Changes in physicochemical properties of silver carp (Hypophthalmichthys molitrix) surimi during chilled storage: The roles of spoilage bacteria

•P. gessardii, A. media, and A. johnsonii were dominant bacteria during chilled surimi storage.•Bacterial contributions to the physicochemical properties of chilled surimi were evaluated.•P. gessardii has a strong ability to degrade protein.•Cadaverine mainly came from A. media. Chilled surimi has become increasingly popular owing to its superior texture and freshness. In this study, changes in the microbiota and gel properties during chilled surimi storage, and the contributions of dominant bacteria to the physicochemical properties of chilled surimi were investigated. The results showed that Pseudomonas gessardii, Aeromonas media, and Acinetobacter johnsonii were the dominant bacteria during chilled surimi storage. P. gessardii was the key bacteria that degraded protein in the process of surimi spoilage, which led to high total volatile base nitrogen (TVB-N), trichloroacetic acid (TCA)-soluble peptides as well as poor gel properties. Both P. gessardii and A. media were high putrescine producers, whereas only A. media produced cadaverine. In this study, spoilage microorganisms in chilled surimi were investigated for the first time, and it was found that P. gessardii had the greatest influence on surimi quality, which provides a research basis for in-depth study on the mechanism of microbial spoilage and the preservation of chilled surimi.