Panasonic NN-CD987W - Manual (Page 7)

Bef
ore
Operation
-5-
General Instructions
Microwaves are a form of high frequency radio
waves similar to those used by a radio, including
AM, FM and CB .
Electricity is converted into microwave energy by the
magnetron tube (which is the heart of the microwave
oven) .
From the magnetron tube, microwave energy is
transmitted to the oven cavity . The microwaves are
converted to heat in the food . The microwaves enter
from the outside of the food and travel through the
food . Continued cooking to the centre occurs by
conduction .
Although pacemakers used to be affected by
microwaves (as well as by other radio waves), they
are now shielded and are not bothered by these
interferences . This allows people with pacemakers to
sit calmly by their radio or television and cook with
microwave ovens .
When the microwaves come in contact with a
substance, any one or a combination of three things
may occur . They can be:
 . REFLECTED
2 . TRANSMITTED
3 . ABSORBED
Reflection
Metal substances REFLECT microwave energy
because there is no absorption and there is no
heating . This is why the oven interior is either
stainless steel or paint-coated steel . This ensures
that the microwaves are kept inside the cavity and
evenly distributed throughout the food with the help
of the turntable .
Transmission
Such substances as paper, glass and plastic
TRANSMIT microwave energy and do not become
hot except from food . Because these substances
do not reflect or absorb microwave energy, they are
ideal materials for microwave cooking containers .
Absorption
Food contains moisture and will ABSORB
microwave energy, which causes the moisture
molecules within the food to vibrate at an incredible
rate (2,450,000,000 times per second) . Friction,
created by vibration, produces heat energy which is
conducted throughout the food .
6 . COOKING TIMES given in the cookbook
section are APPROXIMATE. Factors that may
affect cooking time are preferred degree of
cooking, moisture content, starting temperature,
altitude, volume, size, shape of food and utensils
used . As you become familiar with the oven, you
will be able to adjust for these factors .
7 . It is better to UNDERCOOK RATHER THAN
OVERCOOK foods. If food is undercooked, it
can always be returned to the oven for further
cooking . If food is overcooked, nothing can be
done . Always start with minimum cooking times
recommended .
8 . Extreme care should be taken when cooking
popcorn . Cook for minimum time as recommended
by manufacturer . Use the directions suitable for
the wattage of your oven . NEVER leave oven
unattended when popping popcorn .
9 . Take care when heating food in foil trays . Trays
should be no deeper than 2 cm and should not
touch the sides of the oven walls . If you are
unsure of the heating time, do not leave the oven
unattended .
Microwaves and How They Work