Inhibitory effect of citric acid on rancidity of frozen catfish (Silurus glanis)fillets

The effect of aqueous solution of citric acid (CA) on the lipid stability of the European catfish (Silurus glanis) fillets during frozen storage (up to 6 months) was investigated. Rancidity development was measured by several biochemical indices (free fatty acids, peroxides and TBA) and complemented by the measurement of expressible moisture and sensory evaluation (flesh odor, consistency and flesh appearance). The CA treatment led to some lower free fatty acids (6.43% oleic acid in total lipid at month 6), peroxides (7.98meq oxygen/kg lipids, at month 6) and secondary compounds formation (2.16mg malondialdehyde/kg fish sample). Lower peroxide, thiobarbituric acid-reactive substance (TBA), free fatty acids (during 0,3 and 6 months frozen storage), and expressible moisture (month 6) values were obtained from CA-treated fish fillets than the untreated (blank control) ones (p<0.05).