Abstract: This study aimed to explore the differences in the carbon source utilization and kinetic parameters of the dominant spoilage bacteria in fresh Pseudosciaena crocea stored at different temperatures. At 5 and 25 ℃, the shelf life was determined by sensory, physical and chemical indicators. MIDI gas chromatography was used to preliminarily identify the spoilage bacteria isolated, and the dominant spoilage bacteria were determined through changes in the microflora and they were identified up to species level by 16s RNA gene sequencing. The difference in their carbon source utilization profiles were measured by Biolog system, and the carbon source utilization curves were fitted to the Gompertz equation to obtain the kinetic parameters. Results showed that the shelf-life of fresh P. crocea at 5 ℃ was (9.0 ± 1.0) days, while at 25 ℃ the shelf life was (1.0 ± 0.11) days. The dominant spoilage bacteria were Shewanella putrefaciens and Vibrio fluvirus at 5 and 25 ℃, respectively. The average carbon utilization efficiency at 5 ℃ was lower than that at 25 ℃; the average well color development (AWCD) of S. putrefaciens at 5 ℃was higher than that of V. fluvirus, while the opposite was observed at 25 ℃. At 5 ℃ S. putrefaciens mainly utilized monosaccharides, polysaccharides, carboxylic acids, and esters while V. fluvirus mainly utilized monosaccharides, polysaccharides, amino acids and carboxylic acids, and at 25 ℃ S. putrefaciens and V. fluvirus mainly utilized monosaccharides, polysaccharides, amino acids and carboxylic acids. Conclusion: Temperature affected the carbon utilization efficiency of spoilage bacteria and the carbon source utilization efficiencies of different spoilage bacteria were different. By adjusting temperature, carbon source substrate and other environmental factors the spoilage bacteria can be inhibited, thereby extending the shelf life of fresh P. crocea.

Key words: fresh Pseudosciaena crocea, dominant spoilage bacteria, carbon source utilization