Effects of Antioxidants on Copper Induced Lipid Oxidation During Salting of Grass Carp(Ctenopharygodon idella) Fillets Under Refrigerated Storage

This study was aimed to investigate of the effects of ascorbic acid, citric acid and ethylene diamine tetra acetic acid EDTA with copper in the brine on lipid oxidation of the grass carp (Ctenopharyngodon idella) fillets during 15 days of refrigeration storage. In this study traditional ascorbic acid, citric acid and EDTA solutions (10, 30 ppm) respectively with copper (5ppm) were considered as treatments. Rancidity development was measured by several biochemical indicators including peroxide values and thiobarbituric acid. Also pH expressible moisture NaCl and copper content were measured during 15 days storage. Results showed that primary and secondary oxidation products of control samples were significantly higher than those in other treatments (p<0.05). Also, expressible moisture and pH value of treated sample were showed significant difference during storage. Results showed that all three treatments had significant effect on delaying lipid oxidation (p<0.05) but using of EDTA had the best effect on delaying lipid oxidation and increasing shelf-life of fillets (p<0.05) when similar concentration (10, 30 ppm) of EDTA, ascorbic acid and citric acid were included with 5 ppm copper in the bring EDTA was the antioxidant that effectly inhibited copper-induced lipid oxidation. Key words: Citric acid , EDTA, Ascorbic acid , grass carp, lipid oxidation , copper (11) catalysis