EN
The following paper includes the results of research, concerning the occurrence of Listeria spp in salted herring and herring salads. 100 samples of traditionally and vacuum packed herring and 40 herring salads were examined. It was established that 6.6% of the samples were contaminated with these microorganisms. 4 strains of Listeria innocua and 5 strains of L. monocytogenes were isolated. Listeria was not found in the herring salads, which was explained by the low, <4 pH of the product. Moreover, the ability of Listeria monocytogenes to develop in the environment of salted herring was determined. It was established that the pathogenic microorganisms multiplies in the herring, stored at the room temperature. At 10°C the development of Listeria is totally inhibited. Sodium benzoate has little influence on the development of Listeria because it merely delays the beginning, of the logarithmic phase of the bacteria development by 2 days.