11
Microwaving principles
Magnetron
Oven Cavity
Turntable
Waveguide
Microwave energy has been used in this
country to cook and reheat food since ear
O
y
e
[
periments with radar in
:
or
O
d
:
ar
,,
.
Microwaves are present in the
atmosphere a
OO
the time, both natura
OO
y
and from manmade sources. Manmade
sources inc
O
ude radar, radio, te
O
evision,
te
O
ecommunication
O
inks and mobi
O
e
phones.
,
n a microwave oven, e
O
ectricity is converted
into microwaves by the
MAGNETRON
.
How Microwaves cook food
The microwaves cause the water mo
O
ecu
O
es
to vibrate which causes
FRICTION
, i.e.
HEAT
. This heat then cooks the food.
Microwaves are a
O
so attracted to fat and
sugar partic
O
es, and foods high in these wi
OO
cook more
T
uick
O
y. Microwaves can on
O
y
penetrate to a depth of
5 cm
1
ô
²
inches
and as heat spreads through the
food by conduction,
M
ust as in a traditiona
O
oven, the food cooks from the outside
inwards.
Important notes
The dish used to cook or reheat the food
wi
OO
get warm during cooking, as the
heat conducts from the food. Even in
microwaving, oven g
O
oves are re
T
uired
MICROWAVES CANNOT PASS
THROUGH META
/
AND THERE FORE
META
/
COOKING UTEN SI
/
S CAN
NEVER BE USED IN A MICROWAVE,
FOR COOKING ON MICROWAVE ON
/
Y.
Re
Å
ection
The microwaves bounce off the meta
O
wa
OO
s
and the meta
O
door screen.
Transmission
Then they pass through the cooking
containers to be absorbed by the water
mo
O
ecu
O
es in the food, a
OO
foods contain
water to a more or
O
esser e
[
tent.
Foods Not Suitable for Cooking by
Microwave Only
Yorkshire Puddings and
6
ouf
Á
es. This is
because these foods re
O
y on dry e
[
terna
O
heat to cook correct
O
y, do not attempt to
cook by micro wave.
Foods that re
T
uire deep fat frying cannot be
cooked either.
Standing Time
:
hen a microwave oven is switched off,
the food wi
OO
continue to cook by conduction
²
1
OT
%
Y M
,&
RO
:$9
E E
1
ER
*
Y.
+
ence
6
T
$1',1*
T
,
ME is very important in
microwaving, particu
O
ar
O
y for dense foods
i.e. meat, cakes and reheated mea
O
s
refer
to page 1
.
Boiled Eggs
'
o not boi
O
eggs in your microwave. Raw
eggs boi
O
ed in their she
OO
s can e
[
p
O
ode and
cause serious in
M
ury.
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2012-8-17 13:38:17
2012-8-17 13:38:17
