FEATURE ARTICLE
Safer Salads
Contaminated fruits and vegetables are more common than ever. Why? And what can consumers do to protect themselves?
Jorge M. Fonseca, Sadhana Ravishankar
Tips for Consumers
Preventing the outbreak of foodborne illness is no small task. Fruits and vegetables can become contaminated at any point from the grower's field to the consumer's fork. Furthermore, disinfectants alone cannot ensure food safety, and they are particularly ineffective for produce that has punctures or wounds. Additional disinfection technologies are beginning to enter commercial use, but other than irradiation (which has significant disadvantages), no single sanitizing treatment eliminates all pathogens. In the light of such a bleak assessment, what's a consumer to do?
Fortunately, there are several steps one can take to avoid getting sick from tainted produce. The single best piece of advice is still to wash fruits and vegetables thoroughly before eating them—a practice that can result in a ten-fold reduction in surface contamination. Wash hands with soap before beginning, but just use lukewarm tapwater and a clean cloth or scrub brush on the food. It's usually best to wash no more than what will be eaten that day to limit microbial growth; however, washing, thoroughly drying (with a cloth or salad spinner) and promptly refrigerating produce is often fine and can sometimes prolong shelf life. Store produce in the refrigerator (except for those products that are not cold tolerant, such as bananas or pineapples). For leafy greens, ready-to-eat salads present no greater risk than lettuce or spinach washed in household kitchens.
Consumers have much more control over their exposure to foodborne pathogens when cooking at home. In preparing fruits or vegetables that will be eaten raw, cut away any damage and the area around the stem scar; these are often sites of microbial colonization. Also, remember that many instances of foodborne illness caused by fresh produce actually begin with cross-contamination from raw meat. Foodborne pathogens are much more likely to survive and thrive in uncooked meat than in fruits or vegetables, which explains why it is much safer to eat raw produce than to eat raw meat. Hands, surfaces and kitchen tools should be washed thoroughly with soap before and after preparing food, and it is prudent to wash hands frequently while cooking—most especially after handling meats or using the toilet.
Overall, it's important to put the risk of eating produce in a larger context. Fresh fruits and vegetables are no riskier than other fresh foods as sources of foodborne pathogens, and eating a salad is certainly safer than driving to work. Furthermore, many forms of produce confer remarkable health benefits on people who eat them. Given these benefits, avoiding fresh fruits and vegetables is probably riskier than enjoying them—even if you still eat unwashed fruit with grubby fingers.
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