A press release issued by MSU proposes the idea that bagged pre-washed salads may be a game of chance, there the odds are not in the consumer’s favor.
Prewashed packaged vegetables, like the spinach that is the focus of the recent outbreak of E. coli, always have been viewed with suspicion from experts in foodborne illness because it’s a packaging system that inherently increases the risk of spreading germs.
Thomas Whittam, Michigan State University Hannah Distinguished Professor of microbial evolution, says that the combination of E. coli’s durability and power with a mixture of produce creates the potential for a veritable “stew” of food poisoning.
"When a contaminated plant gets mixed in with hundreds of other plants and packaged together, and when it takes very few bacteria to get sick, that really increases the risks," Whittam said. "With washing you can remove 99.99 percent of the bacteria, but the few that make it through don’t get killed by normal defenses in the stomach. Basically, you’re assuming a lot of risk."