Exploring the impact of cold and modified atmosphere packaging storage on prepared meat products: Temporal dynamics of the bacterial community and quality analysis.

The objective of this paper is to study the impacts of modified atmosphere packaging (MAP) with different gas compositions (70 % O2/20 % CO2/10 % N2;80 % CO2/20 % N2) on quality and dynamic microbial changes of marinated pork chops during the storage period under super-chilled and cooling conditions. Compared with the shelf life of 14 days at 4 °C, the shelf life of prepared pork chops was extended to 56 days at -2 °C storage. The content of carbonyl groups, thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N), and total viable count (TVC) values were significantly reduced (P < 0.05). The super-chilled storage effectively delayed the oxidation of proteins and lipids. The 16srRNA gene amplicon sequencing results showed that the microbial communities of marinated pork chops between -2 °C and 4 °C storages showed a high similarity, except for Serratia, a specific spoilage bacteria in high O2 MAP storing at 4 °C. The gas composition significantly affected the bacterial communities in the different treatment groups (P < 0.05). The spoilage biomarkers in high O2 and high CO2 MAPs were Brochothrix and Leuconostoc, respectively. Significant differences were also observed between high O2 and high CO2 MAPs for the functional potentials based on KEGG, especially for carbohydrate and amino acid metabolism (P < 0.05). The results of this paper provide valuable information for the preservation strategies of prepared meat products.