Re: Food irradiation

[denison.8@osu.edu]

Mr. Phelps writes:

>Irradiation does produce radiolysis products in foods----------this means
>free radicals of many types that do alter the food to an extent.

Yes, we're all clear on this point.  Irradiation, microwaving and cooking
with oven or stove all change the chemical composition of the food to some
extent.  Let's get past this point to the importane stuff.

>Lytic
>processes can alter the salt, NaCl in meats and introduce free chlorine
>effects, which are associated with things like dioxin formation.

This is ridiculous.  Sodium chloride exists in a loose ionic matrix of Na+
and Cl- to start with.  The difference in the electronegativity of the two
elements results in the chlorine stripping an electron from the sodium as
soon as they come together.  They tend to remain together solely due to
electrostatic effects.  Furthermore, dioxins are not simple
fall-together-at-random molecules; they are synthesized through certain
biological pathways and complex reaction sequences.  You will not get
formation of dioxins simply by irradiating already-dead organic material.

>Free
>radicals are involved in cell damage and connected to cancer processes and
>there are some bad products generated-----that one does not find in just
>heated foods.

We're also all clear on the dangers of free radicals and their connection
to the cancer process, so I think we can stop beating that dead horse, too
(I'm still of the opinion that increases in incidences of most cancers can
be attributed to better detection methods and the fact that modern medicine
is keeping more of us alive long enough for cancers to become detectable).
And since this is supposed to be a scientific forum, please don't dance
around and generalize; tell us _what_ 'bad products' are formed and cite
specific peer-reviewed studies that confirm the absence of those compounds
in 'just heated' foods.

>Unfortunately, since free radical inducement occurs in irradiated food, this
>process does alter both the quality and nutient content of enzymes.

Grab a biochemistry book and read a bit, and you'll find that enzymes have
no 'nutrient content' beyond that of being proteins.  Unless they're
carefully extracted and processed, enzymes become nothing more than spiffy
proteins when the plant or animal that produced them dies.  In the food
chain, digestive juices utterly destroy their functionality by breaking
them into little bits that the consuming animal's body will try to use
later.  Sort of like chopping down a tree -- it'll never be a tree again,
but you might be able to make something nice out of the wood.

>Many
>folks these days like their foods uncooked, ie the raw veggie eaters and
>others.    Spices that are irradiated don't taste quite as good as the
>non-irradiated types.
>
>Irradiated food does come with a cost--------just like adding nitrates or
>other preservatives to foods.   Don't think preservative methods or
>insecticides change the tastes of foods---------compare an organically grown
>tomato to one grown with fertilizers and pesticides----------most notice a
>big difference.

Again, show me the documentation.  Until I see results from reputable
double-blind studies that show notable differences in the tastes of
irradiated and organic foods, it's all just talk.  People who know ahead of
time what they're tasting bring their prejudices to the table with them, as
well as the effects (positive or negative) of whatever they ate before the
test.  It's also common knowledge that a person's sensitivity to various
tastes will vary over time, and may be influenced by the time of day,
hormone levels, stress and illness, among other things (you ever have a day
when one of your favorite foods just doesn't sound/taste good?).  Until you
control for the variables, you're tossing out opinions that are useless to
the rest of the world.

Less rhetoric, more facts!  Or go back to lurking...

J. Eric Denison
B.S. Biochemistry (12/94)
M.S. NE/HP (pending)
Nuclear Engineering Program
The Ohio State University
2030 Robinson Laboratory
206 West 18th Avenue
Columbus OH 43210
(614) 292-3681 or -1074
denison.8@osu.edu

Eric Denison
1729 Penworth Drive
Columbus OH 43229-5216
denison.8@osu.edu
(614) 433-0387


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