8
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 -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 more or lesser extent.
Important notes
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 in
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 9.)
Boiled Eggs
Do not boil eggs in your microwave. Raw
eggs boiled in their shells can explode and
cause serious injury.
13 Amp fused socket
1
/
2
