Designing of A Synergistic Mixture of Natural Antioxidants Through Statistical Approaches for Enhancing the Oxidative Stability of Sardine Oil

Abstract

Given the diverse routes of oxidation and a variety of oxidation products, the right combination of antioxidants is expected to exhibit synergistic effects in retarding refined sardine oil oxidation. In this study, a full factorial design (24) was utilized to choose a combination of natural antioxidants which exhibit interactive effect and response surface modelling (RSM) was used to identify the optimal concentration of the selected antioxidant mixture which exhibit synergistic effect. Catechin and resveratrol showed a strong interactive effect among the four natural antioxidants (sinapic acid, vanillic acid, catechin, and resveratrol) studied in sardine oil stored for 50 days at 25ºC under darkness. Two optimal concentrations of interactive antioxidants were found through RSM. Catechin and resveratrol at 0.5 mM and 0.625 mM respectively, exhibited a strong synergistic effect whereas, at 0.5 mM and 3.7 mM respectively, showed prooxidant effect. This is the first of its kind report on the formulation of a synergistic antioxidant mixture for retarding oxidation using statistical approaches.