Microwave ovens are convenient and safe when used properly, but they can heat food unevenly. Uneven heating can create “cold spots” where harmful bacteria may survive. Following safe microwave cooking practices helps reduce the risk of foodborne illness.
Defrosting Food
- Remove food from store packaging before defrosting in the microwave unless the packaging is labeled microwave-safe. Foam trays and plastic wraps used in grocery packaging may melt or warp when heated and are not designed for microwave cooking.
- Cook meat and poultry immediately after microwave thawing. During microwave defrosting, parts of the food may begin to cook while other areas remain frozen. If partially cooked food is left at room temperature, bacteria can multiply.
- Do not leave thawed food out of refrigeration for more than 2 hours (or 1 hour if the temperature is above 90°F outside).
Utensils Safe for Microwave Cooking
If you are not sure whether pottery or dinnerware is microwave-safe, place the empty dish in the microwave alongside a cup of water in a glass measuring cup. Microwave on high for 1 minute. If the dish remains cool, it is safe to microwave. If the dish becomes warm or hot, it should not be used in the microwave.
Safe containers include:
- Glass or glass-ceramic cookware
- Microwave-safe plastic containers labeled for microwave use
- Ceramic dishes without metallic trim
- Wax paper, parchment paper, microwave cooking bags, or microwave-safe paper towels
Containers that should not be used include:
- Metal pans or aluminum foil containers (unless specifically approved by the microwave manufacturer)
- Brown paper bags, newspapers, or plastic grocery bags
- Thin plastic storage bags
- Containers such as margarine tubs, yogurt containers, or whipped topping bowls that are not labeled microwave-safe
These containers may melt, warp, or allow chemicals to migrate into food when heated.
Microwave Cooking Basics
- Arrange food evenly in a microwave-safe dish. Adding a small amount of liquid and covering the dish loosely helps produce steam and improves even heating.
- Stir foods or rotate dishes during cooking. Turn large food items over midway through cooking.
- Pierce foods such as hot dogs, sausages, or baking potatoes before microwaving to prevent bursting.
- Use potholders when removing dishes from the microwave and uncover foods carefully to avoid burns from escaping steam.
Safe Reheating Practices
- Cover foods when reheating in the microwave to hold moisture and promote even heating.
- Stir or rotate foods midway through heating to reduce cold spots.
- Allow food to stand for several minutes after microwaving. Standing time allows heat to distribute evenly and finish cooking.
- Always use a food thermometer to verify internal temperatures.
Special Note for Baby Food and Formula
- Microwaving baby food or infant formula can create uneven hot spots that may burn a baby’s mouth.
- If microwaving, stir food thoroughly, shake bottles well and test the temperature before feeding.
Foods That Should Not Be Microwaved
- Do not microwave whole stuffed poultry. The stuffing inside may not reach a safe temperature before the outside meat overcooks.
- Avoid partially cooking raw meat in the microwave and finishing it later unless it is immediately transferred to another cooking method such as grilling or baking.
Cooking Meat, Poultry, and Eggs in the Microwave
Use a food thermometer and check the temperature in several places because microwave ovens heat unevenly.
Safe Minimum Internal Temperatures
| Food | Safe Minimum Temperature |
|---|---|
| Poultry (chicken, turkey, duck) | 165°F |
| Ground meats (beef, pork, lamb) | 160°F |
| Whole cuts of beef, pork, lamb, or veal | 145°F + 3-minute rest |
| Fish and seafood | 145°F |
| Egg dishes | 160°F |
| Leftovers and casseroles | 165°F |
Cooking times may vary depending on the microwave oven’s power level. Large pieces of meat should be cooked on medium power for longer periods to allow heat to penetrate evenly.
References
- U.S. Department of Agriculture, Food Safety and Inspection Service. (n.d.). Cooking and reheating in microwave ovens. Retrieved March 10, 2026, from https://www.fsis.usda.gov
- U.S. Department of Agriculture, Food Safety and Inspection Service. (n.d.). Safe minimum internal temperature chart. Retrieved March 10, 2026, from https://www.fsis.usda.gov
- U.S. Food and Drug Administration. (n.d.). Microwave oven safety. Retrieved March 10, 2026, from https://www.fda.gov
- Centers for Disease Control and Prevention. (n.d.). Food safety. Retrieved March 10, 2026, from https://www.cdc.gov/foodsafety
Document last updated on 6/26 by Myeesha Lance, MPH.
Originally published 02/99
