Effects of cold plasma-activated solution on microbial amounts and diversity of Tilapia fillets at refrigerator storage

Abstract

In this study, tilapia fillets were treated with the plasma-activated solution and refrigerated at 4 ± 1 °C. Compared with the distilled water group, plasma-activated lactic acid (PALA) treatment prolonged the microbiological shelf life of fish fillets by 4 d. The total bacterial count, psychrophilic bacteria, Pseudomonas spp., H₂S-producing bacteria, and lactic acid bacteria in the PALA group were lower than those in the other treatment groups (P < 0.05). High-throughput sequencing indicated that Proteobacteria and Firmicutes were the two predominant core microbial phyla present during storage. In the first 5 d of storage, Acinetobacter, Kurthia, and Shewanella were the dominant genera. At the 7th d of storage, the spoilage bacteria Aeromonas and Pseudomonas increased slightly. These mechanistic results demonstrate that cold plasma solution treatment allows tilapia fillets to be stored under refrigeration for up to 7 d. Cold plasma solutions have potential applications in fish fillet refrigeration.