Mixed lettuces, carrots, cabbage—boxed and bagged salad ingredients are a staple of many people’s shopping lists, but one of these prepackaged vegetables may have been the source of an outbreak of food poisoning this summer.Cyclospora is a parasite that has been confirmed to have affected 372 people in 15 states since June. Health officials in Iowa and Nebraska have determined that mixed bagged salad containing iceberg and romaine lettuces, plus carrots and red cabbage, was the culprit. The U.S. Food and Drug Administration announced that the tainted salad mix served at restaurants in both states came from Taylor Farms in Mexico.Bonnie Taub-Dix, R.D., author of “Read It Before You Eat It” and nutrition expert in New York, says there’s no reason for people to stop eating salads or eschew bagged vegetables. “Don’t think all lettuce is to be avoided,” she advises. She does, however, have a few tips on making sure your produce is clean and fresh:Check the date. “It sounds silly, but so many people associate bagged or boxed veggies with items they find on a shelf that last for way longer,” says Taub-Dix. “Even though it’s organic and looks attractive, that doesn’t mean it’s very fresh. Always make sure your produce is current.”Refrigerate ASAP. “Don’t go food shopping and then make five other stops while the food is in the hot car,” she advises. “Make the supermarket your last errand of the day so you can go home afterwards and refrigerate things.”Wash—and watch. It can’t hurt to rinse salad well—even the prewashed kind. “Washing all of your veggies is a good habit,” says Taub-Dix. “Even if it says it’s been prewashed, why not give it another rinse and dry, just to be safe?” That said, even careful washing of these foods isn’t enough to eliminate the parasite that caused the infection, according to the Mayo Clinic. Your best bet: To keep track of what foods have been linked to recent outbreaks of cyclospora, try periodically checking the food recalls section of the Food and Drug Administration’s website.Make your own. If you’re still wary of bagged salad mixes, buy the individual ingredients—dark lettuces, cabbage, carrots—and mix them yourself. That way you’ll control the individual washing processes, and—bonus!—you’ll have more salad overall than if you’d bought a mix.