27
Then they pass through the
cooking containers to be
a b s o r b e d by t h e w a te r
molecules in the food, all
foods contain water to a more
or lesser extent.
The microwaves cause the water molecules to vibrate
which causes FRICTION, i.e. 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 1½ - 2
inches(4-5cm) and as heat spreads through the food by
conduction, just as in a traditional oven, the food cooks
from the outside inwards.
MICROWAVING PRINCIPLES
Microwave energy has been used in this country to cook and reheat food since early experiments with RADAR in
World War ll. Microwaves are present in the atmosphere all the time, both naturally and manmade sources.
Manmade sources include radar, radio, television, telecommunication links and car phones.
CONVERSION CHARTS
HOW MICROWAVES COOK FOOD
In a microwave oven,
electricity is converted
into microwave by the
MAGNETRON.
The microwaves bounce
off the metal walls and
the metal door screen.
Oven Cavity
Magnetron
Waveguide
Turntable
REFLECTION
TRANSMISSION
ABSORPTION
Microwave
Water Molecule Absorption
Vibration
C O O K I N G I N S T R U C T I O N S
WEIGHT MEASURES
15 g
1
/
2
oz.
25 g
1 oz.
50 g
2 oz.
100 g
4 oz.
175 g
6 oz.
225 g
8 oz.
450 g
1 lb.
VOLUME MEASURES
30 ml
1 fl.oz.
100 ml
3 fl.oz.
150 ml
5 fl.oz. (
1
/
4
pt)
300 ml
10 fl.oz. (
1
/
2
pt)
600 ml
20 fl.oz. (1pt)
SPOON MEASURES
1.25 ml
1
/
4
tsp
2.5 ml
1
/
2
tsp
5 ml
1 tsp
15 ml
1 tbsp
FLUID MEASUREMENTS
1 Cup
= 8 fl.oz
= 240 ml
1 Pint
= 16 fl.oz. (UK 20 fl.oz.)
= 480 ml (UK 560 ml)
1 Quart
= 32 fl.oz. (UK 40 fl.oz.)
= 960 ml (UK 1120 ml)
1 Gallon
= 128 fl.oz. (UK 160 fl.oz.)
= 3840 ml (UK 4500 ml)
