Many foods have been associated with L. monocytogenes, especially when they’re in raw form. Prime examples include ready-to-eat processed products, poultry and meats, vegetables, seafood and improperly or unpasteurized milk, cheeses (particularly soft varieties) and ice cream. Contamination can come from these raw materials, from the air, food workers, and food-processing environments. Certainly, control of Listeria species, including Listeria monocytogenes, is vital. Food processors mustn’t let their guard down to test for this persistent pathogen, methodically sampling end product and key areas within food production environments as well as other food contact and non-food contact surfaces in plants that could be reservoirs for Listeria. They also must be mindful of the fact that L. monocytogenes can grow in refrigerated temperatures.
To assist these critical efforts, food producers count on technology to potentially grow selective organisms like Listeria monocytogenes to detectable levels while simultaneously preventing less harmful microorganisms from also growing and interfering with accurate testing. Then they must evaluate its presence and prevalence.