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Microwaves used for cooking are
electromagnetic waves. They are
commonly found in our environment in
the form of radio waves, light and infra-
red rays.
Their frequency is in the 2450MHz range.
Their behaviour:
· They are reflected by metals.
• They pass through any other
material.
• They are absorbed by water, fat
and sugar molecules.
When food is exposed to microwaves, its
molecules begin moving rapidly, causing
it to heat up.
The depth of penetration of the waves
into the food is about 2.5 cm. If the food
is thicker, cooking at its centre occurs by
conduction just like traditional cooking.
In essence, microwaves are simply
causing a thermal change inside the food
and are therefore not harmful to health.
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COOKING
OPERATING PRINCIPLE
