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Re: microwave, RF heating



Wait a min. Paraffin generally refers to a mixture of alkanes C22=> C27 (wax). In
England it refers to kerosene; still a mixture of alkanes. No oxygen there.

My friend couldn't immediately tell me about the O-H density.

<<Now I suspect it's the =O in general bond that is more important. With H-O-H more
absorbing than C=O. From below we know that C-H isn't it. One can verify by trying, in
addition to waxed paper, refined mineral oil -- edible oil from the drug store.) Vege.
oils have both C=O and C-O-H, but only one each per molecule. Fats (e.g. butter) also
have both, but three each per molecule. Butter, of course, has a lot of other junk too.>>

But she did send this:

Bernie,

Wish I could help you out, but OH bond density isn't one of the things that nutritionists
study. And I know nothing
about the fundamentals of microwave cooking. A food scientist would probably know
something about this.

If it would be of interest, here are the macro-nutrients (not including vitamins and
minerals) of one large egg yolk and
one large egg white.

Yolk: 8.3 g water; 5.6 g fat; 2.8 g protein; 0 carbohydrate (& 272 mg cholesterol).
White: 29.1 g water; 0 g fat; 3.4 g protein; 0.4 g carbohydrate.

Maybe you can find out something on the Internet?

Good luck,
Jean

P.s. Proteins have a O=C-O-H (carboxylic) group also. Carbos. (generally: sugars,
starches, and cellulose) have lotsa -O-H, but not =O (usually, chiton is an exception and
it has N also)

Chuck Britton wrote:

We had a MicroWave/IR spectroscopist PhD working for us as a
long-term sub, a coupla years back.
He INSISTED that MicroWave heating is ENTIRELY a conductivity effect
and that there are NO significant resonances anywhere near the 2.4
GHz household MicroWave frequency.

After subbing for us (as a favor) he went back to his consulting
business and pulling in Federal $$$ on air emissions research.

Wax paper (paraffin) has lots of OH groups but is NOT heated!?

At 2:50 AM -0700 5/29/00, Bernard G. Cleyet & Nancy Ann Seese wrote:

I don't think conductivity has anything to do with microwave
absorption*. Water is a
rather good insulator -- Try heating a pair of glasses, one with
brine, the other
deionized water. I'll be surprised if the temps are more different
than expected due to
variations in the microwave field with position -- you have a
"carousel" oven? Both water
and fats, fatty acids, glycerides, etc. have O-H bonds whose
stretching frequency is close
to that of the oven's magnetron. Amino acids, and, therefore,
proteins, also have OH
bonds (in the carboxylic group), so they heat up too. I would
expect the heating to be
some monotonically increasing function of the density of OH bonds.
I'll ask my
nutritionist friend about the comparative densities in egg yolk and white.

bc

-. .-. .-. .-. .-. .-. .-. .-. .-. .-
\ / \ / \ N / \ C / \ S / \ S / \ M / \ / \ /
`-' `-' `-' `-' `-' `-' `-' `-' `-'
Chuck Britton Education is what is left when
britton@academic.ncssm.edu you have forgotten everything
North Carolina School of Science & Math you learned in school.
(919) 286-3366 x224 Albert Einstein, 1936