Calcium chloride (anhydrous) vs. calcium chloride (dihydrate)

[worlddivides]

What are these? I've never seen any brewing website sell anything EXCEPT just "Calcium chloride" without any specification. I'm assuming this is "anhydrous," but if that's the case, what's the "dihydrate"? I've always just assumed calcium chloride is calcium chloride, partially because I've never seen a brewing store selling anything other than just "calcium chloride" without any further specification, but different water profile software will calculate the brewing salts to add with "calcium chloride (anhydrous)" and "calcium chloride (dihydrate)" as completely different things, and I don't want to just add "calcium chloride" to something where I'm supposed to add one and it not be the other.

In the past I would buy RO water and adjust the water profile with brewing salts, but I'm far from an expert on the subject. While I feel like a chef when I come up with beer recipes with grains, hops, yeasts, and so on, when it comes to water chemistry, I just do whatever the program says. In the past I mainly just did whatever Bruin Water gave me. This time, I'm using Brewer's Friend's water profile calculators. I can't remember whether Bruin Water separated calcium chloride into anhydrous and dihydrate or not, but if it did, I probably just used the brewing "calcium chloride" for both without noticing the difference at all.

I looked online, but only a bunch of technical scientific websites came up without any clear explanation (I probably just don't know the right way to search).

 

[tracer bullet]

Hydro = water, anhydrous = no water, dihydrate = has some water. I think the weight changes, and so how much you use changes, but otherwise it's probably the same CaCl.

That said - wait for the experts to weigh in.

 

[day_trippr]

You pretty much nailed the crux of the issue: the anhydrous stuff sucks up moisture like it's its job, which affects the weight. Some folks take to keeping it in a dissolved state...

Cheers!

 

[marc1]

I dissolve mine in water and keep it in a bottle. You can get the actual g/L from the SG, without worrying about how much water it has absorbed from the air:

g/L = -684.57 + 175.12*SG + 509.45*SG*SG

https://www.homebrewtalk.com/threads/measuring-calcium-chloride.501377/

This way it doesn't matter what form you started with, you'll have a g/L solution that you can measure out.

 

[worlddivides]

I dissolve mine in water and keep it in a bottle. You can get the actual g/L from the SG, without worrying about how much water it has absorbed from the air:

g/L = -684.57 + 175.12*SG + 509.45*SG*SG

https://www.homebrewtalk.com/threads/measuring-calcium-chloride.501377/

This way it doesn't matter what form you started with, you'll have a g/L solution that you can measure out.

Thanks a ton. This is super helpful and very enlightening.

 

[worlddivides]

Hydro = water, anhydrous = no water, dihydrate = has some water. I think the weight changes, and so how much you use changes, but otherwise it's probably the same CaCl.

That said - wait for the experts to weigh in.

I knew that's what it meant, but I've never seen calcium chloride sold as "anhydrous" or "dihydrate" before. And while anhydrous means "no water," dyhdrate means "two molecules of water" (since "di" means "two" like how dioxide is something with two oxygen atoms). So it's either "no water" or "two molecules of water," which supposedly would be a different form of the compound. But I've been wondering how these are different, especially since I only see them sold as just "calcium chloride" without any further specification. I was unaware that the anhydrous form just massively absorbs water from the air. Marc1's post and link really helps out a ton there.

 

[Bramling Cross]

I prefer using non-iodized table salt for my chloride and gypsum for calcium and sulfates. You get a much more 3-D beer that way. Calcium chloride is the vegetable oil of brewing.

 

[worlddivides]

I prefer using non-iodized table salt for my chloride and gypsum for calcium and sulfite. You get a much more 3-D beer that way. Calcium chloride is the vegetable oil of brewing.

I use gypsum for calcium and sulfate, but I don't want to use table salt, because it adds sodium, which I do not need any more of. Hence I use calcium chloride and magnesium chloride because they do not contain sodium.

If I needed sodium, I'd have no reason to not use non-iodized table salt, though.

 

[Bramling Cross]

I use gypsum for calcium and sulfate, but I don't want to use table salt, because it adds sodium, which I do not need any more of. Hence I use calcium chloride and magnesium chloride because they do not contain sodium.

I'm not sure what your water is, but you might be surprised. Salt does beer some good, unless you've pushed those boundaries and you really, really know.

 

[worlddivides]

I'm not sure what your water is, but you might be surprised. Salt does beer some good, unless you've pushed those boundaries and you really, really know.

I'm no expert in water chemistry and brewing salts, but both Bruin Water and Brewers Friend (not to mention style guide profiles) agree that you do not want much sodium in a water profile for, say, a West Coast IPA.

 

[Bramling Cross]

So, you don't really know, right?

Try it.

I think 2g is a safe place to start in a 6gal batch. You'll like the results--just be sure to ditch the equivalent amount of calcium chloride.

 

[worlddivides]

So, you don't really know, right?

Try it.

I think 2g is a safe place to start in a 6gal batch. You'll like the results.

2 grams of table salt would get my water to around 80 mg/L of sodium, which is way above what I'm shooting for. Technically speaking, my tap water already has above the ideal for "light colored and hoppy," so I think I really want to avoid adding any sodium to the water, at least for American IPAs and APAs.

If the question of "don't know" is about my water, I do have the data for my tap water. If it's about my experience in water chemistry adjustment, then yes, I don't really know, but I do try to follow the numbers for the style.

 

[Bramling Cross]

80mg/L is a bit high, I'll agree.

 

[worlddivides]

I prefer using non-iodized table salt for my chloride and gypsum for calcium and sulfates. You get a much more 3-D beer that way. Calcium chloride is the vegetable oil of brewing.

This did make me wonder, though... You don't use vegetable oil in cooking? I'm quite a fan of olive oil, canola oil, peanut oil, soybean oil, and on and on, so the insult against calcium chloride kind of came across as a compliment. Heh.

 

[Peebee]

I got out of the "is it, isn't it" debate with Calcium Chloride ages ago. Get Calcium Chloride for Cheese! It's dissolved as a liquid. The stuff I get is 33% Calcium Chloride. That's effectively 33% anhydrous Calcium Chloride (weight/volume). It's measured out (volume), not weighed, so 100ml is 33g of Calcium Chloride anhydrous (effectively - it obviously isn't really, its swimming in water!).

Many calculators now support it. But it's easy to calculate (as above).

 

[worlddivides]

I got out of the "is it, isn't it" debate with Calcium Chloride ages ago. Get Calcium Chloride for Cheese! It's dissolved as a liquid. The stuff I get is 33% Calcium Chloride. That's effectively 33% anhydrous Calcium Chloride (weight/volume). It's measured out (volume), not weighed, so 100ml is 33g of Calcium Chloride anhydrous (effectively - it obviously isn't really, its swimming in water!).

Many calculators now support it. But it's easy to calculate (as above).

That definitely sounds super easy to calculate without having to worry about it absorbing water from the humidity in the air.

 

[VikeMan]

What are these? I've never seen any brewing website sell anything EXCEPT just "Calcium chloride" without any specification. I'm assuming this is "anhydrous," but if that's the case, what's the "dihydrate"?

If you see Calcium Chloride without any specification, it's almost certainly not anhydrous, which is expensive to produce and hard to keep that way.

The really big bags that commercial breweries buy are labeled dihydrate, from what I've seen.

 

[mabrungard]

A calcium chloride supply might be anhydrous when produced, but it doesn't want to stay that way whenever moist air contacts it. So for most of us, that means that we won't precisely know it degree of hydration.

There's mentions of liquid solutions, but even those can change through evaporation. The most stable way to store and know your calcium chloride hydration condition is to keep it in a saturated solution. Then, the strength of the solution varies with the long-term temperature of the solution. Assuming that you keep your saturated solution in a regulated temperature environment, that solution should have a fairly consistent concentration. All you have to do is mix the calcium chloride solids with distilled water and be sure that there's always a pile of the solids at the bottom of the vessel.

Adding the solids to water is an exothermic process, so you have to have a way to chill the vessel when you're adding the solids. A small ice bath should probably do. Once it stops getting hot, you just put the vessel out in your brewery space where it comes to its ambient temperature and the concentration should be relatively constant.

One problem that calcium chloride has, is with its purity. I've now been alerted to multiple cases where the calcium chloride is actually contaminated with sodium chloride. While sodium in brewing isn't really a big problem, the real problem is that the mash acidification reaction that a brewer might be counting on from that calcium chloride addition doesn't occur to the full degree. I recommend that you confirm with your supplier that their calcium chloride is pure. If you have any doubt that your supply is pure, prepare a sample bottle with distilled water and calculate a reasonable dose of calcium chloride to produce about a 100 ppm calcium concentration in the sample (it doesn't have to be precise, but you don't want your testing lab to have a problem with you supplying a much higher concentration). Send that prepared sample to a good testing lab like Ward Labs and make sure that they're using Inductively-Coupled Plasma or Gas-Chromatagraph mass spectrometry as their analysis method (Ward does). The lab report should come back with only calcium and chloride as the significant results. If there's sodium, it's time to find a new supply and to let the former supplier know that their stuff isn't pure.

 

[jerrylotto]

You can dry it out in an oven over 212 degrees F (I do it at 350F) so you can weigh it accurately (molecular weight of anhydrous is 110.98 g/mol) and then you can dissolve it in water to make a known molar solution. The dihydrate adds 36 g/mol to the weight so you are underestimating the Ca and Cl concentration if you don't know how hydrated it is.

 

[worlddivides]

Thanks, guys.

 

[mabrungard]

You can dry it out in an oven over 212 degrees F (I do it at 350F) so you can weigh it accurately (molecular weight of anhydrous is 110.98 g/mol) and then you can dissolve it in water to make a known molar solution. The dihydrate adds 36 g/mol to the weight so you are underestimating the Ca and Cl concentration if you don't know how hydrated it is.

To get that 'bound' water out of the calcium chloride molecule, you need to get the temperature between about 375F and 400F. 212F or thereabouts won't do it.

I'd rather underdeliver the amount of calcium and chloride than overdeliver. That's why I recommend that brewers calculate their CaCl2 addition based on the assumption that it's in its anhydrous form. If you're keeping your salt sealed and occasionally bake it as above, you should be safe in this assumption.

 

[mac_1103]

A calcium chloride supply might be anhydrous when produced, but it doesn't want to stay that way

Adding the solids to water is an exothermic process

If I'm not mistaken, the two most common uses of calcium chloride are as a drying agent and as a melting agent. Makes sense.

FWIW, MoreBeer says the stuff they sell is food grade anhydrous.

 

[jerrylotto]

To get that 'bound' water out of the calcium chloride molecule, you need to get the temperature between about 375F and 400F. 212F or thereabouts won't do it.

In time it will - the dihydrate melts around 350F so unless you want one solid crystal, you want to use a lower temperature.

 

[VikeMan]

Since nobody has mentioned this... if you want to be dead nuts on, make a solution and measure the gravity. Then you can calculate the concentration of CaCl2 (assuming no other significant solids) in the solution. and use the appropriate amount of solution in your recipe. The math is a PITA, but I mention it for completeness. Personally, I assume dihydrate, which is probably even underestimating the water content in many/most cases, because water content at equilibrium is going to be higher than that at typical home humidity levels. The longer that bag sits around, is opened and closed, etc., the more water it picks up, until it reaches saturation for the ambient temperature and humidity.

 

[Peebee]

Aye, use a solution! Even Martin isn't pushing it so:

... Then you can calculate the concentration of CaCl2 (assuming no other significant solids) in the solution. and use the appropriate amount of solution in your recipe. The math is a PITA, but I mention it for completeness. ...

And:

That's a snip out of my copy of Bru'n Water. Note you don't have to do any Maths ... in this case Martin has done it for you! Note: Martin's calculator says additions in grams, but for liquid it means "millilitres (bad Martin!). (And this snip was the first thing I could grab ... so 6.0mls of liquid CaCl2 is nonsense ... bad Me!).

Of course, you can't measure SG1.320 using a hydrometer. But I never use Hydrometers (useless bits of fragile tat).

Okay, start donating your silence money to me or I'll start going on about pyknometers ...

 

[Peebee]

This is the stuff I use, I'm sure you'll have something like it in USA?

https://www.amazon.co.uk/Calcium-Chloride-Solution-Cheese-Making/dp/B08N6PW33L

Note: It's "w/v" surely, not "w/w", ... there's w/w all over that snippet of Bru'n Water ... . Martin! Get here and explain yourself!!!

(Or, put me right?).

 

[505-Brewer]

A calcium chloride supply might be anhydrous when produced, but it doesn't want to stay that way whenever moist air contacts it. So for most of us, that means that we won't precisely know it degree of hydration.

There's mentions of liquid solutions, but even those can change through evaporation. The most stable way to store and know your calcium chloride hydration condition is to keep it in a saturated solution. Then, the strength of the solution varies with the long-term temperature of the solution. Assuming that you keep your saturated solution in a regulated temperature environment, that solution should have a fairly consistent concentration. All you have to do is mix the calcium chloride solids with distilled water and be sure that there's always a pile of the solids at the bottom of the vessel.

Adding the solids to water is an exothermic process, so you have to have a way to chill the vessel when you're adding the solids. A small ice bath should probably do. Once it stops getting hot, you just put the vessel out in your brewery space where it comes to its ambient temperature and the concentration should be relatively constant.

One problem that calcium chloride has, is with its purity. I've now been alerted to multiple cases where the calcium chloride is actually contaminated with sodium chloride. While sodium in brewing isn't really a big problem, the real problem is that the mash acidification reaction that a brewer might be counting on from that calcium chloride addition doesn't occur to the full degree. I recommend that you confirm with your supplier that their calcium chloride is pure. If you have any doubt that your supply is pure, prepare a sample bottle with distilled water and calculate a reasonable dose of calcium chloride to produce about a 100 ppm calcium concentration in the sample (it doesn't have to be precise, but you don't want your testing lab to have a problem with you supplying a much higher concentration). Send that prepared sample to a good testing lab like Ward Labs and make sure that they're using Inductively-Coupled Plasma or Gas-Chromatagraph mass spectrometry as their analysis method (Ward does). The lab report should come back with only calcium and chloride as the significant results. If there's sodium, it's time to find a new supply and to let the former supplier know that their stuff isn't pure.

ICP for Calcium ion yes but surely you mean ion chromatograph coupled with mass spec? Or ar you referring to GC to measure the chloride (as chlorine?)

 

[CascadesBrewer]

I use the Ball Pickle Crisp. This: https://a.co/d/5tgv8wk Is that dihydrate? I have had my jar for several years and I have not noticed any visual change.

 

[VikeMan]

I use the Ball Pickle Crisp. This: https://a.co/d/5tgv8wk Is that dihydrate? I have had my jar for several years and I have not noticed any visual change.

I don't know what hydrate Ball claims. I can't say that I've ever noticed a visual change over time in any of my CaCl2. But it's certainly picking up water, because it can't not.