A couple of questions on pH solutions and endpoints:
Firstly, I was originally thinking of getting pH 4.01 and 7.01 buffer
solutions for my pH meter (as recommended by the manufacturer) but
Ive read that a third calibration point at 10.01 increases
accuracy around the TA endpoint and one at 3.01 increases accuracy
when measuring wine pH (which makes perfect sense of course). Anyone
recommend getting these extra (10.01 & 3.01) buffers, or is it not
worth it? Is it worth getting a deionized rinsing solution too?
Secondly, I know that pH 8.2 is a convention for the TA endpoint (a
convention ?because? phenolphthalein changes colour at this point) but
Ive heard of some winemakers using an endpoint convention of pH
7. European/American differences? Something else?