[Multiplication of Listeria in milk products].

The results of the evaluation of the multiplication dynamics of Listeria cells in milk and Bifidok, a lactic acid product, are presented. The samples were inoculated on thioglycol agar and studied at different exposure time after incubation at 37 degrees C, 20 degrees C and 4 degrees C. The study revealed the intensive multiplication of Listeria cells in milk, also during storage in a household refrigerator. The presence of bifidobacteria mixed with kefir-producing culture in dairy products was shown to essentially inhibit the growth of Listeria cells which were not detected by bacteriological techniques on day 7.