Calcium Chloride coming out of solution.

[Keith81]

A couple of days ago I made a calcium chloride solution using distilled water. I had it sitting on the counter in a canning jar with the lid tighened. This morning I looked at it and it appeared some had come out of solution. I assumed I didn't stir well enough so I poured it in a flask and put it on my stir plate. Two hours later and it's still cloudy like it was when I gave it a shake before pouring into the flask.

Any idea what is going on? The SG of the solution after mixing it and letting it cool was 1.146 at 60 F. Maybe I need to dilute it more? I tried searching the forums but what I read was way above my science comprehension skills (that's why I put this in General Discussion instead of Brew Science), sorry if this has been asked and answered already.

 

[Denny]

Sounds like you exceeded the level of solubility

 

[Keith81]

Thanks Denny. I'll dilute it.

 

[mabrungard]

I'm not sure that you were at the solubility limit. At 60F, you can get about 65 grams of anhydrous CaCl2 into 100 g of water and that denotes about a 39% solution that should have a gravity of around 1.4.

The other thing that the solution could have, is impurities. I wouldn't be surprised if there was a bit of chalk in that solution. I suggest decanting the clear solution off the sediment and dry the sediment somewhat. Then put a few drops of liquid acid or vinegar on the sediment and see if it bubbles. If it does, that's chalk.

If this impurity scenario does prove correct, this method of creating a CaCl2 solution (dissolve and then decant) would be a decent way of 'purifying' the solution for accurately dosing your brewing water.

 

[Keith81]

Thanks Martin. If some fall out of solution again I'll decant off of it.

 

[thekraken]

A little off topic but I'm curios what this is for?

Do you mix up these high concentration solutions and then use that to dose your brewing water instead of adding the salts directly to the mash? If so is this common practice?

 

[Keith81]

The way I understand it is that calcium chloride is pretty effective at absorbing moisture from the air causing it to lose purity and by making it into a solution with distilled water it becomes more stable.