Abstract

The potential of both natural and synthetic antioxidants, alone and in combination, to prevent the degradation of highly unsaturated fat isolated from the Pacific sardine, Sardinops melanostictus, during storage has been examined in this study. Accelerated aging methods on fish oil samples, enhanced with individual and combinations of antioxidants, were used. The fish oil was evaluated for quality by analyzing its physicochemical properties, fatty acid composition, and amounts of fat-soluble vitamins. The results showed a notable rise in peroxide value, acid value, and para-anisidine value in fat samples lacking antioxidants. This was accompanied by a decrease of 3.4–5 times in omega-3 polyunsaturated fatty acids (PUFAs) and 40–80% in fat-soluble vitamins. These findings suggest the presence of ongoing lipid oxidation processes and degradation. The use of specific antioxidants, such as α-tocopherol acetate at a concentration of 2%, betulin at a concentration of 0.3%, and ethoxyvine at a concentration of 0.14%, resulted in a slight decrease in the rate of fat autoxidation and the protection of PUFAs and vitamins. A synergistic effect was observed when α-tocopherol acetate and ethoxyvine, or betulin and ethoxyvine, were combined at half the single levels. This combination improved fish oil oxidation resistance. These antioxidant blends inhibited oxidative processes in unsaturated fish oil using salicylic acid amide. This slowed omega-3 PUFA and fat-soluble vitamin breakdown.

Key words: Sardinops melanostictus, fats, PUFAs, oxidation, antioxidants