A Brewing Water Chemistry Primer

A little research reveals that there is more to calcium chloride than one at first might think. I've been looking at something in the form of prills from L.D. Carlson labeled simply "Calcium Chloride" and ACS grade Calcium Chloride Dihydrate from Hach. The first thing one notices about the prill form is that a solution of modest strength in DI water has a pH about 10. CaCl2 is a neutral salt (salt of strong acid and strong base) and so does not effect the pH of water in which it is dissolved. So there is something in this product besides calcium chloride. Whatever that something is it is considered (by ASTM E 449) to be calcium hydroxide and who is to say it isn't. IOW if I mix some sodium hydroxide with some pure calcium chloride and make a solution from the miz that solution is indistinguishable one I would make with equivalent amounts of calcium chloride, calcium hydroxide and sodium chloride. So the first thing one does in assaying a calcium chloride product is measure its alkalinity, call that calcium hydroxide and deduct the equivalent calcium from that available to chloride. More significant in the brewing application is that we often add calcium chloride to reduce mash pH. There will be a reduction because the amount of hydroxide is small but calcium chloride products like the L. D. Carlson one will not reduce it as much as we thought it would because we don't think about the hydroxide. There are other impurities as well such as chloride salts of sodium, potassium, magnesium, strontium etc. and, if there has been any exposure to air at all, water of hydration. The Hach material does not result in a high pH when dissolved - not because it is dihydrate but because, being ACS grade, it is free (for the most part) of impurities (except water of hydration which it picks up from the air if not as enthusiastically as the anhydride).

So if we buy something like the L. D. Carlson product should we consider it as the anhydride or dihydrate? And what about the pickle crisp? I don't think there is an easy answer. ASTM wants us to determine the amount of calcium chloride in an unknown by titrating against EDTA in order to find the calcium content. In other words, they want us to find out the calcium hardness of the solution. While their procedure is a little strange (addition of hydroxylamine hydrochloride and sugar) it is basically the same titration as is used for finding the hardness of water so those of you who have hardness kits could test calcium chloride with those.

I'm color blind so I don't see the end points of EDTA titrations very well and so have adapted a low range calcium test in which the test solution is dosed with special indicator and then an excess of chelant (EGTA which grabs calcium only). The amount of color change caused by the EGTA (difference between absorptions at 522 nm before and after addition) is proportional to the amount of calcium in the solution. After a lot of work building a calibration curve I measured the prills as being 78.8% calcium chloride and the dihydrate as being 59.2%. So again, it appears that the prills are the anhydride but with impurities andwater of hydration whereas the dihydrate clearly contains a fair amount of water of hydration beyond the 2. Note: it takes an analyst a few rounds to get comfortable with a new protocol just as it takes a brewer a few brews to get comfortable with a new technique (such as decoction mashing) so I don't have a lot of confidence in those numbers and I don't see that they are going to help in answering the broader question "How much calcium do I get out of a gram of calcium chloride". Pure anyhdrate is 36% calcium but it looks as if the product sold by L. D. Carlson can be as much as 20% stuff other than calcium chloride even after only relatively short contact with air. This implies that the material would be 29% calcium at the low end and 34 - 35% (based on specs for Dow Chemical's anhydrous product) at the top. Then there is the alkalinity aspect of this stuff.

If you really want to be certain, I suppose the better alternative is to get some of the dihydrate in ACS grade from a laboratory supply house but then we'd really want FCC grade for our beer (it is available).

It's probably best to just think of calcium chloride as being 29 - 35% calcium (with equivalent chloride attached) unless you have good reason to think it's dihydrate in which case reduce the range to 22 - 26%. After all is said and done I've used it in beer for years without being aware of any of this.

AJ - I really appreciate the effort you have put into trying to answer this question.

ajdelange said:

It's probably best to just think of calcium chloride as being 29 - 35% calcium (with equivalent chloride attached) unless you have good reason to think it's dihydrate in which case reduce the range to 22 - 26%. After all is said and done I've used it in beer for years without being aware of any of this.

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For me, at least, this is "good enough for government work".

Do the calculators (refering to THs, Bru'n, and Kai's) predict mash pH well when you brew; say, a ~10 SRM Maerzen with no crystal malts and no roasted malts? It's going to be just 10# Munich, 1.5# Dark Munich, and .5# Carafoam (technically a crystal malt but...should it be included as such where mash pH is concerned?). For example, Kai's calculator asks for the amount of roasted grain and for a predicted SRM; does it assume most of the color is from crystal malts if the SRM is 10 and the roast malt is 0%?

I'll likely just skip sauermalz and have lactic ready but I was just curious.

Some spreadsheets are flawed because they allow or recommend the brewer to add too many or too much mineral to their brewing water. In addition, its impossible to assess if a particular water profile is actually what was used by brewers in those locals. In the case of Bru'n Water, I performed extensive research on the current and historic sources of water in those places and studied if the current water quality could still be applied to those historic water profiles. In many cases, the water source is still what it was. In others, the town has resorted to new sources and other means of deducing what the water profile was was needed. But, the bottom line is that water quality varies and a brewer should not be trying to dial in a profile to the nearest ppm. I'd say that getting within about plus or minus 10 ppm is plently good and within 20 ppm may be OK too.

I do think that a brewer should fuss a little bit, but not get too caught up in minutia. The Sulfate/chloride ratio is a good benchmark when both SO4 and Cl are low, but some spreadsheets lead you to believe that you can just add more of an ion and achieve an acceptable ratio. That is not true. In any case, the Cl should always be below 100 ppm and your beer is probably better off with either of these ions less than 100 ppm (its OK to have high SO4 if its a hoppy beer).

Salt additions for ppm in your water is simple and easy (I mean its just inorganic aqueous chemistry). But how the interaction with the malt and the water profile effects mash pH is more complicated, depending on the malt itself, which is organic.

If you are interested in hitting pH values you must have a good pH meter (and take readings at the reference temp.). Only then can you tune in your system with your malts and your water. So, using sauermalt or lactic acid without a pH meter is shooting in the dark. Doesn't mean its going to make bad beer, but it doesn't mean its going to make good beer either.

If you are solely interested in salt additions to make hops pop or bring the malt forward stick with the spreadsheets. But know that salt additions have the potential to effect your mash pH, which can effect the quality of your beer in the end. If you think the salts may be messing with your pH, get a pH meter and use it every time you brew.

If you have soft water: dark beers (a lot of roasted malts) will be an issue in terms of pH being too low.

If you have high alkalinity water: light beers will tend to be a problem (too high pH)

***The last two lines are way over simplified***

funkswing said:

If you have soft water: dark beers (a lot of roasted malts) will be an issue in terms of pH being too low.

If you have high alkalinity water: light beers will tend to be a problem (too high pH)

***The last two lines are way over simplified***

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Yes, you are right that they were oversimplified. The last line is correct, but the first line is wrong. Its not soft water that is the problem, its low alkalinity.

Brewers need to get hardness out of their concern. The main thing we need to concern ourselves with is alkalinity and the second thing is hardness. We wouldn't care about hardness at all excepting that it is a critical component in countering alkalinity (ie. Residual Alkalinity).

funkswing said:

Salt additions for ppm in your water is simple and easy (I mean its just inorganic aqueous chemistry).

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It is very simple and easy as long as you stick to the salts of strong acids and weak bases e.g. sodium chloride, calcium sulfate, magnesium sulfate but as soon a bicarbonate gets involved (carbonic acid is a weak acid) and, if you are trying to estimate mash pH, phosphate (because malt contains a lot of phosphate) or control mash pH with phosphoric acid or lactic acid a level of complexity is added because pH has to be considered in all calculations. It's still not that complicated but the bookkeeping requirement goes way up and the complexity of spreadsheets goes up by a factor of, I'd say, 10.

Bottom line is that the minerals you put in your beer effect it in two major ways:

1. They are influential in setting mash pH
2. Just as when you add salts in cooking they have direct flavor effects.

If you don't get 1. right then there is no point in worrying about 2.

No spreadsheet out there, or ever going to be out there, can or will give you information about your mash pH that is nearly as good as what you get from a pH measurement. The model in the spreadsheet may be at the limits of human knowledge but it requires knowing the amount of every buffer in the system (water, base malt, specialty malts, sauermalz, added acid) and the pH of every buffer in order to predict mash pH accurately. You are lucky if you get a wort pH number from the maltster. So you have to rely on titration experiments done by guys like Kai to come up with an approximation. It makes sense in such a case to use a spreadsheet to estimate the mash pH and estimate the amount of acid to add but not to rely on those estimates for more than guidance. If you use a spreadsheet to calculate the amount of hot water to add to a mash to raise from protein to saccharification rest do you throw away your thermometer? Of course not. No one would think of it. Yet people blindly trust a spreadsheet's pH prediction. Until recently there was justification for this as pH meters were expensive and really finicky. Today that's changed and there is really, IMO, no reason why every brewer shouldn't own one.

bernerbrau said:

If by "primer water" you mean the water described in the OP of this thread (CaCl2 + dilution + pH control), then I think I will go for that to start, and get more sophisticated if it doesn't come out right.

You mentioned experimenting with how well the Bru'n Water spreadsheet predicts mash pH, but you didn't actually mention how good your results were. How accurate has it been?

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Pretty accurate. My actual pH is almost always a little higher than the spreadsheets I've used predict but, as I learned from using Bru'n Water, the profile given to me by the water supplier is unbalanced (this is a very nice feature imo). Last weekend was a Maerzen (mostly Munich malt) that Bru'n predicted at 5.5 and I got 5.55. I'll take it.

I also really noticed the pH shift during the boil last weekend. AJ has mentioned that when using lactic or sauermalz, boiling doesn't induce a pH drop like if you hadn't used them. When using lactic/sauermalz, my post boil pH would usually be almost exactly the same as pre-boil. Last week (no lactic/sauermalz), it dropped from 5.55 to 5.46.

ajdelange said:

Until recently there was justification for this as pH meters were expensive and really finicky. Today that's changed and there is really, IMO, no reason why every brewer shouldn't own one.

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Hmm, I have been reading exactly that - that pH meters are expensive and finnicky. That's why I was reluctant to go out and get one. What should a good pH meter cost me?

And how do I do pH adjustments exactly? Stir the mash, leave it for 10 minutes, take a sample, if it's too high add more acid malt, if it's too low add chalk, then stir and repeat until the level is right?

bernerbrau said:

Hmm, I have been reading exactly that - that pH meters are expensive and finnicky. That's why I was reluctant to go out and get one. What should a good pH meter cost me?

And how do I do pH adjustments exactly? Stir the mash, leave it for 10 minutes, take a sample, if it's too high add more acid malt, if it's too low add chalk, then stir and repeat until the level is right?

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I got the Hanna pHep 5 for ~$80, then you need two calibration solutions (4.01 and 7.01) and then an electrode storage solution. One nice thing about the pHep 5 is that you can just pour the storage solution in the cap then put the cap on. There is thread about 'Buying a pH meter' and Kai has a guide on his site as well.

Mine has been anything but finicky. Calibrates very quick and easy and is very easy to use but it's only been a few months.

bernerbrau said:

And how do I do pH adjustments exactly? Stir the mash, leave it for 10 minutes, take a sample, if it's too high add more acid malt, if it's too low add chalk, then stir and repeat until the level is right?

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Be sure to let the sample cool to room temp. before using the pH meter - using the pH meter on hot samples shortens the life of the probe (so I've heard).

IMO it's easier to make on-the-fly adjustments using lactic acid. Once you've got a feel for it you'll usually get it real close using sauermalz. I've never had to increase mash pH yet and I've made Stouts using a lot of RO dilution.

I am happy with my malt forward beers using this approach.

I am about to brew an expensive and time consuming stout and I just want to be 100% clear on my water additions based upon Ajdelange's original sticky:

I use Poland Springs, which is documented to be soft. I will use about 10 gallons of water between mashing in and the sparge for a five gallon batch. Does this mean I add 2 TSP of Calcium Chloride before the mash? Thanks for any help!

I doubt you'll be happy with just adding CaCl. That will further harden the soft water (which is good), but that water has low alkalinity and the mash pH will be far too low.

I just conducted an experiment on Monday while brewing a Dark Mild. Using RO water, all needed minerals excepting for lime were added to the mash along with the grain. The room-temp mash pH was just below 5.0. That is far too low for good tasting beer. I added portions of the amount of lime that Bru'n Water said I needed to have added. It took the full amount of lime calculated to bring the mash pH to a somewhat acceptable mash pH of 5.3. Its actually acceptable, but I prefer my darker beers to have their mash pH in the 5.4 to 5.5 range.

Lime is the preferred way to add alkalinity. But if you've only got a spoon to measure with and not a scale, then you're probably better off using chalk. I think EZ Water can help you with estimating what amount of chalk to add.

Thank you for your response.

I have a scale, so that is good news. I will look into the lime as an additional adjustment.

What I don't understand is why the use the generic primer if it's not sufficient. This is not a criticism at all - I appreciate what ajdelange has done in the sticky. I'm just curious to hear some thoughts.

If you brew with DI water
If you use Maris Otter as base malt
If you use 10% roast barley as the sole dark malt
Then you will get a mash pH of around 5.5
If you mash with water of modest alkalinity then your pH will be slightly higher.
If you follow Ashton Lewis's Irish Stout recipe (pale ale, 10% roast barley, flaked barley) as given in Michael Lewis's Stout monograph with modestly alkaline water you will get about the same pH.
If you use DI water with 20% roast barley you will get a pH close to 5.35
If you use DI water with 30% roast barley you will get a pH of close to 5.2
If you do anything else then I don't know exactly what will happen but common sense and experience (mine and others) dictates that if you keep the roast material at something close to the levels mentioned here you will probably get similar pH's.

If I put my (Ashton Lewis's really) recipe into Brun Water it predicts mash pH 5.1. I measure 5.55 every time I do this beer (± a couple of hundredths).

Martin puts a Brown into the same spreadsheet and calculates and then measures 5.0.

Bit of a discrepancy here and unfortunately it is up to you, the brewer, to decide what to do. There is really only one answer and that is not to rely on Primers or spreadsheets for more than general guidance. Buy a pH meter and use it in every brew. You will not be sorry you did.

It seems more likely from feedback here from those who have done this that you will have pH that is too high, as most beers require some acid, than low. The exception, of course, could be in dark beers, like stouts, where the dark malts can contribute quite a bit of acid. This is why the Primer does not advocate the addition of acid to stouts (or other dark beers) but does for other styles.

The Primer does not pretend to be all things to all men. It it intended to get you started and will, in most cases, get you a good beer. It really wants you to get started measuring mash pH (and the pH for other parts of the process too). I'd be willing to bet that you'd be just fine with only a CaCl2 addition but of you are using over 30% roast barley in your stout (and people do things like that) your pH could go below 5.3 and some alkali would be warranted. Even at 10% you could have low pH. I've seen Maris Otter turn in a DI mash pH of 5.6 and I've seen it turn in 5.8 (different maltsters).

If you decide to add alkali you won't ruin your beer. It just won't be as tasty as it could potentially be. And of course the same applies at the low end.

But if you really care, why take chances? Decent pH meters are available from most LHBSs at less than $100. I always point out that a pint at a good brew pub costs about $7 around here and recommend that you just brew 100/7 more pints to cover the cost of the meter.

I'll finish with A.J.'s first cannon of brewing: Never add alkali to brewing water nor to mash unless a measurement with a properly calibrated pH meter says you need to.

It's the first cannon because statistically (no formal data here of course) it seems excessively high pH is more likely to rear it's ugly head than low. If you follow the first cannon then, of course, you will have the meter to hand and can (and should) check whenever acid addition is contemplated.

Note: I do not (AFAIK) own stock in any company that manufactures or sells pH meters.

from my limited experience i have decided to hold off on the acidulated malt also until i get a PH reading.
I'm usiing RODI water and was brewing a pilsner so expecting to need acidulated added it to the grain crush. PH went to 4.8.
on the other hand, when mashing for my ususal brews (somewhat darker and stronger belgian ales) I hit 5.2 or 5.3 consistently with just the recommended CaCl and gypsum additions.

With mostly base (Pilsner) malt and 10% cara (pils or foam) you will, with RO/DI water have a mash pH of about 5.6-5.7. 2% sauermalz will lower this to about 5.4 - 5.5. 4.8 is not a reasonable number so this must have been measured with strips. They usually read 0.3 pH too low but sometimes even lower.

It is best, of course, to know what you mash pH is without sauermalz and base your sauermalz addition on that knowledge. Then make adjustments according as to what you observe in the mashtun with sauermalz.

Keep in mind that the mash pH with sauermalz plummets (could even go as low as 4.8) momentarily and then starts to rise. It is not stable at it's final pH for as much as 20 min to half an hour.

I'm using a meter but maybe miscalibrated? or perhaps I read it when it spiked low and before it regulated up... I took my reading soon after doughing in. Either case would be good for me if it means the PH wasn't truly at 4.8.
It's been fementing cold for about 8 days. Is there anything to be gained by reading PH now?

chrisdb said:

I'm using a meter but maybe miscalibrated?

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Provided that the calibration was done the same day as the reading was made and that the buffers were good, that's not likely.

chrisdb said:

.... or perhaps I read it when it spiked low and before it regulated up... I took my reading soon after doughing in.

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That's most likely the case.

chrisdb said:

It's been fementing cold for about 8 days. Is there anything to be gained by reading PH now?

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Sure. I advocate taking a pH reading going into the fermentor and then starting about 6 hrs after pitching. If you see a healthy drop at this time you will know the fermentation is underway. The very first thing the yeast do is try to establish a pH they like and this shows before any visible sign of fermentation is apparent.

The pH will continue to drop for the first couple of days and then level off. At this point there is little point in taking additional readings but I always measure the pH of the finished beer. All this data will help you monitor the progress of future brews.

This is the perspective of a engineer. You may find all this data taking more trouble than it is worth.

jkarp said:

Curious if others have any feedback yet on their water tweaks...

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ajdelange said:

Me too!

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I've adopted the baseline treatments as prescribed in the primer, most notably the addition of acid malt. My mashes have been consistently in the 5.2 - 5.4 range. I'm happy. I also have noticeably high sulfate content in my water, and AJ's recommendation to dilute with RO for noble hops has worked great for every style I brew, regardless of hop variety. My hoppy beers no longer have the "biting", almost astringent bitterness. The bitterness is still prounounced, but it seems much smoother, and more in line with the commercial styles I try to emulate. Thanks again AJ.

I'll add that I've also adopted AJ's recommendations, and my beers have definitely been better. I typically add .25 to .5 tsp of gypsum to my baseline, and I use his burton profile for my ipas and pale ales, but my beers definitely taste better since.

remilard said:

I've noticed in reading Gordon Strong's published recipes that what he does to his water is very close to what AJ would recommend (RO + CaCl for hefeweizen, RO + CaCl and gypsum for barleywine, etc).

Gordon won the AHA Ninkasi award the last three years. Hopefully he talks about water in his upcoming book on advanced brewing.

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Since the book just recently came out, one word of caution if following his advice: the water where he lives has about 400ppm of bicarbonate, and about 100ppm of total hardness, which means RO with a 90% rejection rate (typical) will result in 40ppm of bicarb and 10ppm of total hardness. My water is considerably less alkaline, so at best I just need to cut my water with RO, and even then only if I'm doing a light lager. I've won plenty of awards for IPAs to barleywines to stouts doing very little with my water other than filtering it and adding enough phosphoric acid to drop the pH into the butter zone.

Regardless of whether you use RO or go with tap, your goal should be to have as few salts in the resulting water as possible, and you should be consistent in how you treat your water from brew to brew. The numbers given in the OP as targets are fantastic advice... I think 90% of all grain brewers over-think their water, and their beers actually *suffer* as a result.

Saccharomyces said:

Most homebrew supply shops should have both lactic acid and phosphoric acid. I use lactic acid for German beer styles which traditionally would use saurmalz, and phosphoric acid for everything else since it is flavorless.

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Are you saying that phosphoric acid is an acceptable substitute for sauer malz cited in the OP? If so, how do you best determine the amount to add?

arturo7 said:

Are you saying that phosphoric acid is an acceptable substitute for sauer malz cited in the OP? If so, how do you best determine the amount to add?

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I use Palmer's spreadsheet, after the salt additions you can dial in the amount of acid to add. The lactic and phosphoric are pretty much interchangeable, the % lactic it says to use gets me close enough.

Seriously, on every brew I spend maybe two minutes plugging in the SRM, picking 4-8 grams of salt to add (for a 10 gal batch) and then adjusting the acid until it matches the target RA. I then put the amounts to add in the "Notes" section of the recipe in BeerSmith so they print out in my brewsheet. That's as much thought as I give it, and my beers turn out fine.

Saccharomyces said:

I use Palmer's spreadsheet, after the salt additions you can dial in the amount of acid to add. The lactic and phosphoric are pretty much interchangeable, the % lactic it says to use gets me close enough.

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I'm sticking with OP's method for the present. I was just curious if the phosphoric acid could be used instead 2% sauer malz.

arturo7 said:

I'm sticking with OP's method for the present. I was just curious if the phosphoric acid could be used instead 2% sauer malz.

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Certainly. I know plenty of folks who have had good success with the sauermalz, but I prefer acid since I don't know the % acid content of my malt and it doesn't store well (for some reason acidulated malt seems to attract weevils at my house).

arturo7 said:

I'm sticking with OP's method for the present. I was just curious if the phosphoric acid could be used instead 2% sauer malz.

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It can be. They're both used simply for pH adjustments... not sure what you're having an issue with.

Saccharomyces said:

...since I don't know the % acid content of my malt and it doesn't store well (for some reason acidulated malt seems to attract weevils at my house).

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That's what Gamma Plastic's Vittles Vaults are for. Needless to say a 55 lb sack of sauermalz lasts a pretty long time around here. No weevils, no loss of acidity, no rancid smells. Those things are FM for grain storage.

The big plusses with sauermalz is that it adds complexity to flavor as well as doing the pH reduction and it is so easy to calculate/measure. The 1%/0.1pH rule of thumb really seems to work. Someone will find a case where it doesn't in which case the brewer would have to adjust.