In the microwave oven, food is cooked,
reheated or defrosted quickly.
How does the microwave oven func-
tion?
In a microwave oven there is a high-fre-
quency tube called a magnetron. This
converts electrical energy into micro-
waves. These microwaves are distrib-
uted evenly throughout the oven interior
and rebound off the metal sides of the
oven interior to reach the food from all
sides. Microwave distribution is im-
proved with the turntable engaged.
In order for microwaves to reach the
food, they must be able to penetrate
the cooking utensil being used. Micro-
waves can penetrate porcelain, glass,
cardboard and plastics but not metal.
Do not, therefore, use utensils made of
metal, or which contain metal, for exam-
ple in the form of gold or silver trim. The
metal reflects the microwaves and this
could lead to the creation of sparks.
The microwaves cannot be absorbed.
Microwaves pass through a suitable
container and find their way directly into
the food. All food contains moisture
molecules which, when subjected to
microwave energy, start to oscillate 2.5
thousand million times a second. The
friction caused by this vibration creates
heat, which first starts developing
around the outside of the food and then
slowly penetrates towards the centre.
The moisture, fat and sugar content of
food will affect the speed at which it is
cooked.
As heat is produced directly in the
food,
– food can generally be cooked with-
out adding much liquid or cooking
oil.
– cooking, re-heating and defrosting in
a microwave oven is quicker than us-
ing conventional methods.
– nutrients, such as vitamins and min-
erals, are generally retained.
– colour, texture and taste of food are
not impaired.
Microwaves stop being produced as
soon as the cooking process is inter-
rupted or the appliance door is opened.
When the appliance is in operation, the
closed, sealed door prevents micro-
waves escaping from the appliance.
How the microwave oven functions
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