Effects of packaging and storage time on lipid and protein oxidation and modifications in texture characteristics of refrigerated grass carp (<i>Ctenopharyngodon idellus</i>) fish muscles

Abstract

Abstract This study aimed to examine the effects of different packaging methods, atmospheric packaging (AP) methods, and vacuum packaging (VP) on the oxidation of proteins and lipids, and the texture characteristics of grass carp fish fillets stored at 4 °C for 8 days. The parameters assessed included lipid, protein oxidation, texture profile, pH, colour, and water-holding capacity. The findings revealed a significant increase (p &amp;lt; .05) in lipid degradation from 0.32 ± 0.02 to 2.08 ± 0.01 mg malondialdehyde (MDA) /kg and protein degradation from 5.60 mg/100 g to a maximum of 29.03 mg/100 g across AP. The total volatile basic nitrogen, thiobarbituric acid reactive substance, water activity (Aw), drip, centrifuging, and cooking loss were much higher in AP compared to those in VP. The total sulphydryl content and texture significantly decreased. Fourier transform infrared spectroscopy analysis showed that protein secondary structure deformation occurred due to oxidation in absorption with peak ranges 1,635.34, 1,518.83, and 1,322.34, respectively, particularly affecting the α-helix, β-sheet, β-turn, and random coil structures. Scanning electron microscopy demonstrated that the microstructure of AP and VP exhibited a reduction in the particle size.