A recent study carried out environmental monitoring programs (EMPs) for Listeria monocytogenesat three food production facilities in Japan with the aim of developing EMPs that are relevant to Japanese food businesses and to encourage more widespread adoption of EMPs.
Research was conducted in 2021–2022 at two side dish manufacturing plants and one meat processing facility. EMPs for Listeria were divided into three areas: a dirty area in which raw materials were handled, a semi-clean area in which raw materials to be cooked and heated semi-finished products were mixed, and a clean area in which items were handled after cooking. The sampling locations were further divided into four zones: Zone 1, in direct contact with food; Zone 2, not in direct contact with food but close to food or food contact surfaces; Zone 3, remote to food or food contact surfaces inside the food processing area; and Zone 4, not in direct contact with food, outside the food processing area.