Screening of autochthonouslactic acid bacteria and optimization of fermentation process in low-salt Zhayu of red rice

Objective: To solve the problems of an uncertain fermentation process, a long fermentation period, and the unstable quality of traditional naturally fermented preserved fish. Methods: The lactic acid bacteria were isolated from low-salt preserved red fish, and the inhibition ability, salt tolerance, and acid production ability of the strains were investigated. The lactic acid bacteria suitable for fermentation were screened out, and the fermentation of preserved red fish was intensified by inoculation. The amount of red rice flour added, the amount of salt added during curing, and the fermentation temperature were optimized in the fermentation process. Results: There were 22 strains of Pediococcus with inhibitory effect on Escherichia coli or Staphylococcus aureus were isolated, among which Pediococcus pentosaceus P-56 had the best inhibitory effect on Escherichia coli and higher tolerance to bile salt and acid; After inoculation fermentation and process optimization. The pH value of the Zhayu decreased to 4.42 at 4 days of fermentation, the TCA-soluble peptide content was 434.99 μmol/g and the sensory score reached 45.7. Conclusion: The optimal process conditions for the fermentation of preserved red fish with lactic acid bacteria were: 4% salt addition for curing, 4% red yeast rice flour addition and fermentation temperature of 32 ℃.