The Listeria monocytogenes contamination of meat products

The Listeria monocytogenes (Lm) is repeatedly identified in ready-to-eat foods. Analyses performed on samples taken during state inspections showed unsatisfactory results in 1.8% of cases. Totally 2% of analyses performed on samples taken by food industry operators showed unsatisfactory results. The greatest contamination was found in sea fish (10.8%), followed by delicatessen products (3.4%), meat products supporting the growth of Lm (3%) and fermented meat products (1.6%). Frozen vegetables show consistently high contamination (2.5%). The contamination of raw meat is a significant factor. The Lm was detected in raw meat from sows (36.4% positive samples) and meat from cows (4.8% positive samples), in 1988. Positive results were found in 1.1% of samples taken from the surface of pork shoulder, 1.8% of samples from the surface of leg of pork and 0.6% of samples of mesenteric lymph nodes.