Chief Longwind Of The North
Certified/Certifiable
Ah yes; the microwave oven. How does it work? Is it safe? Does it destroy, or damage nutrients/enzymes?
Let's talk about this for a minute or two. First, microwaves are called microwaves because the frequency of electromagnetic radiation creates very short Sine Waves, or waveforms. It is the same energy used by RADAR (Radio Ranging And Detection), and television/radio waves. The only difference is th frequency, or sine waves/cycles per second (Hertz).
Low frequencies produce long sinewaves. As frequency increases, the sine waves grow shorter. Infra-red heat is another form of energy that produces heat. It is, however light energy, again in the lower frequency range.
How do microwaves create heat? - Microwaves, like all electro-magnetic energy, pass through sild objects based on their density, metallic content, and other factors. Ever notice that inside a metal structure, or in a dense forest, or even hilly terrain, your cell phone reception is weakened, or even completely gone? The trees are absorbing those radio waves produced by the tower, or in the building, the metal is doing the same.
We had a U.S. Airforce Radar base in my home town for many years. As the
parabolic dish revolved, and pointed in you direction, that Radar beam (radio wave) would create a little hum on every TV and radio for 25 miles. It was said that it's output power was so great, that if you put a cow in front of the transmitter, the whole cow would be cooked in a few minutes.
Well Microwave ovens have special electronic devises inside them (klystrons, or magnetrons) that produced the same radio frequencies as that humongous radar did, only with much less power.
As the microwave energy passes through foods, the moisture molecules inside the food is excited on a molecular level, creating friction, which in turn, creates heat. The heat cooks the food.
It has been said that microwave ovens cook the food from the inside out. Whoever started that rumor knew nothing about energy transfer. Just as with convective, conductive, or radiated heat, the food heats first on the outside. However, the microwave energy is passing through the food and so heats it more evenly, all the way through much more quickly.
About those vitamins minerals, and enzymes; The only portion of them that is affected, is that portion that is denatured by heat. For example, the is an enzyme found in pineapple that breaks down meat tissue. It is sometimes used in meat tenderizers That same enzyme will stop gelatin from setting, and so raw pineapple cannot be added to gelatin products, such as Jello, Gummy Bears, etc. Once pineapple is heated to a certain temperature, that enzyme is broken down, or denatured, and loses its ability to tenderize. As mentioned by Andy, foods cooked in the microwave, in water will lose water soluble vitamins and minerals, just as if they were boiled on the stove top.
Think of it this way; heat is heat, whether it comes from conduction where a pan sits on a coil burner, radiation (heat from oven, burning things, or radiant ceramic coils, or even induction stoves, is the property of thermal energy entering a substance. Cold is the removal of thermal energy from a substance. What causes the energy transfer really doesn't matter, though some forms of heating produce unique flavors, such as grilling over hot coals. Often the time it takes to produce the desire amount of heat is more important than the heat itself, i.e. low & slow, moist and slow, boiling, par boiling. hot and dry, etc.
I think people are confused because of the word radiation. The term is used in many forms, with each having a different meaning. When we talk about nuclear radiation, we are talking gamma rays. When the bomb is detonated, or when the power plant melts down, radioactive isotopes are spewed over a wide area. The particles are radioactive, or emitting gamma rays. The gamma radiation passes through the body, and dislodges DNA, destroys cell walls, bone tissue, and can produce severe burns. But once it passes through, it's gone. You don't become radioactive. But the dust and minute particles that are radioactive can become lodged in your clothing, hair, and on your skin. The continue emitting gamma radiation.
Electro-magnetic radiation does not disrupt DNA/RNA chains, nor does it stick to your body. There is are no particles emitted, and so, no left over radioactive particles.
Think about the word - radiate. It means to move in all directions from the center.
I know, Lon-winded. Now you know how I got my DC Moniker. I do hope this helps everyone understand microwave ovens a little better.
Seeeeya; Chief Longwind of the North
Let's talk about this for a minute or two. First, microwaves are called microwaves because the frequency of electromagnetic radiation creates very short Sine Waves, or waveforms. It is the same energy used by RADAR (Radio Ranging And Detection), and television/radio waves. The only difference is th frequency, or sine waves/cycles per second (Hertz).
Low frequencies produce long sinewaves. As frequency increases, the sine waves grow shorter. Infra-red heat is another form of energy that produces heat. It is, however light energy, again in the lower frequency range.
How do microwaves create heat? - Microwaves, like all electro-magnetic energy, pass through sild objects based on their density, metallic content, and other factors. Ever notice that inside a metal structure, or in a dense forest, or even hilly terrain, your cell phone reception is weakened, or even completely gone? The trees are absorbing those radio waves produced by the tower, or in the building, the metal is doing the same.
We had a U.S. Airforce Radar base in my home town for many years. As the
parabolic dish revolved, and pointed in you direction, that Radar beam (radio wave) would create a little hum on every TV and radio for 25 miles. It was said that it's output power was so great, that if you put a cow in front of the transmitter, the whole cow would be cooked in a few minutes.
Well Microwave ovens have special electronic devises inside them (klystrons, or magnetrons) that produced the same radio frequencies as that humongous radar did, only with much less power.
As the microwave energy passes through foods, the moisture molecules inside the food is excited on a molecular level, creating friction, which in turn, creates heat. The heat cooks the food.
It has been said that microwave ovens cook the food from the inside out. Whoever started that rumor knew nothing about energy transfer. Just as with convective, conductive, or radiated heat, the food heats first on the outside. However, the microwave energy is passing through the food and so heats it more evenly, all the way through much more quickly.
About those vitamins minerals, and enzymes; The only portion of them that is affected, is that portion that is denatured by heat. For example, the is an enzyme found in pineapple that breaks down meat tissue. It is sometimes used in meat tenderizers That same enzyme will stop gelatin from setting, and so raw pineapple cannot be added to gelatin products, such as Jello, Gummy Bears, etc. Once pineapple is heated to a certain temperature, that enzyme is broken down, or denatured, and loses its ability to tenderize. As mentioned by Andy, foods cooked in the microwave, in water will lose water soluble vitamins and minerals, just as if they were boiled on the stove top.
Think of it this way; heat is heat, whether it comes from conduction where a pan sits on a coil burner, radiation (heat from oven, burning things, or radiant ceramic coils, or even induction stoves, is the property of thermal energy entering a substance. Cold is the removal of thermal energy from a substance. What causes the energy transfer really doesn't matter, though some forms of heating produce unique flavors, such as grilling over hot coals. Often the time it takes to produce the desire amount of heat is more important than the heat itself, i.e. low & slow, moist and slow, boiling, par boiling. hot and dry, etc.
I think people are confused because of the word radiation. The term is used in many forms, with each having a different meaning. When we talk about nuclear radiation, we are talking gamma rays. When the bomb is detonated, or when the power plant melts down, radioactive isotopes are spewed over a wide area. The particles are radioactive, or emitting gamma rays. The gamma radiation passes through the body, and dislodges DNA, destroys cell walls, bone tissue, and can produce severe burns. But once it passes through, it's gone. You don't become radioactive. But the dust and minute particles that are radioactive can become lodged in your clothing, hair, and on your skin. The continue emitting gamma radiation.
Electro-magnetic radiation does not disrupt DNA/RNA chains, nor does it stick to your body. There is are no particles emitted, and so, no left over radioactive particles.
Think about the word - radiate. It means to move in all directions from the center.
I know, Lon-winded. Now you know how I got my DC Moniker. I do hope this helps everyone understand microwave ovens a little better.
Seeeeya; Chief Longwind of the North