Geir Harris Hedemark wrote:
Rob Halgren writes:
Methanol is not produced by yeast in any significant amount, and there
isn't really a mechanism for it being created when you distill ethanol
out of a fermented beverage. At least not at temperatures you are
This can't be right. There is methanol (and heavier alcohols) in even
the finest Cognac. According to the head salesguy at Leopold Gourmel
they run their processes past the stage where you start to get
impurities in the end result on purpose because that is where the
flavour comes from. And the headache, people tell me. 
Of course there is a little methanol. But not a lot, and probably
not enough to kill somebody even if you tried pretty hard to distill it
out of a fermented mash. Of course you could heat the tar (literally)
out of it, and get all sorts of things. I think beer yeast makes some
of the higher weight alcohols as well, which certainly contribute flavor
to the end product. That is why my homebrewed beer is better than the
mega-mart kind, I use better yeast and feed it better food. I'm just
starting to figure out how to grow wine yeasts, although i make a wicked
cider *grin*
I do know that no matter how badly you screw up a batch of beer, you
won't get methanol poisoning. Actually you won't get poisoned
regardless, if it was really dangerous you wouldn't be able to stand the
smell, much less drink it. Yeast just doesn't make methanol in
significant quantities. It wouldn't take much to make a difference
though, if you were concentrating it. I'd bet that some of the methanol
and heavier alcohols in a brandy or other wine based spirit may be
coming out of the base material (the grape, the oak barrel maybe?). And
heat (distilling) plus an interesting chemical mix in the presence of
acids (which is what wine is) may lead to some further organic
chemistry. It might not be the yeast at all. I bet somebody has spent
an entire career studying this kind of chemistry. If not, somebody should.
I'm not a physician. Nor do I play one on TV. But was my
understanding (gleaned from numerous primary sources, like the internet!
*grin*) that the headache comes mainly from formaldehyde produced by
your own metabolism of the ethanol in the drink. Methanol would make it
worse, no doubt... Supposedly drinking lots of water will flush some of
that out of your body, but of course alcohol tends to dehydrate you to
begin with, increasing the effective concentration of formaldehyde (and
methanol, and deity knows what else). Doesn't keep me from enjoying a
homebrewed beer, a glass of port, or the occasional spirit, however.
Everything in moderation.
--
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http://www.msu.edu/~halgren
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2) There is always room for two more orchids
2a. See rule 1
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more orchids, obtain more credit
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