Microwave ovens can be a very useful appliance for the family on the run. But because microwaves can cook unevenly and leave cold spots where bacteria can survive, precautions must be taken.

Use the following safe microwaving tips to keep your food safe and prevent foodborne illness:

Food items should be arranged evenly in a covered dish with some liquid added if needed. Cover the dish with plastic wrap or a lid and loosen the plastic wrap or vent the lid to let steam escape. The steam helps to kill harmful bacteria and ensure uniform cooking. Using cooking bags are another way to ensure safe, even heating.

When cooking large cuts of meat in the microwave, be sure not to cook them on high power (100 percent). Cooking large cuts of meat on medium power (50 percent) for a longer period of time allows the meat to cook all the way through without overcooking the outside.

Stir dishes halfway through microwaving time to eliminate cold spots and ensure more even heating.

When partially cooking food in the microwave that will be cooked the rest of the way on the grill or in a conventional oven, be sure to move the food from the microwave to the other heat source immediately. Never partially cook a food in the microwave and store it for later use.

Use a food thermometer to make sure food that has been cooked in the microwave has reached a safe internal temperature. The thermometer should always be placed in the thickest area of meat or poultry, not near fat or bone. In whole poultry, the thermometer should be placed in the innermost part of the thigh. Cooking times may vary from microwave to microwave due to different power and efficiency. Red meat should reach 160 degrees, whole poultry should reach 180 degrees and egg casseroles need to be cooked to 160 degrees. Be sure to take the temperature of microwave cooked foods in several different spots to ensure that the food has cooked evenly. Fish is done when it flakes with a fork. Standing time completes the cooking process of microwave cooked food. Always allow standing time before checking the internal temperature of the food.

Cooking whole, stuffed poultry in the microwave is not recommended because the stuffing might not reach a high enough temperature to kill harmful bacteria.

Defrosting in the microwave:

When defrosting food in the microwave, remove the food from packaging. Foam trays and plastic wraps are not heat stable and could break down during cooking causing harmful chemicals to leach in to the food.

Immediately cook meat, poultry, egg casseroles and fish that have been defrosted in a microwave oven. Parts of the frozen food may have begun to cook during the defrosting process and partially cooked food should never be held for later use.

When reheating foods in the microwave, cover them with a lid or microwave-safe plastic wrap. Covering the foods helps to hold in the moisture and provides safe, even heating.

Ready-to-eat foods like hot dogs, luncheon meats and leftovers should be heated until steaming hot.

Allow for standing time for foods that have been reheated in the microwave oven. After the food has been allowed to stand, use a clean food thermometer to check that the leftovers have been heated to 165 degrees.

Only use cookware that is labeled safe for microwave use.

Plastic containers such as margarine tubs, take-out containers and other one-time-use containers should not be used in microwaves because of the risk of the container melting or warping and leaching dangerous chemicals into the food.

Products that are safe to use in the microwave include microwaveable plastic wraps, wax paper, cooking bags, parchment paper and white microwave-safe paper towels. Plastic wraps should not touch foods during microwaving.

Products that are NOT safe to use in the microwave include thin plastic storage bags, brown paper or grocery bags, newspapers or aluminum foil.

Debbie Wilburn is county extension agent in family and consumer science with the Hall County Extension Service. Contact: 770-535-8290.