Nutrition Column – Consider Food Safety When Microwaving Food

Microwave ovens can play an important role at mealtime for individuals and families on the go. Special care is needed, however, to make sure foods prepared or reheated in the microwave oven are safe to eat. Here are some tips to help ensure the safety of microwaved foods.

Make sure containers and wraps are microwave-safe

  • Only use cookware that has been specially manufactured for use in the microwave oven. Glass, glass ceramic containers and all plastics should be labeled for microwave use.
  • Storage containers such as margarine tubs, whipped topping bowls and cheese containers should not be used in microwave ovens. These containers can warp or melt, possibly causing harmful chemicals to migrate into the food.
  • Wax paper, oven cooking bags, parchment paper and plastic wrap or paper towels that are specifically designed for use in microwave ovens should be safe to use. However, avoid letting plastic wrap touch foods during microwaving.
  • Never use thin plastic storage bags, plastic grocery bags or plastic trash bags in the microwave oven. These generally are not made of food-grade plastic and may contain chemicals that could leach into the food.
  • Don’t use aluminum foil, brown paper bags or newspapers in the microwave oven. Microwaves will not pass through aluminum foil and its use could cause arcing and fire in your microwave. Brown paper bags and newspapers also could cause fires and might allow migration of unwanted chemicals into microwaved foods.

Other food safety tips when microwaving

  • When defrosting in the microwave, its best to remove food from its packaging. Foam trays and plastic wraps are not heat-stable at high temperatures. Melting or warping may cause harmful chemicals to migrate into food.
  • Cook meat, poultry, egg casseroles and fish immediately after defrosting in the microwave. Some areas of the frozen food may begin to cook during the defrosting time. Do not hold partially-cooked food to use later.
  • If only partially cooking food in the microwave to finish cooking on the grill or in a conventional oven, be sure to transfer the microwaved food to the other heat source immediately. Never partially cook food and store for later use.
  • Use the oven’s temperature probe, or a food thermometer inserted into the product after removing from the oven, to verify that the food has reached a safe temperature.
  • When reheating ready-to-eat, take-out, precooked foods and leftovers in the microwave, make sure they are heated until steaming hot. Cover foods with a lid or microwave-safe plastic wrap to hold in moisture and provide safe, even heating. After removing reheated foods from the microwave oven, use a clean food thermometer to check that food has reached 165 degrees F.

For additional information on safe microwave cooking, call USDA’s Meat and Poultry Hotline at 1 (800) 535-4555.