Characterization of different phenolic acids grafted chitosan and their application for Japanese sea bass (Lateolabrax japonicus) fillets preservation

Abstract

The characterization of chitosan graft different phenolic acids (CS-g-phenolic acids) and the preservation effect on sea bass (Lateolabrax japonicus) was investigated. Caffeic acid (CA), gallic acid (GA) and chlorogenic acid (CHA) were respectively grafted onto CS by carbodiimide coupling method. The results of fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H NMR) and ultraviolet–visible spectrophotometry (UV–vis) indicated that CA, GA and CHA grafted onto CS were successfully. The DPPH scavenging activity and antibacterial diameter of CS-g-phenolic acids were higher than those of CS, illustrating that grafting with phenolic acid effectively enhanced the antioxidant and antibacterial capacity of CS. Meanwhile, the preservation effects of these three CS-g-phenolic acids on sea bass during storage at 4 °C was studied. Results shown that CS-g-phenolic acid could significantly inhibit the growth of microorganisms, reduce the production of total volatile basic nitrogen (TVB-N), prevent lipid oxidation, delay water migration, and maintain good sensory quality of fish fillets during storage. Overall, CS-g-phenolic acid can effectively maintain the quality of sea bass during storage and extend the shelf life of sea bass by another 6 days. These findings will provide a theoretical basis for the application of CS-g-phenolic acids in seafood preservation.