Presentation on theme: "Microwaves. 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."— Presentation transcript:
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!
Diagram of a Microwave
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 frictionheating
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.
Microwaves Microwaves are attracted to foods that are high in: water fat sugar
Microwave-able Containers Paper Plastic Glass Microwaveable Dishes
Non-Microwave-able Containers Metal Dishes with gold or silver on it.
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
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.
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 –Round containers will cook more evenly than square containers.
Microwave Safety To prevent burning yourself from microwave cooking, remember: –Foods can create hot containers –Items 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 burn