Jim writes:
< I believe lactic acid's another  byproduct of these intestinal microbes. I
wouldn't recommend drinking a couple of glasses of it a day and calling it
"paleo.">

alcohol comes from yeast fermentation, lactic acid from lactobacillus
fermentation.  Also, the lactic acid thus produced is the opposite polarity
to the lactic acid produced in exercise, and helps restrain acidic
conditions.

andrew