10
Microwave energy has been used in this country to cook and
reheat food since early experiments with radar in World War II.
Microwaves are present in the atmosphere all the time, both
naturally and from manmade sources.
Manmade sources include radar, radio, television,
telecommunication links and car phones.
Microwaving Principles
The microwaves cause the water molecules to
vibrate which causes FRICTION, ie. HEAT.
This heat then cooks the food. Microwaves are
also attracted to fat and sugar particles, and
foods high in these will cook more quickly.
Microwaves can only penetrate to a depth of
1
1
⁄2-2 inches (4-5 cm) and as heat spreads
through the food by conduction, just as in a
traditional oven, the food cooks from the
outside inwards.
In a microwave oven,
electricity is converted
into microwaves by the
MAGNETRON.
REFLECTION
The microwaves bounce
off the metal walls
and the metal door screen.
TRANSMISSION
Then they pass through
the cooking containers to
be absorbed by the water
molecules in the food, all
foods contain water to a
greater or lesser extent.
How Microwaves cook food
The dish used to cook or
reheat the food will get
warm during cooking, as the
heat conducts from the
food. Even when micro -
waving, oven gloves are
required!
MICROWAVES CANNOT
PASS THROUGH METAL
AND THERE FORE METAL
COOKING UTEN SILS CAN
NEVER BE USED IN A
MICROWAVE, FOR
COOKING ON
MICROWAVE ONLY
Foods Not Suitable for
Cooking by Microwave
Only
Yorkshire Puddings,
Souffles, Double Crust
Pastry Pies.
This is because these foods
rely on dry external heat to
cook correctly, do not
attempt to cook by micro -
wave.
Foods that require deep fat
frying cannot be cooked
either.
STANDING TIME
When a microwave oven is
switched off, the food will
continue to cook by
conduction – NOT BY
MICROWAVE ENERGY.
Hence STANDING TIME is
very important in
microwaving, particularly for
dense foods i.e. meat,
cakes and reheated meals
(Refer to page 12).
Boiled Eggs
Do not boil eggs in your
microwave. Raw eggs
boiled in their shells can
explode and cause serious
injury
Important Notes
13 Amp fused socket
Magnetron
Wave Guide
Turntable
Oven cavity
