Application of Ice Temperature Storage Technology Assisted by Chlorine Dioxide and Chitosan for the Preservation of Fresh Fish Slices

To solve the problem of fresh fish and meat being prone to spoilage and deterioration during storage and transportation, thus causing great economic losses, we investigated the efficacy based on the synergistic antibacterial effect of chlorine dioxide and chitosan. This paper developed an ice temperature storage technology for the preservation of fresh sturgeon fillets. The research results showed that among the five common different freezing point regulators, only NaCl, glucose, and sucrose displayed negligible effects on the texture of fish slices. The optimal ratio obtained through response surface optimization was 3.07 g/100 mL NaCl, 3.25 g/100 mL glucose, and 4.05 g/100 mL sucrose, which could lower the freezing point of fish fillet to −2.50°C. Based on the changes in volatile base nitrogen, thiobarbituric acid reactants, pH value, and total viable bacteria during storage, the spoilage endpoints of sturgeon fillets stored at ice temperature (−2°C) and low temperature (4°C) were determined to be 9–12 days and 3–6 days, respectively. Based on high-throughput sequencing and traditional culture-isolation techniques, four dominant spoilage bacteria were successfully isolated and identified during stored at ice temperature, including Chryseobacterium sp., Microbacterium sp., Empedobacter falsenii, and Bacillus cereus. For the three components (chitosan, sodium alginate, and poly-L-lysine HCl) of the coating, the response surface optimization results showed that the optimal fresh-keeping ratio was 2.12 g/100 mL of chitosan, 0.72 g/100 mL of sodium alginate, and 1.02 g/100 mL of poly-L-lysine HCl. Under optimal storage conditions, the TVB-N, TBARS, pH, and other parameters in fish meat would be significantly decreased.