Effects of autochthonous Lactobacillus plantarum strains on Listeria monocytogenes in sucuk during ripening

The aim of this study was to investigate the effects of autochthonous Lactobacillus plantarum strains (S50, S51, S72, S74, and S85) as starter cultures on growth of Listeria monocytogenes in sucuk (Turkish dry fermented sausage) production. The counts of L. monocytogenes, lactic acid bacteria, and Enterobacteriaceae as well as pH value and moisture content were determined in sucuk during ripening period. L. monocytogenes, lactic acid bacteria, and pH value were significantly affected (p < 0.01) by both starter culture and ripening period. A slight increase in L. monocytogenes count was observed in the control group whereas a reduction was observed in samples produced with L. plantarum strains at the first day of fermentation. Although L. monocytogenes reduction in control group with spontaneous microbiota was 0.54 log cfu/g after 11 days of ripening, reductions of as high as 2.74 log cfu/g was observed in the presence of L. plantarum S50. Practical applications: In the current study, five different autochthonous Lactobacillus plantarum isolates were identified, the effects of these strains on the behavior of Listeria monocytogenes in Turkish fermented sausage (sucuk) were determined. To the best of our knowledge, this is the first report investigating the effects of autochthonous lactic acid bacteria strains on behavior of L. monocytogenes in sucuk fermentation. As starter culture autochthonous lactic acid bacteria can be more competitive than commercial types. Our findings reveal the importance of the use of these autochthonous L. plantarum strains causes rapid pH drop to inhibit L. monocytogenes growth during sucuk fermentation. And also L. plantarum S50 strain may be more suitable for use as bioprotective culture or starter culture compared to other strains.