Microwave defrosting is the act of thawing frozen foods in the microwave oven without cooking them. It must be done at lower power to keep from cooking the food on the outside while it remains frozen or raw inside. Thawing food at room temperature for more than an hour or two can cause dangerous bacteria to grow in it that will make you sick when you eat it.

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Thawing frozen food, especially meat, poultry, fish and egg products, should be done with care.

Defrost

Many microwaves come with a defrost button. When used, this button automatically sets the oven's power lower, anywhere from 30 to 50 percent of its full power. Such a low setting allows the heat waves to penetrate the center of the food before cooking the outer layers. Most of these buttons require you to know the approximate weight of the food you are thawing.

No Defrost

If your unit is not equipped with a defrost button, simply set the unit to cook at 30 to 50 percent of its full power. Many meats require eight to 10 minutes per pound being thawed, so base your time on the weight of your item. For instance, if you are thawing 1 pound of chicken, set it on eight minutes, but stop it frequently to turn and flip the meat to be certain it gets thawed through. Do not leave thawing meat unattended.

After Defrosting

Do not leave thawed raw food in the microwave but instead cook it immediately. It can be cooked thoroughly in the microwave or transferred to a conventional oven. You may freeze the food again after it has been cooked completely, but never refreeze defrosted food without cooking. Always remove all packaging from food before placing it into the microwave or oven.

Other Methods

To safely defrost food without a microwave, place frozen food in your refrigerator until it is thawed. To more quickly thaw food, submerge the package in cold water for a few minutes. It is important that the outer layer of the food not get above 40 degrees F, as this is the temperature at which bacteria can begin to grow. Any time you are thawing food, especially food containing raw meat, keep a close eye on it, and cook it as soon as it is thawed. Frozen foods have a long shelf life, but refrigerated foods do not.