Abstract: This study aimed to reveal changes in the microbial communities in prepared sea bass fillet with beer and the essence of spoilage during partially frozen storage under modified atmosphere packaging for the purpose of providing a theoretical basis for optimizing processing conditions and promoting the product. Illumina MiSeq sequencing technology was used in this study to analyze the diversity of the microbial communities during storage at ?3 ℃ under modified atmosphere packaging in comparison with storage at 4 ℃ under vacuum packaging. The results showed that the dominant microorganisms of prepared sea bass fillets during storage were Firmicutes, Proteobacteria and Bacteroidetes. Vacuum-packaged unseasoned sea bass fillets stored at 4 ℃ showed more abundant microbial diversity than modified-atmosphere packaged prepared sea bass fillets with beer stored at ?3 ℃. On the 4th day of storage, the common spoilage bacterium Brochothrix began to be detected in the unseasoned sea bass fillets, on the 10th day, the abundance of Brochothrix and Pseudomonas rapidly increased, and even Shewanella began to appear, causing complete spoilage of sea bass fillets. The spoilage bacteria Pseudomonas and Shewanella began to appear in modified-atmosphere packaged sea bass fillets with beer on the 20th day. Afterwards, due to inhibition by CO2, the abundance of spoilage bacteria gradually decreased, Pseudomonas grew rapidly towards the end of the shelf life, and Psychrobacte appeared at the end, causing complete spoilage of sea bass fillets. Therefore, the combined application of seasoning with beer, modified atmosphere packaging and superchilled storage can effectively extend the shelf life of sea bass fillets.

Key words: Illumina MiSeq sequencing, prepared sea bass fillets with beer, modified atmosphere packaging, partially frozen storage, microbial community diversity