Handle with care
While raw meats and eggs are the most common sources of illness-causing microbes, fresh fruits and vegetables can also carry the organisms that cause food poisoning.
Keep raw meats and fish away from other foods, especially those that won't be cooked.
Thaw frozen meats in the refrigerator, microwave oven, or under cold, running water-never on a counter.
Wash all produce before it's used, even if it looks clean. Produce that won't be peeled, such as strawberries or green onions, can be washed in plain water. If necessary, use a scrub brush to remove surface dirt. Wash lettuce leaves individually. Produce that will be peeled or eaten off the rind, such as oranges or cantaloupes, should be washed on the outside with soapy water and rinsed well.
Use paper towels and soapy hot water to clean utensils, counter surfaces, and cutting boards immediately after preparing raw meats and fish. If you use sponges, place them in the upper rack of the dishwasher. Wash your hands, faucets, and anything else you may have touched.
Don't undercook foods
Thorough cooking will kill most germs. To make sure foods get hot enough, check the internal temperature by inserting a food thermometer in the thickest part.
Meats: Cook beef and pork to at least 160 ° F, lamb to 145 °, and poultry to 180 ° for thigh meat and 170 ° for breasts. Ground beef, pork, veal, and lamb should be cooked to at least 160 °, and ground poultry to 165 °.
Seafood: Cook fish until it flakes with a fork. Simmer shrimp for three to five minutes or until the flesh turns pinkish and opaque. Steam clams and mussels for 5 to 10 minutes or until the shells open (if they don't, toss them out). Cook oysters until they're plump, for about five minutes. Don't eat raw oysters.
Eggs: Don't use homemade foods containing raw eggs, such as mayonnaise and Caesar-salad dressing. Commercial versions are okay, since manufacturers use heat-treated eggs. Use hard-boiled eggs within two to three days of cooking.
Marinate meats in the refrigerator. If you plan to use some of the marinade for a dip or basting sauce, make sure it has been boiled for at least 1 minute.
Keep vegetables or fruits intended for grilling separate from raw meats so no one will unwittingly munch on an uncooked, possibly contaminated piece of produce.
If you partially cook meat in advance to reduce grilling time, put it on the grill immediately afterward.
To transport hamburger patties, fresh meat, or poultry to a picnic site, place the food in a well-insulated cooler that keeps food at 40 ° or lower; store food in the cooler until it's time to start grilling.
Don't return cooked meats to the plates that held them when they were raw. Use a food thermometer to check temperatures of grilled meats.
Store foods as soon as possible
Serve picnic foods in a shaded area, keeping cold dishes on ice, hot foods on heating trays. Foods will stay cold longer if you divide them into small portions (for example, prepare several 9- by-12-inch trays, rather than one huge tray, of macaroni salad). Cold items should be kept below 40 °; hot foods should be 140° or higher.
Don't leave food sitting out for hours; instead, serve a few trays of food as guests arrive, so items will be quickly eaten. Replace empty trays with ones fresh from the refrigerator, oven, or grill.
Leftovers must cool rapidly when moved to the refrigerator or freezer, so microorganisms don't have time to multiply. To speed up cooling, divide large portions into smaller ones and store in shallow containers. Cut meat into portions less than three inches thick.