All About Microwave

How does a Microwave Work ?

The microwave oven consists of a magnetron tube, which converts electricity into high frequency microwaves. Microwaves are a form of electromagnetic energy, like light waves or radio waves, and occupy a part of the electromagnetic spectrum. Microwaves cause food molecules to vibrate rapidly, creating friction that produces heat which then cooks the food. In other words, food cooked in a microwave simply absorbs microwave and turns their energy into thermal energy, which cooks the food. Microwaves are colourless, odourless, tasteless, and these are not radioactive.

Microwave oven is one of the most energy efficient appliances money can buy today. For example, it takes 18 times the electricity to bake a potato in a regular oven than in a microwave. Microwaves cook from the outside towards the center of the food.

Microwave ovens are faster for most cooking jobs because the energy heats the food and not the oven or the containers. They don't also heat up the kitchen, especially in the summer time like the other cooking appliances.


When was microwave first used to cook food ?

Microwaves were used during World War II as the basis for radars to detect and locate enemy aircrafts at long distances. During this time (ie) in 1945, it was accidentally discovered by an American engineer Percy Le Baron Spencer who was working with radar equipment and noticed that some candy he had in his pocket had melted. Spencer realized that it was these microwaves that had heated the candy and his body too ! He worked for Raytheon at that time, and they soon realized the potential of this discovery, and produced the first household microwave oven.

Can microwaves hurt you ?

A small amount of microwaves won't hurt you. Microwaves are anyways present all around us, in the form of satellite transmissions, cellular telephones, and even by the thermal radiation from our surroundings. A properly constructed microwave does not leak any microwaves.

Why can't I use a metal container in a microwave ?

Microwaves causes currents to flow in metals, these currents may heat the metal hot enough to cause a fire. Therefore, it is not a good idea to use metal containers in a microwave.


Time required to boil 8 ounces of room temperature (about 75F) water:

The higher the wattage of the microwave the faster the microwave cooks.

850 - 1000 watts - takes less than 2 minutes
650 - 850 watts - takes 2 - 3 minutes or less
400 - 650 watts - takes 3 - 4 minutes or less

Microwave tips to remember:

Do not use metal  pots and pans, or metal utensils.

Food is completely cooked  if  the bottom of plate feels warm in the center.

Cook small foods, under 2 inches in diameter, for less time, since the heat penetrates more quickly from all sides.

To prevent food from drying out, cover the food with a vented cover  whenever cooking or re-heating.

Always use less salt and seasoning than normal when cooking in the microwave, since this draws out the moisture and will toughen the food.  Add the salt later in the cooking process.

Use less water when microwaving,  due to the shorter cooking time.

Stir liquids periodically when microwaving, and  stir the outer sections, which cook faster, into the center of the dish and center sections to the outside. This equalizes the temperature throughout the food.

Cook dense food for more time in the microwave, since dence food cooks slower than porous food.

Arrange food with thickest parts, and bulky vegetables on outside of plate and quick-to-heat less-dense foods in the center. Spread a single serving of a main dish in an even layer on plate.

Turn large food over occasionally in the microwave, for more even cooking.

Microwave cooked food require some standing time, since they continue to cook for a few minutes after they are removed from the microwave oven.  Cover this food with  plate, waxed paper or paper towel to direct the heat back into the food.

Make sure not to block the vents of the microwave oven, or the oven will overheat.


Nutritional Guide--USDA Labels--Food Additives
Calorie Chart--Vegetable Calculator--Seasonal Fruits and Vegetables
Kitchen Section--Thamizhar Pakkam--Add Your Recipe