Here's something interesting about the experiment that kicked off this discussion. The pH for each batch was measured:
5.68 (presumably for straight RO, based on the L-R order presented)
5.66 (presumable for the dosed batch, based on the order presented)
So here's the interesting thing. With good RO water, I'd expect a pH of about 5.67 (squarely between the two measurements taken, which really could be taken to be the same, given the precision of the meter).
With water dosed to the levels specified in the experiment, I'd expect a pH anywhere from 5.51 to 5.59, depending on the mash thickness (5.51 and 5.59 correspond to mash thicknesses of 2.0 qts/lb and 1.0 qts/lb, respectively).
There should have been a much bigger difference in mash pH between the two batches. Why wasn't there? A few possibilities come to mind.
- the salts were inadvertently not added
- the salts were not dissolved
- pH measurement error (temperature related perhaps)
If this was a matter of the salts not being added, you'd obviously expect exactly the results obtained, i.e. 3 or 4 (out of 10) of the triangle tests guessing correctly due to random chance.
<Predicted pH values above are based on MpH as implemented in BrewCipher. Other models might give slightly different predictions, but the basic phenomenon would be the same... the two pH measurements should have been much further apart.>