Aside from the produce section, the deli and salad bar areas of the grocery store are perhaps the most visually interesting. From a food-safety standpoint, though, the deli counter in particular can be full of pitfalls.
In the deli case, the large, plastic-wrapped chunks of deli meat waiting to be sliced are called “chubs.” They are made by using sodium phosphate, sodium alginate, or other ingredients or processes to bind meat together inside the casing. Those additives are safe, except that they add more salt to the product.
Those chubs are made with fully cooked meat, but still could be contaminated. The key pathogen in deli meat—Listeria monocytogenes—may come from the meat or from the environment around it. Listeria can live and thrive on plastic, on metal, and in water—that’s why the same nasty bug can grow on cantaloupe-washing machinery and contaminate melons. So it’s not that the contamination is always on the meat—but if it’s on the slicer or in the case where the meat is cut and handled, the bacteria can jump to the meat and come home with you. Even with thorough cleaning (and most grocery stores are required to clean their equipment several times a day), Listeria may survive and continue growing. Once the bacteria are well-established in a slicer or butcher case, they can be almost impossible to clean out—some retailers have had to rip out entire deli cases to eliminate Listeria.
Listeria can be dangerous even if you’re healthy, but they pose a special threat to a pregnant woman or someone who is immune-compromised; the bacteria can cause severe illness in people who are immune-compromised and can cause miscarriage or stillbirth in pregnant women. Thus pregnant women should avoid fresh sliced deli meat.
Listeria bacteria are, of course, invisible to the naked eye, so you should take precautions. First, check to see if the food handlers behind the deli counter are wearing plastic gloves. They should be snapping on a new pair after they handle each chub, to avoid passing bacteria from chub to gloves to another chub. They should also be using paper sheets on the scale and the deli slicer, to keep meat from touching those metal surfaces where bacteria might be lurking.
Whether you are ordering sliced turkey, ham, or specialty meats such as prosciutto, purchase only what you can use in three days or less. Deli meat, once the chub has been opened and sliced, has an extremely brief shelf life, because bacteria that may be present at low levels can, over time, multiply and become increasingly dangerous.
Prepackaged deli meat has a lower risk of being contaminated by Listeria because it is not handled in the retail environment. Hence, it won’t be contaminated on the slicer, by a worker, or while in the deli case. Pregnant women should still avoid packaged deli meat or reheat it to steaming before eating, just in case it was contaminated during processing or the package was cross-contaminated in transportation or storage. For other consumers, once you open the package at home, the clock starts ticking on the three-days-till-discard rule.
Anything, even cheese and other non-meat items, that comes out of the deli case can come with Listeria, so you need to practice the same defensive eating tips with those items. Deli cheese should never be sliced on the same equipment used to slice meat— talk to the manager if you see a retail worker violating that rule.
Other relevant links:
- Our guide to your supermarket’s deli. See: Are You Sure You’re Buying Safe Deli Meats?
- Follow these food safety tips to keep your family healthy. See: Food Safety Tips for Packing and Unpacking Your Food
- Here are a few things to consider before diving into the salad bar. See: Food Safety at the Salad Bar