Calcium Chloride and Gypsum

[bierhaus15]

Well, they were called "Kettle Salts" for the last 150 years of brewing history, but if home brewers have decided they are to be added in the sparge water, so be it.

No offense to whomever, but I can't see a single instance where you'd not want to add the salts to the kettle (assuming they were added to the mash). I suspect this is coming from that quasi revisionist home brewing movement where calcium is no longer deemed important, yet all the supposed benefits of adding salts to the sparge water are the same benefits of adding enough Ca to the mash.

Adding salts to the sparge is not necessary if you already added enough Ca and other ions in the mash. So long as your sparge pH and alkalinity is fine, adding salts to the kettle has the side of effect of ensuring they actually end up in the wort. You'll lose 75% or more of your Ca ions in the mash/sparge, and losses to Mg, S04, and Cl are similar, albeit less important. Some are lost when added in the kettle as well, but the effect is far less.

 

[MGamber]

Saw a few older posts from Martin, and this was the main reason I've not added salts to the sparge water:

"Since we shouldn't be adding alkalinity to sparging water...you would not add minerals such as baking soda, lime, or chalk to the sparging water. The other typical minerals such as gypsum, table salt, and calcium chloride would not increase mash pH." I think the the recent years, it has been shown that as long as pH of the sparge water is in check, you shouldn't worry about extraction of tannins, so salts shouldn't play into that.

(and from a separate post)

"Now there is a drawback to adding calcium salts to the sparging water. The calcium ends up complexing with phytins from the malt. Some of that calcium is lost in the mash, but that is a minor price to pay for the benefits mentioned above."

And the benefit he mentions is that:
"For brewers using water with little mineralization, there is a clear advantage to adding calcium salts to the sparging water. The extra mineralization added to the sparging water provides a couple of benefits. The first is that the increased osmotic stress on the cells of the grain from the higher mineralization should help reduce the extraction of undesirable components like tannins and silicate from the grain. Another benefit is that extra calcium in the sparging water helps complex with oxalates from the grain and helps keep them out of the kettle."

Nice, thanks! I just started adding salts to the sparge water (been using straight RO the past couple of years) with the thinking that if the pH is in check, I can sparge hotter. Went to a pH of 5.3 and temp of 172 this time around and it's bubbling away in the fermenter. It'll be interesting to see if there's any difference in a couple weeks.

 

[couchsending]

Well, they were called "Kettle Salts" for the last 150 years of brewing history, but if home brewers have decided they are to be added in the sparge water, so be it.

No offense to whomever, but I can't see a single instance where you'd not want to add the salts to the kettle (assuming they were added to the mash). I suspect this is coming from that quasi revisionist home brewing movement where calcium is no longer deemed important, yet all the supposed benefits of adding salts to the sparge water are the same benefits of adding enough Ca to the mash.

Adding salts to the sparge is not necessary if you already added enough Ca and other ions in the mash. So long as your sparge pH and alkalinity is fine, adding salts to the kettle has the side of effect of ensuring they actually end up in the wort. You'll lose 75% or more of your Ca ions in the mash/sparge, and losses to Mg, S04, and Cl are similar, albeit less important. Some are lost when added in the kettle as well, but the effect is far less.

For sure the CL, and So4 get caught up in the grains? I had always read that you’ll lose Ca but the other ions will for the most part make it through. Also the higher you alkalinity the more Ca you lose correct?

 

[whovous]

For sure the CL, and So4 get caught up in the grains? I had always read that you’ll lose Ca but the other ions will for the most part make it through. Also the higher you alkalinity the more Ca you lose correct?

Seems kinda weird, doesn't it? English IPAs back in the day were always famous for the very hard "Burton water" they were made with. The did not get lost in the mash then, and it is hard to understand why it would get lost today.

 

[mabrungard]

Calcium is not necessary for brewing water, but it does have some benefits. Malt provides ALL the calcium that yeast needs for its metabolism, just like it does for magnesium. But calcium in the water does provide some improvement in enzyme stability and it helps remove excess oxalate and that reduces beerstone formation. But there are NO benefits in overdosing calcium into your wort and excessive calcium can actually injure or impair yeast.

While calcium can be precipitated in the mash, chloride and sulfate are completely soluble in the mash and they make it through unreduced. While it makes little difference in the resulting kettle wort concentrations, there 'might' be a benefit if salts are added to the sparging water instead of directly to the kettle due to its effect on osmotic pressure.

 

[whovous]

Calcium is not necessary for brewing water, but it does have some benefits. Malt provides ALL the calcium that yeast needs for its metabolism, just like it does for magnesium. But calcium in the water does provide some improvement in enzyme stability and it helps remove excess oxalate and that reduces beerstone formation. But there are NO benefits in overdosing calcium into your wort and excessive calcium can actually injure or impair yeast.

While calcium can be precipitated in the mash, chloride and sulfate are completely soluble in the mash and they make it through unreduced. While it makes little difference in the resulting kettle wort concentrations, there 'might' be a benefit if salts are added to the sparging water instead of directly to the kettle due to its effect on osmotic pressure.

What is osmotic pressure?

 

[cactusgarrett]

Interesting. I guess the most precise answer then is: "It depends."

I start with RO water and typically add only Gypsum and CaCl. So I guess I am one those Martin says benefits from salting the sparge water. I guess I am also guilty of being one of those who thinks that if it is the right way for me, it must be the right way for everyone. It is not.

Righto. And I'm one who uses 50/50 RO/tap water with small additions of gypsum and CaCl2, so i'm more concerned about not losing Ca in the mash if added to the sparge. Realistically, though, I'm only adding a second salt addition by means of the boil to maybe 1 in 5 batches anyway. In the grand scheme of things, this aspect doesn't matter whole lot, as beer is still being made and relatively unaffected by the different approaches.

 

[cactusgarrett]

What is osmotic pressure?

Roughly speaking, the pressure as a result of the difference of ion concentrations inside a cell versus outside. (stop me if i'm wrong, but) Martin's suggesting that salting the sparge water would make those water additions closer in ionic concentrations to the internal contents of the cells in the mash, and thus are less likely to draw out undesireables (ie. tannins) due to the reduced positive pressure the cells are exhibiting.

 

[Sauls]

1/2 cup all purpose flour? What in the world is that used for? Guess I could just google it

 

[cactusgarrett]

So not to derail @penguin69 's original post - you should add salts to the mash to achieve a specific pH, and either sparge water or the boil to hit a specific Cl:SO4 ratio or flavor/water profile. Most important (one would argue) is to hit mash pH, with the flavor aspect second. You can read up on the Cl:SO4 ratio for that.

 

[cactusgarrett]

1/2 cup all purpose flour? What in the world is that used for? Guess I could just google it

Some people add flour to provide haze for hazy IPAs. However, that's apparently an easy-out, as if other processes are executed properly, one wouldn't need that. Not to mention the point of these IPAs isn't necessarily to be hazy, but haze is just a biproduct of the production of the style.

 

[bierhaus15]

For sure the CL, and So4 get caught up in the grains? I had always read that you’ll lose Ca but the other ions will for the most part make it through. Also the higher you alkalinity the more Ca you lose correct?

It is not as straight forward as you'll lose X% of SO4 & Cl, and the malt provides some of its own (which complicates measurement), but there are losses to some extent depending on process and use of other mash additives, such as chelating agents (use brewtan much?). I didn't mean to say you'll lose 75% of those ions, as can happen with Ca, (technically it is not "lost" but carry-over is about 25-30% for mash and boil, less for sparge additions) but it is accepted there are losses.

Osmotic pressure is a total non-issue for normal brewing process and using healthy yeast, especially when home brewing. Ca begins to inhibit yeast activity above 1,000 ppm and Mg is around 25,000 ppm in wort. Plus, most yeast sees fermentation benefits up to 1,200 ppm Mg in wort, although that amount is far beyond what would be used. Per Ca, there can be issues using too much calcium when Mg is low, (>800 ppm Ca) but that amount is again above what any brewer would intentionally add.

 

[cactusgarrett]

I understood Martin's comment on osmotic pressure to be related to the mash and the exchange of ions within sparge water, not as it relates to yeast and fermentation.