A South Carolina TV station recently had 15 different salad bar items tested for pathogen contamination, and while lab results indicated that no E. coli, Listeria or Salmonella were present, relatively high numbers of microbes and total coliform bacteria were.
WMBF in Myrtle Beach, SC, shipped a cooler packed with samples of four types of items collected from open salad bars at four unnamed local grocery stores to IEH Laboratories near Seattle via overnight delivery. The items in the cooler included leafy greens, raw vegetables, cooked meats and mayonnaise-based salads.
Besides the three major pathogens mentioned above, the station reported that the lab tested for the number of microbes in one gram of food, and those results weren’t negative. In fact, the leafy green samples all had more than 1 million colony-forming units per gram (CFU/g) of microbes.
Dr. Mansour Samadpour, the CEO of IEH Laboratories, noted that leafy greens are not only raw but have a larger surface area than some other food items.
Total coliform numbers were also checked at the lab, the station reported. Samadpour said that ideally that number would be fewer than 200 CFU/g of total coliform. However, one leafy green sample had 80,000 CFU/g, while another had 13,000 CFU/g. Two other samples had fewer than 10 CFU/g.
One sample of a mix of raw carrots, broccoli and celery had 35,000 CFU/g, another broccoli, carrots and cucumber sample had 1,000 CFU/g, and one of tomatoes, carrots and banana peppers came in at 6,000 CFU/g, according to the lab tests. A sample of cucumbers, peppers and broccoli reportedly showed fewer than 10 CFU/g.
As for the mayonnaise-based salads, all samples tested were within the acceptable range for total coliforms, as were the cooked meat samples except for one, which contained 13,000 CFU/g, according to the TV report.
Samadpour told Food Safety News that high levels often happen with coliform tests and that people “read too much” into those particular results.
“They are supposed to be indicators of pathogens, but when you have already done your pathogen testing, there’s really no value in coliform testing,” he said, adding that coliform levels are an indicator of cleanliness and overall public health.
Samadpour also noted that a larger sample size is required in order to gain a clearer picture of pathogen contamination.
“To make sure you capture an event, you need to be over 300 samples,” he said.
WMBF video journalist Amy Lipman told Food Safety News that the story was prompted by a colleague who was walking through a local grocery store and thought maybe some items in the salad bar should be tested for safety.
She said she was assigned to do the piece because of an earlier story she did looking into whether sand from two local beaches contained fecal material (it did).
After hearing about the test results of the salad bar items, Lipman said some of her coworkers told her they wondered whether it’s a good idea to eat from salad bars. However, the results didn’t seem to faze her much.
“I’m already slightly germophobic as it is,” she noted, adding, “I overcook my food.”
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