected as the optimum condition on the basis of antioxidant activity.