Survival of Listeria monocytogenes in North European type dry sausages fermented by bioprotective meat starter cultures

The survival of Listeria monocytogenes (inoculation 3 log cfu g⁻¹) in dry sausages fermented by bioprotective experimental meat starter cultures Lactobacillus rhamnosus E-97800, L. rhamnosus LC-705 and Lactobacillus plantarum ALC01 as well as Pediococcus pentosaceus RM2000 (commercial control) was studied. In the first trial both experimental and control sausages (pH 5.0–5.2) were L. monocytogenes negative after 21 days of ripening. However, in the second and third trials the experimental sausages were L. monocytogenes negative after 7 days of fermentation while the control sausages were L. monocytogenes negative only after 28 days of ripening. The pH values were typical for North European type dry sausages (pH 4.7–4.9). It can be concluded that while the control sausage fermented by commercial starter culture was listeria-negative at a late stage of ripening process, L. rhamnosus E-97800, L. rhamnosus LC-705 as well as L. plantarum ALC01 expressed additional antilisterial activity resulting listeria-negative North European type sausages at an early stage of the ripening process.