So we recently got a band new reverse osmosis filter system that we use to dilute our vodka. I wanted to try an experiment using the filtered water in the mash, but I have come across a problem that has got me stumped. That is, the pH of the resulting mash is extremely low during fermentation.
We usually use spring water for our mash that is very basic (8.5pH). We add citric acid to our mash to it down to about 6.0pH. The filtered water has a starting pH of 6.6, so very little citric acid is needed to bring it down. However, about 2 days into the fermentation I measured the pH and it was 3.2pH. That seems very low to me. Can anyone please tell me what they think is going on with the chemistry.
Some things to note:
Mash consists of half white winter wheat, with half sugar
enzymes have been added to the wheat to extract the sugar
the temperature here is quite high 33C (91F) in the daytime
Im using a pH pen with auto temperature compensation to mesure the pH