Effect of konjac oligosaccharide and Kappa-Carrageenan on oxidative andstructural changes in silver carp protein induced by fluctuating storage temperatures

Abstract

Two different low molecular cryoprotectants were analyzed in silver carp surimi proteins during different frozen storage conditions (FTC), and a comparison was performed with a conventional cryoprotectant mixture of sucrose (4%) and sorbitol (4%) as positive control (PC). The results showed that a significant decline was noted in sulfhydryl contents (SH), an increase in carbonyl groups, and a surface hydrophobicity due to myosin and protein oxidation. Meanwhile, FTC also altered the stability of secondary and tertiary structures due to the denaturative changes in myofibrillar proteins (MP). Meanwhile, samples that incorporated KC (3%), KOG (3%), and PC showed significant stability in MP against FTC induced changes. This is due to their strong hydrophilic and hydrogen interactions. MP samples containing KOG (3%) demonstrated improved cryoprotective abilities against oxidative and structural changes. Thus, we can recommend KOG as a potential cryoprotectant for maintaining the shelf-life of fish and related products on an industrial scale.