PREVENTION OF SARDINE LIPID OXIDATION BY ANTIOXIDATIVE MAILLARD REACTION-PRODUCTS PREPARED FROM FRUCTOSE-TRYPTOPHAN

The development of antioxidative effect due to the Maillard reaction between L-tryptophan and D-glucose was found out to be closely related to the degradation of fructose-tryptophan (FT), an Amadori compound formed from these substrates. Therefore, FT was synthesized and used as a starting material for the Maillard reaction in this study. The antioxidative effect was developed by the decomposition of FT itself, while the extent of the antioxidative effect development was accelerated by the addition of free tryptophan. During the Maillard reaction of FT with tryptophan or glucose, FT degradation followed the first order reaction, whereas developments of brown color and fluorescence were the zero order reaction. The Maillard reaction products (MRP), which had the most potent antioxidative effect in this study, were used as an antioxidant for the prevention of sardine lipid oxidation. It was revealed that MRP effectively inhibited the oxidation of sardine lipid and had a synergistic effect with alpha-tocopherol.