hist-brewing: toxicbrau

[isenhour at uiuc.edu]

 Of course your alcohol can go off _after_ you crack it open...

Some toxins produced can make it through the brewing process,
historically I have read that ergot contaminated grain was made into
hallucinogenic beer, so I guess it depends on what you call a toxin.
However, some of the contaminants growing on grain today can create
gushing, but not much more.  Several craft brewers I know have done a
sour mash attempting to grow lactic and I have not heard of any lethal
or sickening effects, (or gushing) but I have tasted some miserable
failures.

I think you need to discriminate between bacteriostatic and
bacteriocidal.  The boiling process pretty much kills everything,
proper pitching makes the beer anerobic so aerobes are frustrated.
The pH change tends to discourage anerobes.  Some can grow but are not
toxic beyond the two I mentioned earlier (note that the "acid ferment"
in lambic preceeds the yeast ferment).  Finished beer in general can
be considered somewhat bacteriostatic but not really bacteriocidal.

There is evidence from small brewery analysis that yeast will tolerate
the growth of some contaminant organizms, but somehow prevents their
growth beyond a certain level, I find this very interesting.

trimming the rest of the post :)

john

217-328-0295                       Master Brewers Association of America
isenhour at uiuc.edu                   American Society of Brewing Chemists
University of Illinois/Urbana           Beer Judge Certification Program
Fermentation Science Instructor            Institute for Brewing Studies

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