Microwave Cooking working principle Magic.ppt

Domestic Appliances

1. Microwave
Cooking

2. How it Works
Electromagnetic wave emitted by a magnetron tube
and set in motion by a fan or turn table
Some areas get more microwaves, resulting in
uneven cooking—rotating helps cook evenly
Microwaves are attracted to water, fat, and sugar
molecules causing them to vibrate and heat

3. Waves are emitted from an opening in the metal case.
Waves are then reflected off the sides and penetrate
food in the process.

4. Safety Features
Seal around door
Door Safety Switch/Short Circuit Safety
Switch (turns off when you open the door)
Do not attempt to use if the door does not seal
properly, is bent, or hinges or latches are
broken!

5. Utensils
Best to use glassware, china, or ceramic
dishes
Plastic and paper are good for reheating, but
not for prolonged cooking. They cannot
withstand high temperatures.
Make sure steam can escape or have room to
build up
Avoid wax coated materials, delicate glass and
anything containing metal

6. Is it safe to use?
Put an empty container in the microwave for 1
minute. Safe cookware should still be cool.
or
Measure 1 cup of water and put it in the dish in
question. Cook for 1 ½ -2 min.
If the dish stays cool, it is safe
to use in the mirowave.

7. Shapes and Arrangements
Foods cook around the outside edges first.
Position heavier/denser portions on the
outside.
Centers should be left empty, except when
cooking 1 item.
Use a glass or bowl to keep the center open

8. Position Items 1” Apart
2 items
5 or more items4 items
3 items

9. Shapes Etc. (cont.)
Rotate dish(es) ¼ turn once or twice during
cooking
Round shapes cook more evenly—corners have
more energy passed through them and may
overcook
High/tall foods close to the top also receive
more energy

10. Cooking / Reheating
•Defrost and various power levels indicate
the auto shutoffs at certain intervals
•Stir while cooking to prevent uneven
cooking
•Cooking times will differ for every
appliance as well as volume of food, size,
and cooking utensil

11. Cooking Tips
Covering while microwaving evokes similar
results from conventional cooking-steam is
retained to tenderize food and shorten
cooking time.
Shield some portions that are particularly
sensitive to overcooking.

12. Standing Time
Recipes allow for “standing time.”
This is the amount of time that it takes for
the food molecules to stop vibrating after
the microwave process ends.
Cooking continues during this period of
time, so it is factored into the recipe’s time
requirement.

13. Guidelines for Using Foil
Food quantity is muchgreater than
foil/skewers
Metal/foil is grounded along the bottom of
microwave

14. Browning
Foods cooked in a microwave often
do not have time to brown/crisp.
Additional ingredients can be used to
create a browning effect:

15. Browning Alternatives
Teriyaki/soy sauce
BBQ Sauce
Melted Butter
Worcestershire/steak sauce
Bread crumbs
Shredded Cheese
Brown Sugar
Nuts
Jellies, Preserves, and Glazes

16. Benefits
Time Savings-cook 3-4 times faster than
ovens
Energy Savings—Used up to 14% electricity
of conventional oven and less power for a
shorter period of time
No preheating
Auto-turn off
Quick and easy cleanup