Selective Extraction of Surface-active and Antioxidant Hydrolysates from Yellowfin Tuna Red Meat Protein using Papain by Response Surface Methodology

Abstract

The present study was focused on the selective extraction of surface-active and antioxidant hydrolysates from yellowfin tuna (Thunnus albacares) red meat based on separate hydrolytic conditions using papain. The effect of key processing variables viz., enzyme-substrate ratio (0.25-1.5 %) and hydrolysis time (30-240 min) under optimized temperature and pH, on the protein recovery, surface-active and antioxidative properties, was determined using Response Surface Methodology (RSM) with a central composite design. Single and combined effects of the variables on the responses were studied by formulating 13 experimental runs. The coefficient of determination (R^2) ranged between 0.73 – 0.99 indicating the suitability of the fitted regression models. The optimum hydrolytic conditions to get hydrolysates having superior surface-active properties were enzyme-substrate ratio (E/S) of 0.41 % and 30 minutes hydrolysis time with a desirability of 0.611. Similarly, the optimum conditions to exhibit the highest antioxidative properties with a desirability of 0.932 were 1.28 % E/S and 240 minutes hydrolysis time.