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 choc ID: 342084
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MicrowavesSlide2
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!Slide3
Diagram of a MicrowaveSlide4
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.
motion
friction
heatingSlide5
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.Slide6
Microwaves
Microwaves are attracted to foods that are high in:
water
fat
sugarSlide7
Microwave-able Containers
PaperPlasticGlass
Microwaveable DishesSlide8
Non-Microwave-able Containers
Metal
Dishes with gold or silver on it.Slide9
Acceptable coverings for microwave dishes:
Paper towel – to absorb moisture, spatters, and spills.Wax paper – holds in some of the moisturePlastic wrap – hold in moistureSlide10
Techniques for Microwaving
Stirring: To pull heated part of the food to the centerTurning over: To microwave all sidesRotating: Makes cooking evenPricking: To keep foods from exploding
Standing Time: To allow foods to complete its cooking by placing on the counter.Slide11
Cooking Time
These will increase the cooking time and standing time.The volume of the food Example: Small potatoes versus large potatoesThe quantity or number of food
Round containers will cook more evenly than square containers.Slide12
Microwave Safety
To prevent burning yourself from microwave cooking, remember:Foods can create hot containersItems can explode (eggs, potatoes). Pierce them with a fork.Lifting the cover or plastic from the food can cause a burn.
Hot steam escaping can cause a burnSlide13
What foods should not be microwaved?