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Author Topic: Microwaves  (Read 4414 times)

Offline Smarties

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Microwaves
« on: 28/08/2010 05:55:08 »
Can using the microwave to heat up food destroy or deplete the food nutritional value? I heard that the Russians banned using microwaves because of all the side effects it poses. What are your thoughts?


 

Offline LeeE

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« Reply #1 on: 28/08/2010 23:59:58 »
In general, any heating of food will reduce its nutritional value.  Where did you hear that the Russians banned microwaves?
 

Offline Geezer

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« Reply #2 on: 29/08/2010 05:40:47 »
I heard that the Russians banned using microwaves because of all the side effects it poses. What are your thoughts?

I think it's baloney. Sweden, possibly. Russia, not a chance.
 

Offline Bored chemist

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« Reply #3 on: 29/08/2010 10:38:35 »
Cooking food (by any means) quite often increases it's nutritional value.
Raw grain, for example, is pretty indigestible.
 

Offline LeeE

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« Reply #4 on: 29/08/2010 13:11:31 »
Ah yes, cooking food may make it more edible, at least for us, but I don't think it can actually increase it's intrinsic nutritional value (and cooking might also be required to remove toxins, rendering something that was inedible edible, but that isn't really a nutritional issue).
 

Offline wolfekeeper

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« Reply #5 on: 29/08/2010 16:49:23 »
Microwaves are quite uneven, this means that some parts of the food may reach higher temperatures than others.

In general, if you add or have some water in the food dish this will help cook it more evenly, it then steams it.

Some foods like milk are more problematic when heated, milk in a babies bottle won't circulate the heat well and the top layer can tend to overheat.

Arranging the food to keep it as flat as possible helps a lot. Warming milk in a flat dish presumably wouldn't have these problems.
 

Offline Pumblechook

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« Reply #6 on: 30/08/2010 00:06:45 »
I thought some Uni or some establishment had done tests that showed that microwave oven retained more nutrients than conventional ovens. 

 

Offline Pumblechook

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« Reply #7 on: 30/08/2010 00:09:34 »
"""In studies at Cornell University, scientists looked at the effects of cooking on water-soluble vitamins in vegetables and found that spinach retained nearly all its folate when cooked in a microwave, but lost about 77 percent when cooked on a stove. They also found that bacon cooked by microwave has significantly lower levels of cancer-causing nitrosamines than conventionally cooked bacon.""

 

Offline wolfekeeper

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« Reply #8 on: 30/08/2010 00:23:40 »
Broccoli is a bad one though, I find if you cook that you can often get brown bits at the bottom of the stalks. I think that the weird shape acts as an antenna and concentrates the currents and it tends to overheat. If you chopped it up it would probably be OK.

http://onlinelibrary.wiley.com/doi/10.1002/jsfa.1585/abstract
 

Offline Deratep

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« Reply #9 on: 01/09/2010 10:32:26 »
Hello,pparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, distributed circuit elements and transmission-line theory are more useful methods for design and analysis.
 

Offline wolfekeeper

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« Reply #10 on: 01/09/2010 18:39:12 »
Ah yes, cooking food may make it more edible, at least for us, but I don't think it can actually increase it's intrinsic nutritional value (and cooking might also be required to remove toxins, rendering something that was inedible edible, but that isn't really a nutritional issue).
'Intrinsic' nutritional value seems to be a dubious concept, some nutrients are found to increase with the cooking process, I think that nutrition can only be understood in terms of what can be absorbed from food.
 

Offline Geezer

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Microwaves
« Reply #11 on: 02/09/2010 04:38:41 »
Hello,pparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, distributed circuit elements and transmission-line theory are more useful methods for design and analysis.

Very interesting. You wouldn't happen to be a bot by any chance?
 

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Microwaves
« Reply #11 on: 02/09/2010 04:38:41 »

 

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