Enzymes are proteins that help catalyze chemical reactions (e.g., breaking down long chain starches and sugars into smaller units) and each enzyme has different temperature and pH optima for ideal function.
Most of us are well-versed in the effects of mash temperature on mash enzyme activity:
Elevated mash temps (and adequate exposure times) can irreversibly denature enzymes (e.g., 170F x 20 min).
Very low mash temps means sub-optimal, or no, conversion.
I was wondering, though: What are the effect(s) of an excessively high (or low) mash pH?
Are those effects exposure time-dependent?
Are the effects "irreversible?"