9
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 11⁄2-2 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 more or
lesser extent.
How Microwaves cook food
13 Amp fused socket
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.
Boiled eggs
Do not boil eggs in your microwave. Raw eggs boiled in their shells can explode and cause serious
injury
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 11).
Important notes
