Abstract: Microbial spoilage is one of the most important causes of decline in the quality of aquatic products during processing and storage. In order to elucidate the microbiota composition and quality of Penaeus vannamei treated by chitosan-tea polyphenols composite during refrigerated storage, shrimp samples were treated with 3 g/100 mL chitosan + 3 g/100 mL tea polyphenols (CP), and 3 g/100 mL chitosan (CH), 3 g/100 mL tea polyphenols (TP) or sterile water (CG) and then stored at 0 ℃ for 8 days. The microbial flora was investigated by high throughput Illumina-MiSeq 16S rRNA sequencing, and changes in sensory attributes, total volatile basic nitrogen (TVB-N) content, ATP complex content, K value, biogenic amine content and total viable count (TVC) were measured. The sensory shelf-lives of CG, TP, CH and CP treatments were 5, 7, 7 and 8 days, respectively. At the end of shelf life, Pseudoalteromonas, Candidatus Bacilloplasma and Psychromonas were the dominant spoilage bacteria in CG treatment, while Pseudoalteromonas, Psychromonas, Candidatus Bacilloplasma and Aliivibrio were the dominant spoilage bacteria in CP treatment. Aliivibrio, Moritella and Pseudoalteromonas were the dominant spoilage bacteria in both CH and TP treatments. The preservative treatments affected the microbiota and consequently chemical quality attributes. Compared with CH and TP, CP showed lower TVB-N, putrescine, cadaverine and hypoxanthine contents over the entire storage period but higher contents of inosine 5’-monophosphate and hypoxanthine riboside at the late stage of storage. In conclusion, chitosan-tea polyphenols composite preservative altered the microbiota composition and delayed quality deterioration of P. vannamei during refrigerated storage at 0 ℃.

Key words: Penaeus vannamei; chitosan-tea polyphenols composite; microbiota composition; quality; biogenic amine