Effect of different stunning methods on antioxidant status, in vivo myofibrillar protein oxidation, and the susceptibility to oxidation of silver carp (Hypophthalmichthys molitrix) fillets during 72 h postmortem

Abstract This study aimed to evaluate the effects of different stunning methods (percussion, T1; immersion in ice/water slurry, T2; gill cut, T3) on antioxidant status, in vivo myofibrillar protein (MP) oxidation, and the susceptibility to postmortem oxidation (induced by hydroxyl radical oxidizing system) of silver carp ( Hypophthalmichthys molitrix ) fillets. Stress conditions, antioxidant enzyme activities, and protein oxidation parameters were analyzed during 72 h postmortem. The results indicated that the strongest stress conditions in the T3 group led to impaired glutathione peroxidase (GPx) and total superoxide dismutase (T-SOD) activity, and significantly ( P in vivo MP oxidation of fillets. The T3 group also showed severe losses in myosin heavy chain (MHC) intensities and sulfhydryl groups at higher H 2 O 2 concentrations. Overall, fillets from the T3 group were more susceptible to oxidative damage, and the T1 and T2 groups maintained better quality in terms of lower MP oxidation rates.