Bioactive properties of marine fish skin gelatin hydrolysate: Optimisation using response surface methodology

Abstract

Adverse effects of free radicals on food oxidation have increasingly been investigated recently. Antioxidants have many health benefits as bioactive materials and are widely used in food industries. The effects of three main factors namely, time (60, 150, 240 min), temperature (40, 52, 65℃) and enzyme to substrate ratio (1, 3, 5%) on fish gelatin hydrolysation were studied in order to obtain optimum antioxidative properties. Response surface methodology (RSM) was used to fit the
model and ridge analysis to optimise the selected factors. The percentage of Fe2+ chelating activity was considered as the response. R2 confirmed that the model fitted well with the experimental data (R2 = 0.97). Optimal conditions were found to be at a temperature of 56.55°C, enzyme to substrate ratio of 4.93% and time of 149.23 min. Under optimum conditions, metal chelating activity achieved was 82.33%. The results showed that fish skin gelatin hydrolysate had good antioxidative
properties and could be a candidate for in vivo studies for industrial applications.

Keywords: Antioxidant, Fish gelatin hydrolysate, Metal chelating activity, Response surface methodology