Heating food

From: Bastiaan van Heur

What is a wave?

A wave can be described as a disturbance that travels through a substance from one place to the other.

How does a microwave heat food?

A microwave oven emits radio wave about the frequency of 2.5 gigahertz. Waves at this frequency are absorbed by water, fats and sugars and is then transformed into heat.

Ovens and Microwaves

The biggest difference between an oven and a microwave is that ovens cook from the outside to the inside. But microwaves using radio waves travels through the food heating the water, fat and sugar molecules evenly throughout the food.

How the microwave oven came to be

The microwave oven was found by accident. It started out as an invention for military purposes in world war 2. In that time it was only a tube that emitted radio waves used to track german airplane of the coast of brittain. The fact that the micro wave could be used to heat food was only discovered 7 years later by percy LeBaron spencer. He noticed that the radio wave let choclate bars melt in his pocket. The first microwave oven was about the size and weight of a refrigerator.

Benefits of using the microwave oven

It saves time

Easy to heat food

Easy to clean

You dont have to keep an eye on it

It retains nutrients and viatmins in the food

Disadvantages of a microwave oven

If you cook a broccolie you would think it is good against cancer but by microwaving it it loses the anti cancer nutrients

The microwave cooks dense food unevenly

The microwave doesn’t alow a crust to form for example if you are baking a cake

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