How does a microwave oven
work?
The microwave oven contains a high-
frequency tube called a magnetron. It
converts electrical energy into
electromagnetic waves called
microwaves. These microwaves are
then distributed evenly throughout the
oven interior and reflected by its metal
walls, which allows the microwaves to
reach the food from all sides.
Distribution of the microwaves is
optimized by an activated turntable.
In order for microwaves to reach the
food, they must be able to penetrate
the cooking container being used.
Microwaves can penetrate porcelain,
glass, cardboard and plastics, but not
metal. Therefore, you should not use
containers which are either made of
metal or contain it in any form, such as
gold or silver trim. The metal reflects
the microwaves, which may cause
sparking to occur. The microwaves
cannot be absorbed.
The microwaves will pass through any
suitable cookware and find their way
directly into the food. All food contains
moisture molecules which, when
subjected to microwave energy, begin
to oscillate at a rate of 2.5 billion times
per second. The friction caused by
these vibrations creates heat, which
first starts developing around the
outside of the food and then slowly
penetrates it towards the center. The
more water a food contains, the faster it
is reheated or cooked.
Because the heat is produced directly
in the food:
–
The food can generally be cooked
using microwaves without adding
much liquid or cooking oil.
–
Defrosting, heating and cooking is
faster than when using a
conventional oven.
–
Nutrients, such as vitamins and
minerals, are generally retained.
–
The color, texture and taste of food
are hardly affected.
The production of microwaves stops
whenever the program is interrupted or
the microwave oven door is opened.
During operation, the closed and intact
door prevents microwaves from
escaping the appliance.
Principle of operation
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