Listeria: Get the Facts
Learn how to prevent Listeria contamination in food manufacturing with rigorous sanitation, environmental monitoring, good design, and cross-contamination control.
Listeria infection is the third leading cause of death from foodborne illness in the United States.
What is Listeria?
Listeria is a type of bacteria that can cause a serious infection called listeriosis. Unlike many other foodborne bacteria, Listeria can grow even in refrigerated temperatures, making it a particular concern for food safety.
It's found naturally in soil and water and can be carried by animals, meaning it can easily contaminate various foods, especially raw produce, unpasteurized dairy products, and deli meats. While healthy individuals might only experience mild, flu-like symptoms, Listeria poses a significant risk to pregnant women, newborns, the elderly, and those with weakened immune systems.
Listeria often hides in cracks and crevices on surfaces and equipment, leading to cross-contamination of ready-to-eat foods.
Prevention
The best way to prevent listeriosis is through careful food handling, thorough cooking, and avoiding high-risk foods if you are in a vulnerable population.
4 simple steps to help prevent Listeria In food manufacturing
Maintain rigorous sanitation and cleaning programs: Listeria can form tough, hard-to-remove biofilms on surfaces. Regular, thorough cleaning and sanitizing of all food contact and non-food contact surfaces, including floors, drains, walls, and equipment, is essential. This often involves using appropriate detergents and sanitizers, and disassembling equipment for deep cleaning.
Implement effective environmental monitoring: Regularly test surfaces (both food-contact and non-food-contact) for the presence of Listeria species. This "seek and destroy" approach helps identify potential harborage areas and contamination pathways early, allowing for targeted corrective actions before Listeria can spread to food products.
Practice good hygienic design and maintenance: Design facilities and equipment to minimize areas where Listeria can hide and grow, such as cracks, crevices, or standing water. This includes using seamless materials, proper drainage, and equipment that is easy to clean and inspect. Regular maintenance to address any damage or wear is also crucial.
Control cross-contamination and traffic: Establish strict zoning within the facility to separate raw materials from ready-to-eat (RTE) areas. Implement practices that prevent the transfer of Listeria from one area to another, such as dedicated equipment, color-coded tools, and controlled personnel movement. Employee training on proper hand hygiene, gowning, and traffic patterns is also vital.