effects of a microwave on vegetable nutrients

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frigginwizard
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effects of a microwave on vegetable nutrients

Post by frigginwizard » Mon Jun 14, 2010 1:40 pm

I have been unable to to find a definitive answer as to what the effect of the microwave is on produce.

Any thoughts, links, etc?

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ApolytonGP
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Post by ApolytonGP » Mon Jun 14, 2010 2:15 pm

Pretty similar to steaming. The microwave works by the electrical waves interacting with the dipoles of the water molecules to move them back and forth (causing heat). You're unlikely to be changing too many structures of nutrients themselves unless you take the veggies to dessication and higher temps. In terms of nutrient retention, it's probably the best method (even better than steaming since you don't have what collects in the water). You'll get some easier digestion of some of the plants because of softening and all that.

I think it's basically pretty darn fine.

Go veggies!

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Post by frogbyte » Mon Jun 14, 2010 4:11 pm

The dipole water thing is a myth. But yes microwaving is possibly the healthiest cooking because as long as things are covered it's almost impossible to burn stuff on accident. Course you end up with rather disgusting mush to eat.

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Post by ApolytonGP » Mon Jun 14, 2010 6:41 pm

Yeah. Personally, I would use whatever appeals to you, tastewise. Sure, there are some ways of cooking veggies that are more nutritious than others, but as long as you are getting a LOT of veggies in and are doing some raw, some cooked...it'll all be good. Um...would watch out about a lot of oil or such if you are dieting.

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Post by synergy317 » Tue Jun 15, 2010 11:41 am

you destroy phyto-nutrients. I have read that steaming preserves more of them than all else.

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Post by frogbyte » Tue Jun 15, 2010 2:14 pm

As long as things are covered microwaving is the safest steaming. Well, you can also do it on a stove top with a pot of boiling water, and then another pan set inside the first pot, hovering well above, so that it's only heated by the water and not indirectly touching the burner.

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Post by Ryan A » Tue Jun 15, 2010 9:21 pm

frogbyte wrote:The dipole water thing is a myth. But yes microwaving is possibly the healthiest cooking because as long as things are covered it's almost impossible to burn stuff on accident. Course you end up with rather disgusting mush to eat.
I am sorry but the dipole of water is not a myth. It's true that the microwaves interact with more than just water dipoles but they do interact with the dipoles and that is how they create the heat.

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Post by frogbyte » Wed Jun 16, 2010 11:25 am

Yes, microwave radiation interacts with water, and the dipoles of water may contribute to absorption in some part, but the myth is that there's something special about water. Microwaves heat many materials.

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Post by ApolytonGP » Wed Jun 16, 2010 11:31 am

In most foods, it is pretty much the liquid water that gets interacted with (preferentially). Ice is harder for the waves to interact with.

f you have salt (and water), then the waves will interact very strongly with the ionic conductor. This can give you runaway heating of ham or hot dogs.

Waves will also interact with very thin layers of metal (like in a popcorn bag or the silvery surface on a pizza cooking disk. This allows higher than wate temps, so that you get crispening.

Waves can also interact with magnetic (or electrical) ferrites in special cookware.

Thick slabs of metal don't really interact with the waves (they reflect). For instance the sides of the cavity are reflectors.

Sharp edges of metal can cause sparking though.

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Post by Ryan A » Wed Jun 16, 2010 11:38 am

The dipoles are the primary mechanism for energy transfer and anything with a dipole that is free to rotate/reorient will cause heat.

I am pretty sure ice is a worse candidate than water purely because water has a high specific heat relative most things. The heat gets dispersed through the material after the dipole relaxes faster in materials with higher specific heat.

Metals (conductors) will interact differently with the EM wave and so yes I would expect different behavior from them, including reflection and different types of absorption than the dipole mechanisms in most organic tissues.

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Post by anandsr21 » Fri Jun 18, 2010 2:10 am

Try to get a Microwave with an Inverter. Cooking at a low intensity provides better cooking. Normal Microwaves cannot do that.

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Post by Jungledoc » Fri Jun 18, 2010 2:28 am

So, how about the original question? Do any of us have any idea? Probably not. I would guess that it has no significant effect on the nutrients other than making them hot. But that's just my guess.

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Post by Nevage » Fri Jun 18, 2010 8:45 am

I was taught in my nutrition lectures that apart from steaming, microwaving is the best way to cook vegetables for conserving nutritional content.

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Post by ApolytonGP » Fri Jun 18, 2010 8:49 am

I like this comment:

"But let’s not get too lost in the details. Vegetables, pretty much any way you prepare them, are good for you, and most of us don’t eat enough of them. And the microwave oven? A marvel of engineering, a miracle of convenience — and sometimes nutritionally advantageous to boot."

In this link: http://www.health.harvard.edu/fhg/updat ... tion.shtml

See also this link:

http://heraldextra.com/lifestyles/artic ... d45c5.html

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Post by frigginwizard » Fri Jun 18, 2010 9:06 am

the majority of vegetables that I eat are frozen, and I have always used the microwave to thaw them out. So I was curious, thanks for the answers guys.

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