Evaluation of antioxidant level and protein oxidation of rainbow trout (Oncorhynchus mykiss) fillets during rigor and post‐rigor

Abstract

In this study, the relationship between stunning techniques and protein oxidation which are accepted as the main cause of food spoilage was investigated. For this purpose, the antioxidant status, in vivo myofibrillary protein (MP) oxidation and sensitivity, and postmortem oxidation (inducted with hydroxyl radical system) of rainbow trout (Oncorhynchus mykiss) fillets killed by hitting to head (T1), neck crushing (T2), and convulsion (T3) methods, were investigated. Statistically significant differences (p < .05) were found among all parameters examined and it was observed that the most stressing technique was the convulsion method. It was determined that in protein profiles myosin were influenced too much from stunning technique and in actin observed oxidation-induced reductions. Reductions in S-S and S-H were also found to be increased in carbonyl concentrations, but the most effective values in both processes were determined by the convulsive technique. Our results show that shortterm stunning techniques (hitting to head, neck crushing) give better meat quality results in terms of O. mykiss welfare and low MP oxidation rates. In general, we can say that T3 group fillets are more sensitive to oxidative damage, while T1 and T2 groups give better results in maintaining meat quality with low MP oxidation rates.

Effect of climate change on fillet quality and shelf‐life of Oncorhynchus mykiss under controlled conditions

“…This situation is attributed to impaired antioxidant enzyme activity increasing the likelihood of oxidation of disulfide bonds and thereby reducing the concentration of -SH. 15 However, direct oxidation of protein side chains has been reported to be responsible only for carbonylation in meat proteins. 45 Cheng et al 46 reported protein oxidation in terms of carbonyl content in sarcoplasmic and MPs of dried chopped pork slices and conversion of -SH groups into S S groups during thermal treatment.…”

“…The fish had previously been killed using a common killing technique described by Işık et al 15 The analysis was conducted taking into account the period in which rigor would occur. The glycogen level was determined spectrophotometrically as 620 nm within the first 6 h using a commercial kit (Abcam, Glycogen Assay Kit, www.soci.org G Alak et al…”

“…Cambridge, MA, US) using the KOH/anthrone method from the moment rigor occurred and was expressed as mg glycogen/g muscle. 15 The concentration of lactic acid was determined using a commercial kit (ChemBio, CB55560, İstanbul, Turkiye) from the moment the muscle tissue began to develop stiffness (within the first 6 h).…”

Ulexite modulates the neurotoxicological outcomes of acetylferrocene‐exposed rainbow trout

“…Biochemically, there is an increment in the toxic mechanism of movement because of the affinity between metals, so the sulfhydryl groups (–SH) attack heavy metal‐containing cations or molecules. The resulting metal‐SH bond may affect the enzyme, causing loss of its catalytic activity (Isık et al, 2020; Marins et al, 2019). When large numbers of ROS are stimulated, oxidative stress can be triggered as a harmful biological reply.…”

The effect of multiple freeze–thaw cycles on protein oxidation and quality of Trachurus murphyi

“…Protein oxidation has been deemed as a major contributor to the deterioration of fish (Zhang, Shan, et al, 2020).Deterioration of fish quality may occur under degradation, denaturation, or aggregation of proteins during transportation and storage. Several studies have reported the changes in the structure and physicochemical properties of myofibrillar protein during storage, suggesting that protein denaturation is a major contributor of shelf-life decline, nutrient loss, and structural changes in fish (Alak et al, 2021;Isık et al, 2020). Protein oxidation is a complicated phenomenon that involves amino acid residues, buried hydrophobic exposure, and protein unfolding upon heating (Dericioglu at al., 2019).…”