Effect of ε-polylysine in combination with alginate coating treatment on physicochemical and microbial characteristics of Japanese sea bass (Lateolabrax japonicas) during refrigerated storage

- ε-Polylysine + alginate (PLSA) retarded nucleotide breakdown and lipid oxidation.
- PLSA coating delayed protein degradation, reduced microbial growth.
- PLSA coating maintained better texture and sensory quality of Japanese sea bass.

The combined effects of a novel ε-polylysine/sodium alginate (PLSA) treatment on the sensory and physicochemical characteristics of Japanese sea bass (Lateolabrax japonicas) stored at 4 ± 1 °C for 16 days were investigated. Fish pH value, total volatile basic nitrogen, free fatty acids, K-value, thiobarbituric acid reactive substances, colour, texture, microbiological and sensory quality were measured. Sea bass coated with PLSA maintained flesh colour and tissue hardness, and showed the lower microbial counts, including mesophilic, psychrophilic, enterobacteria, lactic acid bacteria and yeasts compared with the control. In addition, PLSA coating also delayed changes in lipid oxidation, protein degradation and nucleotide breakdown. The results also proved that PLSA coating effectively maintained the sensory quality of sea bass during the storage period. The efficiency was better than that of PL or SA treatment alone. Therefore, the PLSA coating can be applied for preservation of the sea bass to extend its shelf life and improve its preservation quality.