Listeria monocytogenes in Fresh Fruits and Vegetables

Approximately 1600 illnesses and 260 deaths in the United States are caused by food contaminated with Listeria monocytogenes (CDC, 2014; Scallan, et al, 2011). Listeria monocytogenes is a Gram-positive bacterium (Vaquez-Boland, Kuhn et al, 2011) that causes the infection listeriosis within the body. L. monocytogenes can be found in ready to eat (RTE) foods. Unlike other foodborne pathogens, one of the organisms unique characteristics is that it is a psychrotroph, meaning it can grow in refrigeration temperatures; therefore, refrigeration is not the most effective way to control the pathogens growth (figure 1) (Frazer, 1998), even when temperatures almost reach freezing.