Inhibitory effect of an antioxidant complex on the lipid oxidation of freeze-dried convenience food

This study was conducted to develop an antioxidant complex that inhibits lipid oxidation of freeze-dried convenience food rich in animal resources. The antioxidant capacities of various botanical extracts were evaluated, and those of both 50% and 80% ethanolic extracts of green tea (GT50 and GT80) were found to be the higher than those of other botanical extracts, although the capacity of L-ascorbic acid used as comparative antioxidant was the highest (p<0.05). A freeze-dried chicken soup was selected as the food model to assess the effects of the antioxidant complex. The soup contained 3.47% lipid, of which unsaturated fatty acids accounted for a high ratio. The inhibitory effect of the GT50 extract on the oxidation of linoleic acid (LA) induced by continuous heat treatment was evaluated. The oxidation value of LA without GT50 increased after 6 h and reached the maximum value at 12 h, while that of LA with 30 mg% GT50 or 7.5% L-ascorbic acid (Vt.C) were stable for 24 h. Since GT50 showed a synergistic effect with Vt.C at the mix ratio of 2:1 (W/W), the antioxidant complex was developed through a combination of GT50 and Vt.C.