Isolation and identification of Listeria monocytogenes in dairy products
Lovett, J.
Journal - Association of Official Analytical Chemists 71(3): 658-660
1988
ISSN/ISBN: 0004-5756 PMID: 3134338 Document Number: 320437
After an outbreak of listeriosis in Massachusetts (USA) in 1983, the ability of Listeria monocytogenes to survive in raw and pasteurized milk was investigated. An enrichment broth (EB) containing acriflavine, nalidixic acid and cycloheximide was used to eliminate overgrowth of the culture by competing organisms, and a modification of McBride's agar (MMA) was used as the isolation medium. The culture was incubated for 24 h at 30 degrees C. To isolate Listeria from soft cheese, the incubation period was lengthened to 1 wk, and the EB culture was streaked onto MMA at 1 and 7 days. Physical and biochemical patterns, the CAMP test, serological tests and mouse pathogenicity studies were helpful in determining the identity of L. monocytogenes.