Review. Specific detection of Listeria monocytogenes in foods using commercial methods: from chromogenic media to real-time PCR

Listeriosis is one of the most important food-borne diseases. A variety of culture and rapid methods are available for the detection of Listeria spp. in foods. Although the presence of L. innocua may indicate potential contamination with L. monocytogenes, only the latter species is pathogenic for humans. Therefore, the most adequate tests are those which specifically detect L. monocytogenes. Chromogenic media is currently the most common method used for the presumptive identification of L. monocytogenes. Some tests like those based on antigen detection are fast and easily applied, but only a few may specifically detect L. monocytogenes. Real-time polymerase chain reaction is increasingly applied in food diagnostics for the detection of L. monocytogenes due to the availability of different specific commercial test methods. Microarrays and biosensors are some examples of new technologies that might be used routinely for the detection of L. monocytogenes in foods in the future.