Ppt. microwaves

Microwaves

In 1945, Dr. Perry Spencer In 1945, Dr. Perry Spencer was working in his lab was working in his lab when he felt heat when he felt heat coming from a nearby coming from a nearby vacuum tube emitting vacuum tube emitting microwaves. He placed microwaves. He placed a chocolate bar near the a chocolate bar near the warm tube and watched warm tube and watched it melt which was the it melt which was the beginning of the modern beginning of the modern day microwave! day microwave!

A MAGNETRON TUBE emits electromagnetic waves evenly throughout the microwave causing MOTION of water molecules in food, creating FRICTION, resulting in HEAT -cooking the food.

Motion Friction HeatThis heat starts on the outside of the food & moves in. The more dense the food, the longer it will take to cook. EXAMPLE = A baked potato vs. herbal tea

Ingredients microwaves are attracted to are:

1. Fat

2. Sugar

3. Water

Acceptable Microwave Cookware:

- Glass- Glass

- Paper or Plastic- Paper or Plastic

- Microwave Cookware- Microwave Cookware

Unacceptable Microwave Cookware:

Metal pans:

DANGEROUSLY hot and reflective heat

Decorative China: pieces with gold or silver plating on it = TOO HOT!

Acceptable Coverings:Paper Towels: Absorbs moisture, spatters, and spills NOT RECYCLED PAPER!

Waxed or Parchment Paper: Prevents splatter messes Holds in some of the moisture

Plastic Wrap: Holds in moistures; BE CAREFUL!

Cookware Lid:

Prevents splatters and

retains moisture.

Microwave Techniques:Stirring: To distribute heat of food evenly.Turning Over: To microwave food all sides.Covering:

A: Retains nutrients B. Holds in moisture C. Speeds up cooking

Rotating: regulates hot spots

Pricking:

(egg yolks ; potatoes; casing) To keep from exploding!

Select foods of the same size:

To allow food to cook more evenly

Standing TimeStanding Time: :

Time at the end of microwaving Time at the end of microwaving

to allow food to finish cooking to allow food to finish cooking

outside of the oven. outside of the oven.

Microwave Cooking Time will Microwave Cooking Time will INCREASE with:INCREASE with:

1.) Larger size of food: EXAMPLE: small vs. large potato

2.) Larger quantity or number

EXAMPLE: 3 burritos vs. 1 burrito

Foods that should NOT be cooked in the microwaved

Eggs in a shell !!!

Pancakes-they will not brown or get a crust on them.

Canned foods –temperature does not get high enough to cook out bacteria.

Deep-fry foods- fat cannot be controlled!

Large amounts of food- Takes too long, not as efficient

ROUND containers cook more evenly because heat does not get trapped in the

corners or cause “hot spots”!