In the decade since the U.S. Department of Agriculture (USDA) issued 9 CFR Part 430, “Control of Listeria monocytogenes in Ready-to-Eat (RTE) Meat and Poultry Products; Final Rule”, concern over L. monocytogenes contamination of RTE meat products in retail delis has “blown up.” As evidence of that concern, USDA’s Food Safety and Inspection Service (FSIS) and the Food and Drug Administration (FDA)’s Center for Food Safety and Applied Nutrition (CFSAN) jointly held a public meeting on May 22 in Washington, D.C., to discuss and solicit comments on the draft “Interagency Risk Assessment—Listeria monocytogenes in Retail Delicatessens”, which the agencies had published on May 13. Agency officials said the draft quantitative risk assessment (QRA) “provides… 1) a science-based decision support tool 2) to evaluate the effectiveness of retail practices and interventions to reduce or prevent listeriosis 3) associated with the consumption of RTE foods 4) commonly prepared and sold in the delicatessen of a retail food store. It also examines how changes in current retail practices might further mitigate the predicted risk of listeriosis from these RTE foods.” The agencies are accepting public comments on the draft QRA through July 12, 2013. Deli Meat & Listeria Prevention An FDA notice document stated that “a 2003 industry survey of L. monocytogenes in RTE foods purchased at retail grocery stores showed a seven-fold higher incidence and level of L. monocytogenes in deli meats sliced and served in retail delis compared to those sliced and packaged in manufacturing plants.” One need only observe a supermarket deli on a busy Saturday morning to see a few possible reasons for that higher incidence: any given product may be handled by several employees during a shift, and each slicer is used for many different products. In the best-case scenario, limited segregation of products may occur if department policy dictates using one slicer only for cheese and another slicer solely for meat. Other variables include employee hygiene and the temperature and cleanliness of the deli case. So what’s a supplier to do? “There’s no way for us — or any supplier — to assure product safety once our product reaches the supermarket deli case,” explains Ronald Tew, vice president of operations for Baltimore-based Deli Brands of America. “We simply have to make sure that we’re providing the safest possible product to begin with.” A family-owned, 80-year-old company, Deli Brands of America provides private-label deli meats and value-added prepared entrees to supermarket chains nationwide (with an emphasis on the East Coast). Tew says Deli Brands is known for “doing [flavor profile] customization and for supplying safe, wholesome product.” He adds, “By doing those things consistently, you get a reputation in the industry. As a result, we have a lot of long-term customers that we’ve kept for at least 10 years.” Even so, Tew and Deli Brands President Jeff Saval are well aware that they must continue to offer “the safest possible product” to maintain their reputation and customer loyalty. Toward that end, the company uses a double-barreled approach to control bacteria in their deli meats. After the meat is cooked, finished products are then treated externally with a Listeria-specific bacteriophage product called Listex, in a carrier solution of sodium lactate and sodium diacetate, chemicals that inhibit the growth of multiple pathogens. Tew recalls that when USDA issued the final rule [9 CFR Part 430: Control of Listeria monocytogenes in Ready-to-Eat Meat and Poultry Products; Final Rule] in 2003, “we anticipated that our customers would demand that we use a treatment in the Alternative 1 category. However, few customers even raised the issue and only one chain asked us to use a treatment ‘at least in the Alternative 2 category’ but not necessarily an Alternative 1 treatment.” To comply with the regulation, Deli Brands initially used lauric arginate and a smoke derivative, but that created “issues with our process,” Tew says. Next the company tried injecting sodium lactate and sodium diacetate into the meat products, but that caused flavor issues and increased processing costs substantially. Then, when USDA approved Listex as a processing aid in May of 2011, Tew and his colleagues were able to resolve their dilemma. “We started using Listex about 18 months ago on all of our whole-muscle cooked products,” Tew says. “We found that by using Listex as a surface treatment with sodium lactate and sodium diacetate in the carrier solution, we improved our products’ flavor profile, reduced our processing costs, and significantly increased our shelf life — to as long as 70 days. And because it’s a processing aid, Listex does not have to be listed in ingredient statements, which means we didn’t have to change our product labeling.” Developed by Micreos Food Safety, Wageningen, The Netherlands, Listex is a culture of bacteriophages (or phages for short) that effectively eliminate Listeria monocytogenes. As phages occur in nature, are specific to their target bacterial species, do not affect desirable bacteria in foods or in the human gastrointestinal tract, and do not alter the finished product’s organoleptic properties (such as taste, texture and color), Listex is listed by the Organic Material Review Institute, meaning it can be used in processing of natural and organic foods. Listex is one of the most cost-effective interventions on the market, says Dirk de Meester, Micreos’ business development director. Listeria monocytogenes is one of the most important threats to food safety, due to its high mortality rate (over 20 percent) and the risk it poses to pregnant women. This insidious species can grow at refrigeration temperatures, and as the Food Marketing Institute (FMI) notes in its Listeria Action Plan for Retail Delis, published in November 2012, “Retail delis provide an ideal environment for Listeria due to the types of foods — RTE meats, cheeses, and salads — the moist environment, and temperatures that support growth of Listeria.” FMI’s Listeria Action Plan provides guidance including Standard Sanitation Operating Procedures (SSOPs) for slicers in retail delis, and the final version of the USDA/FDA” Interagency Risk Assessment — Listeria monocytogenes in Retail Delicatessens” will undoubtedly recommend additional steps. In the meantime, some retailers seem to be opting for a simpler path — avoiding the use of slicers. Perhaps in recognition of the food safety and personnel safety challenges associated with having employees slice deli meats on demand, more of Deli Brands’ retail customers have begun purchasing presliced bulk product rather than whole-muscle items. Tew says Deli Brands’ management sees this as an emerging trend; they predict that many retail chains will move away from slicing product to order and will display more small portions on the side of the deli counter. _____ The Food Safety News series on processing aids is sponsored by Micreos. Heidi Parsons is a writer, editor, and content manager for print and online media. During her 15+ years in business-to-business publishing, she has covered food processing, institutional foodservice, packaging, pharmaceuticals, and police canine handling.