Normal kitchen utensils such as knives, graters, peelers and brushes can spread bacteria between different types of produce say scientists at University of Georgia in the US. Researchers showed that by using knives or graters to cut or grate a particular food and then using the same unwashed utensil to cut other produce, resulted in bacteria spreading from the first produce to the second.
The study also found that certain types of produce contaminated the instruments to different degrees. For instance, items like tomatoes tended to have a higher contamination of the knives than when strawberries were cut.
Scientists said that they did not yet know why there were differences between the different produce groups, but they did know that once a pathogen gets on the food, it is difficult to remove it. However, just knowing that utensils could lead to cross-contamination of produce should encourage consumers to wash their utensils between uses.