Article Summary:

• Hermetically sealing cheeses, lunch meats, and the like in plastic vacuum packs on your grocer’s shelf may be ramping up the potency of Listeria bacteria 100-fold.
• Listeria is easily killed by cooking, but that doesn’t help when dealing with most cheeses and sandwich meats.
• Simple tips on how to prevent listeria.

Study on Listeria And Plastic Vacuum Packs

As the use of plastic becomes a growing environmental problem, here’s one more reason to avoid buying foods wrapped in plastics. A Denmark National Food Institute concluded a study that indicates that hermetically sealing cheeses, lunch meats, and the like in plastic vacuum packs on your grocer’s shelf may be ramping up the potency of Listeria bacteria 100-fold, turning it into a super killer. The purpose of the vacuum pack, of course, is to protect the food from contamination and to seal it off from oxygen, which can contribute to spoilage — and shorter shelf life. Unfortunately, that oxygen-deprived environment is a bonanza for Listeria monocytogenes, a bacterium that thrives in low oxygen environments and kills 25 percent of the people it infects.

Why Listeria Is A Main Cause of Food Poisoning

Listeria is classified as a so-called “dirt germ” since it is widespread in wastewater, soils, and plants. However, foods of animal origin may also contain Listeria through secondary contamination during processing. And unlike many other food-borne germs, Listeria can grow even in the cold temperatures of refrigerators. The FDA notes that the microbe has been linked with foods such as raw milk; ice cream; soft-ripened cheeses such as feta, Brie and Camembert; hot dogs; raw and deli meats; raw vegetables; raw and cooked poultry; and raw and smoked fish.

As one of the researchers, Tine Licht, said, “Avoiding vacuum packaging would lead to other problems with bacterial growth, so I’m not advocating that.”

Vacuum packaging or not, listeria seems to be on the rise. On March 31, 2017, Italy reported a recall of smoked salmon due to Listeria. Three days after, Austria warned against Listeria in soft cheese. And only two days later, Listeria was found in smoked ham from Denmark.  And according to the CDC, listeriosis affects 1,600 yearly, killing 260.

What to do? How to Avoid Listeria?

Listeria is easily killed by cooking, but that doesn’t help when dealing with most cheeses and sandwich meats. So given the fact that you’re probably going to keep on using vacuum-packed foods, best make sure you keep your immune system optimized and you keep some pathogen killers on hand to use at the first sign of food poisoning. Symptoms usually show up 2-30 days after exposure and may include flu-like symptoms such as headache, muscle aches, nausea, fever, and vomiting.  However, older adults and people with immunocompromising conditions may experience a more invasive infection such as sepsis, meningitis, and meningoencephalitis–which can be fatal.  In fact, mortality rates are higher with Listeria than salmonella infection.  And it can even cause premature births or miscarriages in women.

Another solution is to try and limit plastic-wrapped, packaged foods. If you do buy vacuum-packed foods, be sure to kill the listeria buy cooking it at high heat, a minimum of 165F, or 74C–especially meat. Also be sure the juices from the meat packages do not get on other foods and wash your hands thoroughly when handling deli meat.

As for foods you don’t typically cook, you could simply reduce your deli meat and dairy products.  Besides, as we have discussed in previous articles, deli meats are linked to cancer and dairy may contribute to rheumatoid arthritis, diabetes, autoimmune diseases, cancer, and more.  Bottom line: minimizing deli meats and cheese may save both your health and the planet.