Hello everyone!
Recently I brewed a German Pils… Grist comprised of 10# BestMalz Pilsen, 6oz Acid Malt and 3.5oz Melanoidin, for a 5-gal batch. OG was 1.047 (exactly where it was projected), preboil gravity right on as well.
I mashed in with 4.76gal of water, (1.75 qt/lb).
Using Bru’n Water, I targeted a mash pH of 5.25… So there was 2.5 mL/gal additions of phosphoric acid as well for the mash water, (10% strength).
My (starting) water looks like this:
Ca: 37
Mg: 10
Na: 15
HCO3: 128
Sulfate: 30
Chloride: 20
Akalinity (CaCO3): 105
Total Alkalinity: 86
Water pH: 6.5
I also diluted both mash and sparge water 50/50% with distilled for this beer, then added back a few brewing salts. So my “finished” mashing water profile was:
Ca: 63
Mg: 5
Na: 8
HCO3: 20
Sulfate: 100
Chloride: 25
My question is, my mash pH was lower than expected… Right around 5.1, if not a hair less. Typically, Bru’n Water is spot on with the estimates but this time it came out lower than targeted.
Is there something with the dilution of the mash water 50/50 I missed somehow in the program? I never been that far off with the pH before, usually no more than +/- maybe .05 (and not .15!). I did calibrate my pH meter before hand and allowed the sample to cool down to room temp before checking as I always do. All measurements of acid malt, acid additions and malt were accurate as they typically are (same scales / methods). I did acidify my (batch) sparge water as well to 6.0 using about 17ml of 10% acid as well.
Any idea to prevent this from occurring in the future? Hopefully with this style it won’t affect the end result too much, but time shall tell!
Appreciate any information!