How Does a Microwave Warm Food?

Water Molecules

• Like our own bodies, most food products are constructed with a very large water content. Both plant- and meat-based foods have high water percentages. It is actually the water content in those foods that is targeted in a microwave. Manipulation of the water particles is what creates the heat energy that spreads throughout the food. This is possible because of the negative and positive charge that exists on either end of a water molecule.

Microwaves

• As the name suggests, a microwave oven creates a series of microwaves that penetrate your food. As the waves penetrate the food, all the water molecules in the food begin to spin and shift. That motion results in the molecules bumping off each other. The result of that commotion is energy in the form of heat. The longer you cook your food, the more the water molecules generate heat energy and the deeper into the food the heat penetrates.

Distribution

• The distribution of heat energy in a microwave oven is not perfect. That is why the microwave needs some method of distributing the heat evenly to all of the food that in the oven. This can be done in two ways. Some models of microwave have an antenna of sorts that directs the microwaves in a circular pattern. In other microwaves, the food is placed on a platter that slowly rotates the food so that all of it is exposed evenly to the energy.

Metal

• Anyone who has ever owned a microwave has heard the warning about not putting metal in the microwave. The reason that metal cannot be put in the microwave has to do with how the machines heat food. There isn't enough water in metal to absorb heat energy. So, the microwaves either heat the metal so much it catches fire, creates electrical arcing inside the microwave or the heat reflects into the various components of the microwave itself and damages it.