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Description of the Microwave Oven
The advantages of a microwave oven:
In a conventional oven the heat radiated by the resistances or gas burners, slowly penetrates the
food from the outside to the inside. There is, therefore, a great loss of energy in the heating of the
air, oven components and recipients.
On the other hand, in microwave ovens the heat is generated in the interior of the food itself,
heating it from the inside outwards. There is therefore no loss of energy as the air, interior walls of
the oven and recipients (when adequate) do not heat up with microwaves.
In short, microwave ovens have the following advantages:
1. Save on cooking time: in general there is a 3/4 reduction of the cooking time than with
conventional methods.
2. Ultra-quick defrosting which prevents bacteria development.
3. Electricity saving.
4. Maintaining the nutritive value of the food due to the cooking time reduction.
5. Easy cleaning.
How the microwave oven works
In the microwave oven there is a high voltage valve called "Magnetron" that converts electric
energy to microwave energy. These electromagnetic waves are conducted to the inside of the
oven cavity by means of wave-guide and spread by a mode stirrer or by a turntable.
Inside the oven the microwaves spread out in all directions and are reflected by the metallic walls,
penetrating the food evenly.
Why does the food heat up?
Most food contains water, whose molecules vibrate with microwaves.
The friction between the molecules generates heat, which causes a temperature rise in the food,
defrosting it, cooking it or keeping it warm.
As the heat is formed inside the food:
- It may be cooked with little or no liquid or fat;
- Defrosting, heating or cooking in the microwave oven is quicker than in a conventional oven;
- Vitamins, minerals and nutritive substances are preserved;
- There is no change in the natural colour and smell of the food.