1. How does a microwave work???
Microwaves
How does a microwave work???

2. History of Microwaves
In 1945, Dr. Perry Spencer, a scientist, was working in a lab when he felt some heat on his hand.
The heat was coming from microwaves. These were being emitted from a nearby vacuum tube. Dr. Spencer was curious and place a chocolate bar near the tube.
Within seconds, the chocolate melted. That sticky mess was the beginning of a brilliant idea – the microwave!

3. Diagram of a Microwave
Handbook p. 13

4. How Does a Microwave Work?
The microwave oven generates electromagnetic waves (called microwaves) which makes water move. This motion leads to friction, and friction leads to heating.
friction
heating
motion

5. How Does a Microwave Work?
This heat starts on the outside of the food and moves in.
The denser the food the longer it will take to cook.
Water will heat faster than a burrito, because a burrito is more dense than water.

6. Microwaves Microwaves are attracted to foods that are high in: sugar
fat
water

7. Microwave-able Containers
Paper
Plastic
Glass
Microwaveable Dishes
Handbook p. 6

8. Non-Microwave-able Containers
Metal
Dishes with gold or silver on it.
If you’re unsure, check the label on the dishware.

9. Acceptable coverings for microwave dishes:
Paper towel – to absorb moisture, spatters, and spills.
Wax paper – holds in some of the moisture
Plastic wrap – hold in moisture

10. Techniques for Microwaving
Stirring: To pull heated part of the food to the center
Turning over: To microwave all sides
Rotating: Makes cooking even
Pricking: To keep foods from exploding
Standing Time: To allow foods to complete its cooking by placing on the counter.

11. Cooking Time These will increase the cooking time and standing time:
The volume of the food
Example: Small potatoes versus large potatoes
The quantity or number of food

12. Microwave Safety
To prevent burning yourself from microwave cooking, remember:
Foods can create hot containers…Use Pot Holders
Items with an unbroken outer “skin” can explode. Pierce them with a fork.
Items with an unbroken outer “skin” potatoes, hot dogs, apples, sausages, chicken livers, etc.
Lifting the cover or plastic from the food can cause a burn.
Hot steam escaping can cause a burn

13. Cooking Controls Time Features Convenience Features 1 2 3 4 5 6
Time Cook
Amount of cooking time
Starts Immediately (1,2,3,4)
Starts Immediately (1 or 2)
Food Type 1-4
Time Defrost
Amount of defrost time
Popcorn
Beverage
Reheat
Power Level
Add 30 Sec
Power Level
1-10
Starts Immediately
Cook
Food Type (1-6)
Express Cook
Starts Immediately
Handbook p 1 2 3
Auto Defrost
Food type & Weight 4 5 6
Kitchen Timer

14. Cooking Controls Microwave for any time up to 99 minutes.
Time Cook
Time Defrost
Microwave for any time up to 99 minutes.
Press time cook
Enter cooking time
Change power level if needed
Press start
Defrost for a selected length of time.
Press Time Defrost
Enter defrosting time
Press start
Handbook p. 20

15. Cooking Controls Power Level Press Time Cook OR Time Defrost
Enter cooking or defrosting time
Press Power Level
Select Desired power level 1-10
Press start
Each power level gives you microwave energy a certain % of the time.
Power level 7 = 70%
Power level 10 = 100%
Lower settings cook more evenly & need less stirring or rotating.
Higher settings cook faster

16. What things should not be microwaved?
Handbook p.4

17. Potato Lab How to cook a potato in the microwave
How to make Cheese Sauce on the stove top

18. Microwave Potato Lab
 Baked Potatoes- ½ potato per person. You will share with a person in your group!
Prick a well-scrubbed potato several times with fork tines.
Microwave on HIGH for 6 to 8 minutes, using 100 percent power.
Turn the potato over and rearrange. Cook for additional 6 to 8 minutes until done. Wrap in foil.
Let stand 5 to 8 minutes to finish cooking.
Broccoli 
Wash, cut and chop broccoli into bite-size pieces.
Put in a glass pie plate with saran wrap.
Add 1-2 tablespoons of water.
Cover with saran wrap.
Cook on HIGH for 3-5 minutes or until tender crisp and done. Place in a small bowl. Let stand, keep covered, for 5 minutes.
Drain any excess water and mix with the cheese sauce.

19. Microwave Potato Lab Cheese Sauce 2 tbs. butter
2 tbs. plus 1 tsp. flour
Dash pepper
1 ¼ cup milk
1 ¼ cup grated cheese
In a pot, melt butter
Gradually, stir in flour and pepper. Mix with a wisk
Continue until the mixture is smooth.
Add milk all at once. Stir until combined.
Cook, uncovered, on HIGH for 3 to 5 minutes or until thickened and bubbly; stirring until the sauce starts to thicken.
Stir every 30 seconds.
Add 1 ¼ cup grated cheese and stir until the cheese is melted.
Then pour over the cooked broccoli and serve on top of the potato.

20. 5 Easy Microwave Desserts you need to Try!
Video

21. Are microwaves Dangers?
Video Clip