Kitchen utensils can spread bacteria

Bacteria from produce can latch onto kitchen knives and spread them around, according to a study by the University of Georgia.

Unfortunately, many consumers are unaware that utensils and other surfaces at home can contribute to the spread of bacteria, said the study’s lead author Marilyn Erickson, an associate professor in the College of Agricultural and Environmental Sciences’ department of food science and technology.

“Just knowing that utensils may lead to cross-contamination is important,” Erickson said. “With that knowledge, consumers are then more likely to make sure they wash them in between uses.”

This study, published in Food Microbiology, is similar in that it considers the influence that knives and graters have on the transfer of pathogenic bacteria to and from produce items. She urges consumers to realize that these germs can spread in their kitchens as well.

In her recent study, Erickson contaminated many types of fruits and vegetables in her lab–adding certain pathogens that often can be found on these foods, such as salmonella and E. coli.

Using a knife, Erickson would cut into things like tomatoes or cantaloupe and other types of produce to see how easily the bacteria could spread when the knife was continuously used without being cleaned. Because they “were looking at what would be the worst-case scenario,” she said, Erickson and study co-authors did not wash between cutting these different produce items.

Researchers also grated produce, like carrots, to see how easily the pathogens spread to graters. They found that both knives and graters can cause additional cross-contamination in the kitchen and that the pathogens were spread from produce to produce if they hadn’t washed the utensils.

“A lot of the broken up material and particles from the contaminated produce remained on the graters,” said Erickson, who conducts her research at the UGA Center for Food Safety in Griffin. “Then if you were to shred another carrot or something else immediately after that, it gets contaminated, too.”

The study also found that certain fruits and vegetables spread pathogens to knives to different degrees.

“For items like tomatoes, we tended to have a higher contamination of the knives than when we cut strawberries,” Erickson said. “We don’t have a specific answer as to why there are differences between the different produce groups. But we do know that once a pathogen gets on the food, it’s difficult to remove.”

Knives and graters aren’t the only utensils in the kitchen consumers should be worried about. Erickson has also helped study the role brushes and peelers have on the transfer of dangerous kitchen bacteria.

Category: Health alert, Top Story