Characterization of the microbial composition and quality of lightly salted grass carp (Ctenopharyngodon idellus) fillets with vacuum or modified atmosphere packaging

The effect of air packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP, 75% CO2/25% N-2) on the composition of the microbial community of lightly salted grass carp (Ctenopharyngodon idellus) fillets stored at 4 degrees C was studied. Physicochemical characteristics (total volatile basic nitrogen (TVB-N) value, pH value and biogenic amines (BA)) were also monitored. Based on sensory evaluation, the shelf life of fillets under AP, VP, and MAP was 8, 16 and 24 days, respectively. High-throughput sequencing showed that Acinetobacter and Pseudomonas dominated the microflora of fresh grass carp. At the sensory rejection time, Pseudomonas and Psychrobacter dominated the AP products. Lactococcus became the predominant genus of both VP and MAP fillets, and there was no obvious difference in the composition of the dominant microbiota between these two treatments at the end of the shelf life.