The theory of microwave cooking
When the microwave oven is plugged in. the ordinary electrical current is converted to microwaves by a tube called a magnetron. The microwaves are of very short wave length and high frequency The waves are then channelled into the cavity of the oven. Distribution of microwaves is evenly done by a stirring fan installed in the oven. The oven walls will reflect the microwave energy directly to the food, causing its molecules to vibrate at an incredibly high speed. These vibrations generate the heat that cooks the food, without heating the oven or cooking container. although a container may sometimes be warmed subsequently by the conduction of heat from the food cooked in it.
Once the door of the oven is opened, during or after cooking, the magnetron producing microwaves automatically switches off. and cooking by microwave
energy stops instantly. Microwaves cook in three ways:
1.Microwaves are reflected to the foods by the metal walls of the oven. Never use metal utensils or utensils with metal trims, because they reflect microwaves away from the food.
2.Microwaves are transmitted through certain substances such as paper. plastic, glass and ceramic without producing heat. Cookware made of these materials are sometimes suitable for use in a microwave oven. For further details. see "Cooking Utensil"
3.Microwaves are attracted to the
liquid. sugar, fat or moisture content in foods, causing them to vibrate at an incredibly high speed. As the vibrating molecules rub against each other, this causes friction. thereby creating heat within food.
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