Some of you know that calcium chloride has a high affinity for water and will actually draw it out of the air. That changes the hydration of the mineral and can cause you to add less calcium chloride than you thought you were adding.
To avoid this water problem, it turns out that it is better to join ’em! What I mean is that we can create a calcium chloride solution that we can easily measure the strength of and not have to worry about the strength changing over time.
Calcium chloride is very soluble in water. If you take your solid calcium chloride and dissolve it in distilled water, we produce a solution that will have a higher specific gravity. That specific gravity is directly related to the strength of the solution.
For most brewers, there is a hydrometer somewhere in the brewery for checking wort and beer gravity. That instrument is all you need. One minor limitation is that most brewing hydrometers have a limited upper gravity reading, say 1.118. While you can make much higher gravity calcium chloride solutions than this, you can still work with low gravity solutions. Create a solution with the distilled water and solid calcium chloride and keep the gravity within the range of your hydrometer. Just keep adding solid calcium chloride until you are near the maximum reading capability of your hydrometer. Make sure that all the solids are fully dissolved and measure the solution’s gravity and go to Chart 7 in this document: http://www.prog-univers.com/…/pdf/CalciumChloridHandbook.pdf
Then read off what that gravity reading means in terms of the solution strength. That strength value can then be used to calculate the dose of calcium chloride that you need to achieve the calcium and chloride levels in your liquor. While the calculation is not too difficult, it may be more work than most want to contend with. Fortunately, the next supporter’s version of Bru’n Water will include the capability to use both solid and liquid forms of calcium chloride.