Amonrat Thanonkaew, Soottawat Benjakul, Wonnop Visessanguan, E. A. Decker
Frozen squid is susceptible to both lipid oxidation and yellow/brown discoloration during frozen storage. The involvement of lipid oxidation in the microsomal fraction of squid muscle on oxidative rancidity and discoloration was investigated using iron and either enzymatic or non-enzymatic redox cycling pathways. Lipid oxidation was measured by thiobarbituric acid-reactive substances (TBARS), and color changes were measured spectrophotometrically using an integrating sphere. The lipid oxidation was not observed in the squid microsomes in the presence of Fe3+ and β-nicotinamide adenine dinucleotide disodium salt (NADH) or β-nicotinamide adenine dinucleotide phosphate, reduced (NADPH), suggesting that the enzymatic redox cycling pathway was not active. Iron-promoted TBARS formation was observed in the non-enzymatic pathway when ascorbic acid was used as a reducing compound. Non-enzymatic lipid oxidation increased with increasing temperature (4 °C to 37 °C), iron (0 to 100 μM), and ascorbic acid (0 to 200 μM) concentrations. As lipid oxidation in the microsomes or isolated microsomal lipids increased, color changes were observed as could be seen by an increase in b* values (yellowness) and a decrease in a* (redness) values. The ability of iron and ascorbate to promote both lipid oxidation and pigment formation in the microsomal fraction suggests that this pathway could be responsible for quality deterioration of squid muscle during storage.
© 2001-2024 Fundación Dialnet · Todos los derechos reservados