Microwaving Zaps Nutrients

Discussion in 'Food and nutrition' started by John 'The Man, Oct 17, 2003.

  1. microwaving zaps nutrients http://www.nlm.nih.gov/medlineplus/news/fullstory_14319.html "United
    Press International

    Friday, October 17, 2003

    MURCIA, Spain, Oct 17, 2003 (United Press International via COMTEX) -- Microwaving raw broccoli
    drastically all but eliminates some natural health-promoting chemicals, a study reported in the
    Globe and Mail said Friday.

    Of particular note in the research was the post-microwaving disappearance of 97 percent of
    flavonoids -- substances often found in many brightly colored fruits and vegetables that are linked
    to a reduced risk of coronary heart disease, stroke and lung cancer.

    However, the study being released in the Journal of the Science of Food and Agriculture -- conducted
    by a group of Spanish government scientists in Murcia, Spain -- found boiling removed only 66
    percent of flavonoids from fresh raw broccoli, and pressure cooking leached out only 47 percent."

    SOURCE: F Vallejo, FA Tomás-Barberán, C García-Viguera. Phenolic compound contents in edible parts
    of broccoli inflorescences after domestic cooking
    http://www3.interscience.wiley.com/cgi-bin/abstract/106558884/ABSTRACT Journal of the Science of
    Food and Agriculture Volume 83, Issue 14, 2003. Pages 1511-1516

    ------------------------
    This Article Concluded:

    "Of particular note in the research was the post-microwaving disappearance of 97 percent of
    flavonoids -- substances often found in many brightly colored fruits and vegetables that are linked
    to a reduced risk of coronary heart disease, stroke and lung cancer.

    However, the study being released in the Journal of the Science of Food and Agriculture -- conducted
    by a group of Spanish government scientists in Murcia, Spain -- found boiling removed only 66
    percent of flavonoids from fresh raw broccoli, and pressure cooking leached out only 47 percent.

    Microwaving reduced other similarly desirable chemicals in broccoli by anywhere from 74 to
    87 percent.

    By far the most healthful results were obtained by the staple of French cooking -- a simple and
    quick steaming."

    ------------------------
    Comment:

    I find this news rather alarming to say the least. It appears that the healthiest way to cook
    broccoli is by steaming.
    --
    John Gohde, Achieving good Health is an Art, NOT a Science!

    Health-with-Attitude is a support group for people trying to follow a Healthy Lifestyle.
    http://groups.yahoo.com/group/Health-with-Attitude/
     
    Tags:


  2. Rk

    Rk Guest

    John 'the Man' <DeMan@fSchulman.com> wrote in message
    news:<0d40pvs49l91hor15f6t97vmqmge5i44d1@4ax.com>...
    > microwaving zaps nutrients
    >
    > scientists in Murcia, Spain -- found boiling removed only 66 percent of flavonoids from fresh raw
    > broccoli, and pressure cooking leached out only 47 percent.
    >
    > Microwaving reduced other similarly desirable chemicals in broccoli by anywhere from 74 to 87
    > percent.
    >
    > By far the most healthful results were obtained by the staple of French cooking -- a simple and
    > quick steaming."
    >
    > ------------------------
    > Comment:
    >
    > I find this news rather alarming to say the least. It appears that the healthiest way to cook
    > broccoli is by steaming.

    Maybe not. If they only measured the content in the broccoli, the implicationis the rest of the
    flavinoids were in the water it was cooked with. Without seeing the original paper, one cannot tell.
    So the conclusion might equally be that microwaving releases MORE nutrients from food, and perhaps
    makes it more bioavailable-- if one consumes the liquid it was cooked with..
     
  3. markd

    markd Guest

    Here is a related abstract, the question of it being cooked in water is important, here dry
    microwave cooking was best:

    http://makeashorterlink.com/?D36F25146

    >> scientists in Murcia, Spain -- found boiling removed only 66 percent of flavonoids from fresh raw
    >> broccoli, and pressure cooking leached out only 47 percent.
    >>
    >> Microwaving reduced other similarly desirable chemicals in broccoli by anywhere from 74 to 87
    >> percent.
    >>
    >> By far the most healthful results were obtained by the staple of French cooking -- a simple and
    >> quick steaming."
    >>
    >> ------------------------
    >> Comment:
    >>
    >> I find this news rather alarming to say the least. It appears that the healthiest way to cook
    >> broccoli is by steaming.
    >
    >Maybe not. If they only measured the content in the broccoli, the implicationis the rest of the
    >flavinoids were in the water it was cooked with. Without seeing the original paper, one cannot
    >tell. So the conclusion might equally be that microwaving releases MORE nutrients from food, and
    >perhaps makes it more bioavailable-- if one consumes the liquid it was cooked with..
     
  4. Once upon a time, our fellow RK rambled on about "Re: Microwaving Zaps Nutrients." Our champion
    De-Medicalizing in sci.med.nutrition retorts, thusly ...

    >> scientists in Murcia, Spain -- found boiling removed only 66 percent of flavonoids from fresh raw
    >> broccoli, and pressure cooking leached out only 47 percent.
    >>
    >> Microwaving reduced other similarly desirable chemicals in broccoli by anywhere from 74 to 87
    >> percent.
    >>
    >> By far the most healthful results were obtained by the staple of French cooking -- a simple and
    >> quick steaming."
    >>
    >> ------------------------
    >> Comment:
    >>
    >> I find this news rather alarming to say the least. It appears that the healthiest way to cook
    >> broccoli is by steaming.
    >
    >Maybe not. If they only measured the content in the broccoli, the implicationis the rest of the
    >flavinoids were in the water it was cooked with. Without seeing the original paper, one cannot
    >tell. So the conclusion might equally be that microwaving releases MORE nutrients from food, and
    >perhaps makes it more bioavailable-- if one consumes the liquid it was cooked with..

    I have reviewed other research and only found abstracts supporting the use of microwave cooking:
    11349895, 2775405, 3894486 & 7047080.

    I suspect the cooking method used. If you don't know what you are doing, microwave cooking can
    really kill the taste of the food cooked. Perhaps they over cooked on high heat with a dry method
    of cooking?
     
  5. Once upon a time, our fellow markd@frog-net.com rambled on about "Re: Microwaving Zaps Nutrients."
    Our champion De-Medicalizing in sci.med.nutrition retorts, thusly ...

    >Here is a related abstract, the question of it being cooked in water is important, here dry
    >microwave cooking was best:

    Depends on how you define dry microwave cooking.

    You can use microwave cooking to dehydrate foods, or make them hard as cardboard. I was referring to
    the concept of creating a natural steaming effect that keeps the foods naturally moist, but not
    swimming in fluids.
     
  6. markd

    markd Guest

    I was addressing the abstract to the question someone raised about leaching into water for any
    cooking method and if in the original article all were so cooked. Microwaving causes the water
    molecules to vibrate causing friction and heat which tends to cook a food from the insede out at the
    cellular level; sometimes causing the cells to burst.

    >Depends on how you define dry microwave cooking.
    >
    >You can use microwave cooking to dehydrate foods, or make them hard as cardboard. I was referring
    >to the concept of creating a natural steaming effect that keeps the foods naturally moist, but not
    >swimming in fluids.
     
  7. Moosh!

    Moosh! Guest

    On 18 Oct 2003 19:17:44 GMT, markd@frog-net.com posted:

    >
    >I was addressing the abstract to the question someone raised about leaching into water for any
    >cooking method and if in the original article all were so cooked. Microwaving causes the water
    >molecules to vibrate causing friction and heat which tends to cook a food from the insede out at
    >the cellular level; sometimes causing the cells to burst.

    Ain't no friction.

    Cells burst when intracellular water vapour pressure exceeds the strength of the cell membrane.
    Don't matter where this heat comes from.
     
  8. tome

    tome Guest

    On Tue, 21 Oct 2003 11:18:38 GMT, Moosh! <less@even.less> wrote:

    >On 18 Oct 2003 19:17:44 GMT, markd@frog-net.com posted:
    >
    >>
    >>I was addressing the abstract to the question someone raised about leaching into water for any
    >>cooking method and if in the original article all were so cooked. Microwaving causes the water
    >>molecules to vibrate causing friction and heat which tends to cook a food from the insede out at
    >>the cellular level; sometimes causing the cells to burst.
    >
    >Ain't no friction.
    >
    >Cells burst when intracellular water vapour pressure exceeds the strength of the cell membrane.
    >Don't matter where this heat comes from.

    If heated by boiling water or steam, without increasing the pressure, it is unlikely that the
    temperature inside the cell will get to boiling, resulting in few burst cells. Microwaving could
    continue delivering heat well above the temperature of open boiling water, and might easily result
    in ruptured cells. In this way, it may matter where the heat comes from.

    Tom
     
  9. Jay

    Jay Guest

    Dudes, Speaking as someone without a degree in any science. I often nuke my brocolli in a couple of
    tablespoons of water for 2 mins. When doing so, I'm often of the belief that I'm eating something
    not only tasty but very healthy. Rewinding to the beginning of the thread: Am I fooling myself?

    Jay

    <tome@butte.invalid> wrote in message news:f4napvg6jmfrkojne87ih9d1r9pv2f03s4@4ax.com...
    > On Tue, 21 Oct 2003 11:18:38 GMT, Moosh! <less@even.less> wrote:
    >
    > >On 18 Oct 2003 19:17:44 GMT, markd@frog-net.com posted:
    > >
    > >>
    > >>I was addressing the abstract to the question someone raised about leaching into water for any
    > >>cooking method and if in the original
    article
    > >>all were so cooked. Microwaving causes the water molecules to vibrate causing friction and heat
    > >>which tends to cook a food from the insede out at the cellular level; sometimes causing the
    > >>cells to burst.
    > >
    > >Ain't no friction.
    > >
    > >Cells burst when intracellular water vapour pressure exceeds the strength of the cell membrane.
    > >Don't matter where this heat comes from.
    >
    > If heated by boiling water or steam, without increasing the pressure, it is unlikely that the
    > temperature inside the cell will get to boiling, resulting in few burst cells. Microwaving could
    > continue delivering heat well above the temperature of open boiling water, and might easily result
    > in ruptured cells. In this way, it may matter where the heat comes from.
    >
    > Tom
     
  10. Once upon a time, our fellow Jay rambled on about "Re: Microwaving Zaps Nutrients." Our champion
    De-Medicalizing in sci.med.nutrition retorts, thusly ...

    >Am I fooling myself?

    No! Quite early on in this thread it was established the authors of that study were simply playing a
    word game.

    Cook your broccoli as part of a complete meal with rice or pasta and the flavonoids will be
    re-absorbed by your food.
    --
    John Gohde, Achieving good Nutrition is an Art, NOT a Science!

    The nutrition of eating a healthy diet is the foundation of the biomedical model of natural health.
    Weighing in at 17 webpages, Nutrition (http://www.Food.NaturalHealthPerspective.com/) is now the
    unofficial FAQ for sci.med.nutrition by default. :)
     
  11. David Wright

    David Wright Guest

    In article <Gxqlb.186667$JA5.4647037@news.xtra.co.nz>, Jay <qpr@*spamfree*xtra.co.nz> wrote:
    >Dudes, Speaking as someone without a degree in any science. I often nuke my brocolli in a couple of
    >tablespoons of water for 2 mins. When doing so, I'm often of the belief that I'm eating something
    >not only tasty but very healthy. Rewinding to the beginning of the thread: Am I fooling myself?

    Probably not. It sounded to me as though the "microwaving destroys all the nutrients" hoo-hah didn't
    really apply to cooking it the way you are.

    -- David Wright :: alphabeta at prodigy.net These are my opinions only, but they're almost always
    correct. "If I have not seen as far as others, it is because giants were standing on my
    shoulders." (Hal Abelson, MIT)
     
  12. Moosh!

    Moosh! Guest

    On Tue, 21 Oct 2003 09:28:36 -0700, tome@butte.invalid posted:

    >On Tue, 21 Oct 2003 11:18:38 GMT, Moosh! <less@even.less> wrote:
    >
    >>On 18 Oct 2003 19:17:44 GMT, markd@frog-net.com posted:
    >>
    >>>
    >>>I was addressing the abstract to the question someone raised about leaching into water for any
    >>>cooking method and if in the original article all were so cooked. Microwaving causes the water
    >>>molecules to vibrate causing friction and heat which tends to cook a food from the insede out at
    >>>the cellular level; sometimes causing the cells to burst.
    >>
    >>Ain't no friction.
    >>
    >>Cells burst when intracellular water vapour pressure exceeds the strength of the cell membrane.
    >>Don't matter where this heat comes from.
    >
    >If heated by boiling water or steam, without increasing the pressure, it is unlikely that the
    >temperature inside the cell will get to boiling, resulting in few burst cells. Microwaving could
    >continue delivering heat well above the temperature of open boiling water, and might easily result
    >in ruptured cells. In this way, it may matter where the heat comes from.
    >
    >Tom

    Nope. If the cells in the plants you are cooking don't reach boiling, they won't burst and the vege
    won't be cooked. Try eating an uncooked potato. Microwaving won't raise the temperature above
    boiling significantly until there is no water left. Simple physics.
     
  13. tome

    tome Guest

    On Thu, 23 Oct 2003 10:52:30 GMT, Moosh! <less@even.less> wrote:

    >On Tue, 21 Oct 2003 09:28:36 -0700, tome@butte.invalid posted:
    >
    >>On Tue, 21 Oct 2003 11:18:38 GMT, Moosh! <less@even.less> wrote:
    >>
    >>>On 18 Oct 2003 19:17:44 GMT, markd@frog-net.com posted:
    >>>
    >>>>
    >>>>I was addressing the abstract to the question someone raised about leaching into water for any
    >>>>cooking method and if in the original article all were so cooked. Microwaving causes the water
    >>>>molecules to vibrate causing friction and heat which tends to cook a food from the insede out at
    >>>>the cellular level; sometimes causing the cells to burst.
    >>>
    >>>Ain't no friction.
    >>>
    >>>Cells burst when intracellular water vapour pressure exceeds the strength of the cell membrane.
    >>>Don't matter where this heat comes from.
    >>
    >>If heated by boiling water or steam, without increasing the pressure, it is unlikely that the
    >>temperature inside the cell will get to boiling, resulting in few burst cells. Microwaving could
    >>continue delivering heat well above the temperature of open boiling water, and might easily result
    >>in ruptured cells. In this way, it may matter where the heat comes from.
    >>
    >>Tom
    >
    >
    >Nope. If the cells in the plants you are cooking don't reach boiling, they won't burst and the vege
    >won't be cooked.

    The pan water is reasonably pure and will boil at the usual temperature. The liquid in the cells has
    dissolved materials, and will have a higher boiling point. Thus, if heated by boiling water or
    steam, without increasing the pressure, it is unlikely that the temperature inside the cell will get
    to boiling, resulting in few burst cells.

    >Microwaving won't raise the temperature above boiling significantly until there is no water left.

    Microwaving can raise the temperature above the temperature of open boiling water, and thus cause
    the cell contents, with a higher boiling point, to boil and thus rupture more cells than would open
    boiling water temperatures.

    If we consider a few more factors, the higher temperatures of microwaving may also change the
    permeability and/or composition of the cell walls, thus allowing transport of material. The higher
    temperatures may cause additional chemical changes that would not occur at the temperature of
    boiling water.

    Thus, there are several possible reasons why it may matter where the heat comes from.

    Tom
     
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