Microwave Heating Guide

Microwave Heating Guide Image

Because plastics serve so many purposes in the kitchen, many consumers get confused about which ones are right for microwave use.  For example, can I reheat my spaghetti in a plastic takeout container?  What about the butter tub I washed out last week? 

When food is properly packaged and stored, plastics and the microwave work together to help you produce healthy, delicious meals in minutes.  To clear up the confusion, this guide offers tips on microwave cooking with plastics:

Follow the Directions

Most pre-packaged foods come with cooking instructions. Be sure to read and follow these directions carefully. Many packaging labels will tell you to either remove or cut slits in plastic wrap covering food trays. If there are no instructions, discard the packaging and use a plastic container that is labeled for use in the microwave.  A large variety of plastics are specially designed with flexibility and heat resistance for use with the microwave oven.

Size Matters

Cut food into uniform pieces and spread evenly around a microwaveable plastic dish.  During heating, rotate and turn pieces as needed.  If foods are different sizes, arrange them so thick parts face the perimeter.  Outer areas will cook faster than those in the center.    

That’s a Wrap

Plastic wrap helps trap heat and moisture so that food cooks evenly and thoroughly.  It also prevents messy splattering.  But plastic wrap can warp or even melt if used improperly and allowed to come into contact with extremely hot foods. Remember that it should cover the dish without touching the food.  

Not All Packaging Is Created Equal

Don’t use packaging containers for cooking unless the package tells you to.  Many plastic containers in which foods are sold, such as those used for butter and cottage cheese, are designed for cold storage and are not intended for cooking or reheating.  When in doubt, use a plastic container labeled for use in the microwave. 

Only Use Packaging Trays Once

Most plastic trays provided with prepackaged meals are intended for one-time use.

Divide and Conquer

Proper storage of leftovers and other previously cooked items is imperative for food safety.  Foods should be contained and stored in a refrigerator or freezer within two hours after cooking.  Divide leftovers into several shallow plastic dishes so they will cool to a safe temperature quickly.  Use refrigerated foods within the time period indicated on the cold storage chart.

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