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The microwaves used for cooking are electro-magnetic waves. They exist in our
environment as do radioelectric waves, light, and infrared rays.
Their frequency is 2,450 MHz.
Their characteristics :
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They are reflected by metals.
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They pass through all other materials.
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They are absorbed by water, sugar and fat molecules.
When food is exposed to microwaves there follows a vibration of the molecules at a speed
of 2 billion 450 million times a second, which in turn produces heat.
The depth of penetration of the waves into food is about 2.5 cm. If the food is thicker the
centre is cooked by normal conduction of heat. It is worth noting that the microwaves pro-
duce a simple heat reaction inside food and are not at all harmful to your health.
How microwaves work
