Listeria monocytogenes can be found in most environments, but is a particular problem in delicatessens. Food Poisoning Bulletin has told you about many recalls of deli foods for contamination by this pathogenic bacteria. Listeria is often associated with ready-to-eat deli meats and soft cheeses that may be recut and packaged by store delis.
And studies have shown that Listeria can easily survive the standard cleaning procedures used by most deli operators and employees. The bacteria can survive at refrigerator temperatures and can hide in nooks and tiny crevices. In fact, pregnant women and people with compromised immune systems are told to avoid eating ready-to-eat foods purchased from delicatessens.
The USDA’s Food Safety and Inspection Service (FSIS) held a webinar on January 13, 2016 to discuss how to control Listeria monocytogenes in the retail environment. A risk assessment showed that “more than 80% of Listeria illnesses associated with ready-to-eat meat or poultry products sold at delis (i.e., deli meat) were attributed to product sliced or otherwise handled at the retail store.” There is zero tolerance for Listeria bacteria in food products.
And the Agency is going to launch a year-long nationwide pilot project to assess whether retailers are using the best procedures and methods to control Listeria bacteria. The rules for managing this control are called “Best Practices Guidance for Controlling Listeria monocytogenes in Retail Delicatessens.” FSIS Compliance Investigators will fill out questionnaires on whether retailers are following specific cleaning and sanitizing recommendations from the guidance.
Best practices include maintaining deli products under sanitary conditions so Listeria cannot adulterate the food, and using a self-assessment tool to understand if the practices they are using are sufficient. New practices can be adopted to control Listeria growth.
The guidance documents state that food processing equipment should be dissembled during cleaning and sanitizing. Retailers must scrub surfaces during cleaning to prevent biofilm formation that can shelter the bacteria and make it impervious to sanitizing products. And retailers should rotate the types of cleaners and sanitizers they use to provide Listeria bacteria from becoming established in the area. Listeria is a “harborage organisms”, which means that it can form niches and grow to high numbers.
The CDC estimates that listeriosis, the infection caused by this bacterium, sickens 1,600 Americans every year. Of those people, 1,500 are hospitalized and 260 people die. The bacteria causes a high level of deaths compared to other foodborne pathogens.
The Interagency Retail Listeria monocytogenes risk assessment yielded key findings about controlling this bacterium. If all refrigerated ready-to-eat foods are stored at 41°F or below, about 9% of predicted Listeria cases could be prevented. In addition, if all deli products that support this bacteria contained growth inhibitors, 96% of predicted listeriosis illnesses could be prevented. Unfortunately, the concentrate of growth inhibitor used may not be high enough to work throughout the shelf life of the product, and these chemicals affect the food’s flavor.
Cross-contamination is a problem in delis. Slicers are key sources of cross-contamination, and product handling, cleaning, sanitizing, and glove use can help prevent it. In addition, eliminating environmental niches in the deli area will help reduce the risk of cross-contamination. And sanitation practices reduce the predicted risk of illness.
FSIS will analyze the information gathered on these questionnaires quarterly. Results will be published at the FSIS web site.