Effects of phenolic acid grafted chitosan on moisture state and protein properties of vacuum packaged sea bass (Lateolabrax japonicus) during refrigerated storage

Abstract

The aim of this study was to investigate the effects of chitosan-grafted-phenolic acid (CS-g-phenolic acid) on moisture state and protein properties of vacuum packaged sea bass (Lateolabrax japonicus) fillets during refrigerated storage. Results showed that CS-g-phenolic acid could significantly lower drip loss and cooking loss, and efficiently delay the changes of water activity (Aw) and water migration. TCA-soluble peptides, protein solubility, myofibril fragmentation index (MFI), surface hydrophobicity and SDS-PAGE results revealed that graft copolymer treatment could reduce the protein oxidation and degradation of sea bass during refrigerated storage. Meanwhile, the results of intrinsic fluorescence intensity (IFI) and scanning electron microscope (SEM) showed that the graft copolymer could maintain the structure of fish. Therefore, the graft copolymer coatings combined with vacuum packaging could effectively inhibit the water loss and protein degradation of sea bass fillet during refrigerated storage.