Isolation and Identification of Lactobacillus sakei from Fermented Mandarin Fish and Its Application in Fermented Mandarin Fish

A Lactobacillus strain named SMF-L5 from traditional fermented mandarin fish was isolated using MRS medium with bromocresol green and identified as Lactobacillus sakei by morphological, physiological and biochemical assays and 16S rDNA sequence analysis. L. sakei SMF-L5 grew well in MRS liquid medium, entered the stable growth period after 14 h, and produced the highest viable cell count of 7.0 × 10⁹ CFU/mL. The production of lactic acid of the strain was 10 g/L after 24 h cultivation. The optimal culture conditions were as follows: culture temperature 30.9 ℃, initial pH 6.15 and inoculum amount 1.94%. Strain SMF-L5 had tolerance to 0.08 g/mL NaCl, and obvious inhibitory effects on Escherichia coli, Staphylococcus aureus. The fermented mandarin fish inoculated with L. sakei SMF-L5 had superior color, texture and flavor than spontaneously fermented mandarin fish. These results showed that L. sakei SMF-L5 has the potential for application as an excellent starter in the industrial production of smelly mandarin fish.