A Survey of Various Foods for the Presence of Listeria Species.

Various retail foods were analyzed for the presence of Listeria spp. One hundred ten samples of vegetables including lettuce, celery, tomatoes, and radishes, and 14 samples of pasteurized milk, were found to be free of L. monocytogenes . In contrast 9 of 16 (56.3%) chicken legs, 38 of 44 (86.4%) ground meats, and 6 of 30 (20%) fermented sausages contained the organism. Of 530 samples of ice cream products obtained at the manufacturing level, only 2 were positive for L. monocytogenes .