Yabahoobs wrote:

To a point. There would be a sigmoidal curve (freeze point-x vs.
alcohol content y) approaching, but never hitting the freeze point of
ethanol.

Yes. But this is why they put methanol in windshield washer fluid.

But yah know.. looking at the phase diagram for water, I think you
were right about the adiabatic cooling being the culprit and the
pressure differemce as the reason, especially considering that the
alcohol content of the two beers is pretty close. Incresed pressure
would normally mean it would freeze at a warmer temp. So I think I was
confused.

-klaus