Homebrew Happenings: Experiment!

Welcome back to Homebrew Happenings.  This month I’m going to do something a little bit different from the usual essay on a particular topic and go over a little experiment I ran over the last month or so.

I wanted to examine the impact that water additions can have on your brew, so I brewed up a couple of small batches to test two key additives:  Calcium Chloride, and Calcium Sulphate.  Based on what I’ve read, the general idea is that Chloride ions will increase the perception of malt in the beer, while Sulphate ions tend to accentuate the hop bitterness and perception of crispness.  The results of the experiment seem to reflect this, but more on that later.

Before adding the chemicals to my brewing water, I tracked down a copy of a Metro Vancouver water report, specifically this one: http://www.metrovancouver.org/services/water/WaterPublications/2015_Water_Quality_Annual_Report_Volume1.pdf

The water report shows what is generally known about Vancouver water, that it is, effectively, a blank slate.  From there  I used a very simple malt bill of pale and munich malts, which I hopped to 22 IBU to develop two different water profiles.

For the calcium chloride addition, I added 0.47g of the salt to the 1 gallon batch, bringing the chloride concentration to 66.38ppm.  I doughed in and mashed at 66C until the iodine test came back clean, then boiled the wort for 30 minutes.

I used the same mash temperature and boil time for the calcium sulphate addition, though it was made at boil instead of mash, as per the package instructions.  The sulphate concentration was 169.25ppm.

I chilled both batches in an ice bath, and then pitched white labs WLP001 California Ale Yeast. I put both batches into my fermentation chamber at 17C for 2 weeks, both went from 1.040 to  1.009. At this point I bottled the beers with ½ tsp dextrose per 650ml.  It should be noted that at this point both batches had that distinct green apple aroma that comes with unfinished beer, but the gravity had been stable for a week and I was in a hurry. (Getting this article ready for you!)

After another week and a half, I put the bottles in the fridge for several days, and then brought them out for tasting.  

I tried them myself, but to get a second opinion I made Renata try both without prompting her as to which was which.  The results are as follows:

Calcium Chloride addition:

  • I found the malt character to be more pronounced in relation to the calcium sulphate batch.  There was a deeper, sweeter flavour.
  • Renata found that this beer had smoother finish than the other.

Calcium Sulphate addition:

  • I found this beer to be lighter in body, with a sharper finish.
  • The hop bitterness was much more pronounced.
  • Renata’s assessment was in line with mine for this batch.

The end result of this experiment was to confirm what I have read, or maybe to be able to properly interpret it.  We read a lot about how things taste and the rich vocabulary of words surrounding flavour but I don’t know about the rest of you, but half of them are meaningless until you actually get to taste an example.  That’s why I strongly encourage this kind of experimentation; the lessons we learn from it make us better brewers.


Jesse Witoszkin






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