We are all taught how important pH is in winemaking. A low pH makes SO2 perform better by having a larger percentage of molecular SO2, it makes bentonite settle better, it keeps bad bugs at bay, and generally is something to brag about when you are gathered around a barrel at the end of the day. All this has to do with hydrogen ions, iso-electric points, pH tolerances and lots of other stuff we have long forgotten about since learning about it.