<HTML><FONT FACE=arial,helvetica><FONT SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">In a message dated 7/29/2003 9:22:39 PM Eastern Standard Time, burningb@burningbridges.com writes:<BR>
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<BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Methyl alcohol (aka wood alcohol, methanol)<BR>
actually has a lower boiling point than ethyl alcohol, 148F I think, and<BR>
will come over _first_ in a column still. Indeed the fusel oil components,<BR>
chiefly amyl alcohol, have higher boiling points. That brings up another<BR>
issue, though. If you exclude the undesirable higher boiling components<BR>
like amyl alcohol via rigorous fractional distillation, you are also<BR>
excluding the flavor and aroma components (mostly heavier esters and ethers)<BR>
that you _want_ to have in the final product. You just end up with nearly<BR>
pure ethyl alcohol/water azeotrope with little flavor-- not a very desirable<BR>
product. The point is moot though. Stills capable of precise fractionation<BR>
like this are recent inventions. In medieval times they were not just<BR>
unknown, but people wouldn't have understood them. The stills they used (and<BR>
are still used for many liquours) for the various national forms of aqua<BR>
vitae were simple pot stills called "alambics" I believe: different<BR>
components did not separate into precise fractions at precise temperatures,<BR>
rather the temperature of the distillate vapor rose in a continous curve.<BR>
They weren't capable of eliminating the contaminants you mention. And<BR>
because they weren't, while these stills are not nearly as efficient as<BR>
modern column stills and don't yield everclear strength distillate without<BR>
several redistillation steps, they do possess one enormous advantage over<BR>
fractionating stills: the esters involved in imparting a flavor are carried<BR>
over with the ethanol-enriched steam into the condenser, and thus into the<BR>
product. It's the same principle used in steam distillation, widely used to<BR>
extract essential oils from herbs. Modern fractionating stills will not<BR>
achieve that result; their only usage is to separate the undesirable<BR>
chemicals mentioned earlier, but honestly if you question drinking something<BR>
in its raw state then why on earth would you consider consuming its<BR>
distillate?<BR>
</BLOCKQUOTE><BR>
I believe the Bain Marie, or water jacket, around an alembic is pre-1600.<BR>
Scotti<BR>
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