I recently installed the new version of BrewSmith (4) and decided to try out the Water section. It is very comprehensive and seems to be thorough.
Now, for clarification, I have never done anything with my water other than to add acid to lower the pH based on data I input into Bru’n Water. Aside from that, I have done nothing.
The problem I’m having is BS4 has called for Magnesium Chloride in each of the two brews I plan on brewing soon and I cannot find Magnesium Chloride in any of the brewing supply shops – no, not even Northern Brewer! Amazon is the only place where this chemical can be found.
My question is: what purpose will this chemical serve if its not readily available in many brew shops? What am i missing here?
In 28 years and 631 batches, I’ve never needed it. I assume it’s a way of increasing chloride without increasing CA, same as Epsom increases sulfate without increasing CA. But unless it’s crazy high, more Ca isn’t gonna hurt. I’d just use calcium chloride instead.
It depends on the water you start with, but when first testing BS4 I saw the same thing because many of the water profiles have magnesium in them and my water has none. Brad found that by adding MgCl and CaOH to his list of water additions he can hit almost any desired water profile very accurately. It is very nice mathematically now, but it isn’t clear to me that it makes a big difference to the beer. I have found that I can get pretty close matches to what I want without using MgCl.
Magnesium taste like poison, even in very small amounts. Always better to just ignore magnesium additions. It’s only a problem if your source water is high in it. Otherwise, ignore. And like Denny says, if you really want the chloride or the sulfate, then add CaCl2 or gypsum instead, respectively. Calcium is flavor neutral, even in fairly high amounts, and is good for the yeast.
As for the new calculation capability in BS4….. just because you can, doesn’t mean you should.
631 batches? Day-um. No wonder you are the Yoda of homebrewing
In my years of brewing (400+ batches, professional brewing education at UC Davis, former commercial brewer), I have never even heard of MgCl2 being used as a brewing salt.
Calcium is THE singular, most relevant cation in brewing. I can’t think of any reason whatsoever to add a magnesium salt in any amount at any point of the process.
The KIS principle: Keep It Simple. Calcium chloride and gypsum (calcium sulfate) are the only salts you ever need to be concerned with in brewing…unless you are making a gose
Other than never having tasted poison (thankfully), I agree with all of the posts above. I wouldn’t bother with MgCl. I’m of the opinion that almost every water profile can be hit with either Gypsum or CaCl or both. And then either an acid or base for pH purposes, if necessary.
Also, I was always under the impression that mashed malt provides whatever Mg that may be necessary. And apparently some is beneficial to yeast health.
I’ve not used magnesium chloride in brewing…yet, but its readily available in a form that is pure. With that said, I agree that most brewing water does not need magnesium. I never bring my water’s magnesium concentration above 20 ppm and its usually less than 10. But if you’re starting with RO or distilled water, I do recommend that you do add the tiny bit of a magnesium salt to improve your yeast performance.
However having this available doesn’t make it easy to use. The chloride salts of calcium and magnesium are highly hygroscopic and they absorb moisture from the air and you’ll not readily know what their hydration state is.
Great information! Thanks Martin! I do not plan on using Magnesium Chloride at all. Which begs the question: why dos BS4 suggest it as a brewing salt when RO or Distilled water is not being used in the recipe!
