The latest investigation by California HealthCare Foundation Center for Health Reporting’s Deborah Schoch will make you think twice before ripping into a sack of spring mix, but her work about the myriad food safety challenges posed by bagged salads examines the industry’s struggle to develop technology powerful enough to overcome the existential threat posed by E. coli and friends.
The industry has made great strides since a 2006 outbreak linked to tainted spinach, she writes, but “It’s impossible to stop all pathogens from landing on lettuce and spinach leaves.” And once they’re on the leaves, it seems as if their spread is almost inevitable. They hide in gooey biofilms and resist powerful washes.
Thousands upon thousands of salad leaves are taken to a central plant, washed together, bagged and shipped. Even if only a few leaves are tainted, harmful pathogens can spread in the wash water — the modern salad version of the old adage that one bad apple spoils the whole barrel.
“I would think of it as swimming in a swimming pool in Las Vegas with a thousand people I didn’t know,” said William Marler, a prominent Seattle-based food safety attorney.
Plenty of public and industry money has been aimed at the problem, Schoch writes. “The Center for Produce Safety at UC Davis, founded in response to the spinach outbreak as an industry-public partnership, has pumped more than $9 million into 54 research projects at 18 universities.”
Even the best research can’t reduce the risk of contaminated greens by 100%, scientists said. At Earthbound, Daniels says the ultimate goal is to achieve what scientists call a “5 log reduction,” the equivalent of pasteurizing milk. In short, if an unwashed lettuce contained 100,000 pathogens, the perfect wash system would knock off five “0s” and reduce the pathogen count to 1.
An added bonus? Schoch’s column on whether she (and the experts she talked to) feel like it’s important, or even salutary, to wash their bagged greens.