ARROW Scientific the 3M Petrifilm environmental listeria plate method. It is designed to detect listeria in food processing plants.
It delivers results within 28 hours of sampling. With traditional off-site testing, listeria has a three to five-day head start while environmental samples are processed.
The plates cost less than traditional methods and use the familiar Petrifilm design. Sample preparation is fast and easy. Interpretation is similar to other 3M Petrifilm plates and there are no complicated techniques or time-consuming training requirements.
Traditional listeria testing methods provide you with a single detected/not detected result. The new plates can provide this type of qualitative result, or a semi-quantitative result showing relative levels. They can also provide quantitative showing the actual listeria count. The test allows food plants to develop baselines, monitor trends and keep tighter surveillance on hot spots.
Most testing methods for environmental listeria require an enrichment process, in which listeria multiply to high concentrations. Because the plates do not require enrichment, the risk of contamination is reduced and allowing results to be available in 28 hours. Listeria only grows under the film on the EL plate where it is contained and easily disposed of.