Sorry to all you spinach fanatics out there, but even the stuff you wash can contain some scary bacteria, including: Escherichia coliaccording to research presented at a recent meeting of the American Chemical Society.
You’re probably worried about food poisoning when cooking raw meat, but what about produce? According to the Centers for Disease Control and Prevention, 48 million Americans suffer from foodborne illnesses each year, and half of those illnesses are caused by fresh produce.
Dr. Sharon Walker, a professor of chemical and environmental engineering at the University of California, Riverside, decided to study pre-washed spinach after experts conducted a study at the University of California in 2006. Escherichia coli Bacterial outbreak (resulting in 205 confirmed infections and 3 deaths).
Walker used microscopy techniques to observe bacteria on the surface of the spinach and counted the number of bacterial cells that stuck to and detached from the spinach after cleaning with various strength bleach rinses. And while a highly concentrated rinse solution (commonly used commercially) killed all the bacteria, Walker said the spinach leaves’ bumps, nooks and crannies were exposed to the bleach rinse solution. We found that this caused an uneven distribution. This resulted in up to 90 percent of the bacteria surviving on some spinach.
If bacteria are not completely killed, they can grow and spread to surfaces in processing facilities or cross-contaminate other leafy vegetables before they reach the supermarket.
“This is completely consistent with what we know about lettuce and other leafy greens,” says food safety expert Dr. Benjamin Chapman. “There are similar studies that have shown that food has bacteria on it and that three washes or a home wash probably won’t remove the bacteria.”
Hmm, that’s right. Does that mean I should stop eating leafy greens?
“I’m not trying to scare anyone away from eating spinach,” Walker says. “The industry is working hard to minimize risk and keep produce as clean as possible.”
To keep vegetables as clean as possible, store them in the refrigerator below 41°F and consume them within 3 to 4 days of opening the package.
