This past weekend I brewed twice. Both batches were Jamil’s Blonde Ale recipe. Both batches were 1 gallon batches—my first try at those. These batches were also my first two brews back after an extended hiatus that stemmed from some combination of moving, changing jobs, and pure laziness.
In the past, when I brewed more regularly, I had a lot of questions about brewing chemistry that were never fully answered. Now that I’m making a return to brewing, I hope to answer some of these questions.
The first question: Does calcium from water make any difference in finished beer?
I would like to design an experiment or a series or experiments to investigate this question. Right now, I’m at the point where I’m grasping, trying to understand the full scope of the problem.
The two beers I brewed this weekend were designed to understand how to approach this question: one brewed using only distilled water and one brewed with 50 ppm calcium added as CaCl2.
Recipe ¶
2 Gallons
Style: 6B-Light Hybrid Beer-Blonde Ale
Target Vols:
- Before Boil 1.75 Gal
- After Boil: 1.25 Gal
- At Pitching: 1.00 Gal
Target Stats:
- Efficiency: 70%
- Pre-Boil: 1.039
- Final Gravity: 1.054
- Mash Temp: 152°F
- Mash Time: 60 Minutes
- Boil Time: 60 Minutes
Fermentables:
- 2.5 lbs Rahr 2-Row
- 2 oz Briess Crystal 15
Hops:
- 7 grams US Fuggles
Yeast:
- 2 grams Safale US-05
Prep Work ¶
Since I’ve been out of the game for so long, I had a ton of prep-work to do.
First step: sanitize my 1 gallon fermenters. I opted for dry-heat sterilization. I accidentally bested the CDC’s recommendation for dry-heat sterilization since my oven is fairly out-of-control 
I held my three glass fermenters at a temp of 360°F for 1 hour.
I calibrated my kettle by marking a measuring stick 1-half-gallon at a time.
I also calibrated my pH meter using freshly prepared 7.01 and 4.01 calibration solution made from powder buffer-pillows.
I opted out of controlling dissolved oxygen this round. Between adopting a new process, brewing 2 batches in a weekend, and meticulously photographing each step—I felt I had enough on my plate.
Process ¶
- Brew in a bag (BIAB), 1 gallon, full-boil
- Heat 2 gallons water to 155°F in 3 gallon kettle
- Add crushed grain in 18“x32” large mesh straining bag
- Allow to stabilize at 152°F
- Maintain 152°F for 1 hour
- Boil remaining 1.75 gallons of wort for 60 minutes
- Chill to 65°F
- Rack to sanitized 1 gallon fermenter
- Ferment at 67°F
Batch #1 ¶
Heated 2 gallons of distilled water to 155°F and doughed-in. Initial strike was 148°F which I rapidly raised via direct fire to 152°F. I did have some trouble maintaining 152°F so mash temp ranged from around 148°F–154°F.
Mash ¶
Mash pH was 5.77—which, while predictably higher than desired, was within what I usually target (5.2–5.8). I left that pH unadjusted. Post-mash wort was fairly opaque. 
15 minutes into the mash: iodine test shows conversion, mash tastes more sweet than starchy.
30 minutes into the mash: iodine test still shows conversion. Mash looks like it’s finished converting.
45 minutes: Yup 60 minutes: OK, moving on.
Boil ¶
- Pre-boil Gravity: 1.042
- pH 5.76
Notes:
Pre-boil gravity of 1.042 which is higher than my expected. The wort does appear to have coagulated some protein at this point.
Added 7 grams of US Fuggles at 60 minutes. Not much visible hot break during the initial part of the boil.
Post-boil ¶
- F.G. 1.059
- Post-boil pH 5.72
Notes:
Dropped very clear with a clear break post-boil. Racked using a sanitized mini-autosiphon. Added 30 seconds of oxygen into fermenter head-space at the rate of 1 LPM, and shook fermenter 60 seconds.
Batch #2 ¶
Added 0.70 grams CaCl2/gallon into 2 gallons of distilled water to bring total calcium to 50 ppm. Heated water to 155°F and doughed-in. Initial strike was 149°F which I rapidly raised via direct fire to 152°F.
Mash ¶
- pH 5.53
- Temp: 152°F
Mash pH is lower, due to the added calcium. Finding it easier to control mash temperature with this batch (after some practice). Seems to have more foam on top of the mash, but that could be my imagination.
15 minutes into the mash: iodine test shows conversion, mash looks like it’s finished converting. May be lighter than previous batches.
30 minutes into the mash: iodine test once again shows conversion.
45 minutes: mmhmm 60 minutes: yezzur
Boil ¶
- Pre-boil Gravity: 1.043
- pH 5.54
Notes:
The wort is certainly clearer than previous batch. No real change in pH, once again.
Added 7 grams of US Fuggles at 60 minutes. Very nice visible hot-break.
Post-boil ¶
- F.G. 1.060
- Post-boil pH 5.49
Notes:
Dropped very clear with a clear break post-boil. Racked using a sanitized mini-autosiphon. Added 30 seconds of oxygen into fermenter head-space at the rate of 1 LPM, and shook fermenter 60 seconds.
Discussion ¶
It’s odd that neither batch’s post-boil pH was very much lower than the mash pH. I’ve always read that a beer’s pH should drop by ~0.3 pH units during boil. When this didn’t happen during the first (distilled water) batch’s boil, I assumed it had something to do with the missing calcium. That was, evidently, not the cause.
The only real difference between the two batches is that there was a visibly better hot-break in the batch with 50 ppm calcium. That and, of course, the difference in mash pH, which is expected and well-documented.
I’ll post again post-fermentation.