Some examples of ranges
fall 2020. . Cal Reds (14 varieties) pH 3.39 to 3.64: TA 0.28 to 0.36%: spGrav 1.082 to 1.094
fall2019. . .Cal red (13 varieties) pH 3.23 to 3.48: TA 0.44 to 0.54%: SpGrav 1.086 to 1.093: SO
2, was in the 20s
2020 Chile. . . Reds (12 varieties) pH 3.11 to 3.86: TA 0.32 to 0.50%: SpGrav 1.084 to 1.092: SO
2, 3 to 17 ppm
fall 2019. . . Cal white (9 varieties) pH 3.20 to 3.35: TA 0.36 to 0.38%: SpGrav 1.093 to 1.097: SO
2, 4 to 7 ppm
fall 2019 . . . Italy reds (9 varieties) pH 3.20 to 3.23: TA 0.55 to 0.57%: SpGrav 1.090 to 1.092: SO
2 16 to17 ppm
* as a club we collect feedback from purchasers and may have two to four results on a variety: the purpose is to act as check samples so we compare our analytical technique and equipment
* two handy buckets “California Classic” and “Uva de Chile”
*
@Steve Wargo if you were reading pH as it is fermenting
YES it will wander! Yeast produce CO
2 which drops the pH below the must level, I would expect about 0.2 units, however if you do country wines without a lot of buffering it will be more. A dirty probe can give slow readings but you say new. A thinner glass bulb gives faster readings, a sensitive probe should be able to follow the loss of CO
2 as you stir the sample.
As @sour grapes says once the fermentation is running, you can’t accurately adjust acids., ,,,,, the system is alive and moving