Creating a Brewing Water Calculator - the "Water Pro[pH]iler"

[PeeBee]

This is a follow-on of my "Water Defuddler" project, as started off here. But I wanted a less cryptic title and a "clean slate" to document progress on this calculator. It should perhaps be entitled "Treating Water with a Low Alkalinity for Brewing" as there's a "sticky" one in this section ("Brewing Liquor") for "High" Alkalinity: Those with "Low Alkalinity" (Extreme West and North of England, most of Wales, plus Scotland excluding the Central Belt) are often skipped over because only 5% of the British population live there (and because a good chunk of the 95%, who are brewers that is, don't understand that Low Alkalinity brewing waters create problems too).

But this project only starts with low alkalinity water because I live in Wales, I'll get around to high alkalinity later (but I will be covering "reverse osmosis" water early on, because it is "low alkalinity", often "very low alkalinity", water).

There, that'll do as an opening gambit for now ... I'll start collecting some points to kick off properly from ...

[PeeBee]

Apologies! The "I'll start collecting some points to kick off properly" is taking longer than I anticipated! But the project is still live, and I will come up with something soon. (And it will be worth the wait ... well, I would say that wouldn't I?

[PeeBee]

Meanwhile (Firstly?): I now realise why I wasn't getting much assistance with this venture, or even sympathy that I was stuck with very low mash pHs (<5.0). I was attempting to build high TDS water profiles from a base of low TDS water. High TDS profiles aren't very "trendy" these days and people with low TDS water (most of Scotland, most of Wales, far north and western fringes of England) aren't very numerous. I couldn't understand why the hordes of RO Water users (which is Low to very Low TDS) didn't chip in, but RO Water users are typically in the "craft beer" camp, which I've categorised as "trendy". If I want assistance in this project, I'm going to have to smudge those boundaries!


As I'd determined in the preceding thread (link in OP) I've to split the water treatment (and quantity calculation) of the Mash Water and the Sparge/Boil Water. The Mash Water can be low, or very low, TDS. It will need only enough Calcium to fulfil its purpose in the Mash and contain the Alkalinity required by the Mash. The "Sparge Water" (or boiler water if convenient ... i.e. a "no-sparge" mash) contains the remaining brewing salts.

The purpose of this split is so as not to have to deal with plummeting pH in the Mash (due to adding Calcium/Magnesium salts).

[PeeBee]

Before attempting to create a suitable brewing water, it's a good idea to have some grasp of how (or not!) pH is predicted in brewing water:

First off, it's not a direct conversion! (i.e. If you have x, y, z of something it won't mean you will get a pH of a, or b. or c). Don't believe anyone who tells you it does! There's plenty of argument on the Internet to back this up. My solution is however, "fool-proof"! ... Despite the chosen name, it won't be trying to predict pH accurately! It'll only attempt to indicate the value will roughly be in the right area of about pH5.2 to 5.7. Approximately the upper of that range ("dark beers) or the lower (light beers). Squeal if you want, but it's just not possible, nor is it particularly important. That should be obvious when people say calculator "A" always returns the correct answer whereas others say calculator "B" returns a much closer answer and calculator "A" is rubbish.

Most calculators have pH prediction based on calculating "residual alkalinity" ("RA"). Paul Kolbach, a German chemist, possibly coined the name during his work on the matter in the 1930s to 1950s (his original work was lost during WWII, so he redid it in the 50s). He was working with the old water analysing technology - "Hardness", plus "CaCO3" equivalents no-doubt - and for an entirely different "endpoint" - "out of the boiler" not "into the boiler" like calculated today. Despite that his work was "modified" into modern units ("Calcium" and "Magnesium" salts with Alkalinity along for the ride) and written into a modern-day formular:

RA in mEq/L = bicarbonate in mEq/L – (Calcium in mEq/L)/3.5 – (Magnesium in mEq/L)/7

"Milliequivalents" (per litre, or "mEq/L") expresses a particular element or compound in the same way as other elements (all effectively having the same "atomic weight", with electrical data, or "valence", rounded accordingly), such that it becomes a tool for calculating bonding between elements and compounds; (positive "cations" and negative "anions"). A specified amount of calcium will react with malt phosphates to release one equivalent of hydrogen ions which will neutralize one equivalent of Alkalinity. Magnesium has a similar effect but only half as effective (requires twice the amount compared to calcium). Kolbach determined in his work the amount of calcium (in mEq/L) divided by "3.5" would release that many hydrogen ions.

Kolbach was also responsible for providing a formula predicting the shift of pH from what could be measured from a mash in pure (zero alkalinity) water. In mEq/L that would be: pH shift = 0.084 * RA mEq/L

If you want to see a modern-day discussion of predicting pH of worts, try: Question about differences in calculated Mash pH shift due to mineralization - Homebrew Talk. Warning, it can severely play with your head (but it's the best summary of the subject I've seen lately).

That's a 20 year old paper. If you want something a little more recent and have no concern for your mental health, try (more recent? Couldn't find owt, so ... ): Alkalinity, Hardness, Residual Alkalinity and Malt Phosphate: Factors in the Establishment of Mash pH - themodernbrewhouse.com. A.J. deLange again.



Right enough of all that! Hopefully you take away with you the utter futility of attempting to tie down the pH to accuracies of two-decimal-places! (Often expecting to achieve it with a cheapo Chinese "pen" tester). Sometimes you'll get close to a "predicted" value, but not on the other occasions. Don't beat yourself up over it. If you're getting within 0.1pH of a "predicted" value, you are doing extraordinarily well! Spend your time trying to attain target alkalinity levels, Calcium levels and Magnesium levels in the Mash (the last two aka. "Hardness" if you still wear that millstone round your neck) ... that is attainable ... well of course it is, when compared with trying to attain the impossible!

[PeeBee]

As part of coming up with a simple calculator, I've got to keep in touch with the "complicated" discussions to try and ensure I don't wander too far off-track. This is a reading list, mainly for my information, no need to read them (or you might 'cos they're interesting? But they can make your brain hurt ... mine does):

Data taken into account in Brewers'Friend and BrewFather vs the data exposed by the work of Riffe and Spencer in 2018 - Homebrew Talk

Hmm ... perhaps I need to reverse my "easing off" on "RA" if it is so solidly set to a specific definition? This doesn't sit well with my assertion "RA is a thing". (Not really "my assertion" anyway, 'cos I nicked it from somewhere).

Test mash that examines the effect of strike pH on mash pH - Homebrew Talk
... Cloer to home:
P.h before mashing in




On the way to getting this far, I was posed with the following conundrum:

Indeed, your beer color (actually the malts used) influence the RA, but the RA is not a predictor of beer color.

In mathematical words: RA = f(colour) is a function, but the inverse, colour = g(RA) is not a function.

(A different forum ... THBF ... by user "Chthon"). It seems to contradict itself. But my best guess is because the "classic" Kolbach "RA" equation is missing a large chunk of information. The acidity of the grains being mashed (Kolbach only studied one grain, probably a Pilsner malt?), and grain acidity can alter greatly between grain type, due to growing conditions, and due to malting practices. The "pHDI" carry-ons mentioned in the links above are supposed to level this up, but maintaining such information is not easy! So, you can't predict colour from RA without this information, but the missing information can be determined from the final colour (after-the-event!).

The post exampled here is also suggesting "RA is a thing". Gheesh, gets complicated doesn't it!

[PeeBee]

Here's another: A Homebrewing Perspective on Mash pH - sonsofalchemy.org

I'm sure I'll find more before I'm finished (which won't be soon enough for some of you). But I need to get on (and brew some flippin' beer). What I hope to have transferred - because I'm having to come to terms with it too - is that there's a hell of a lot to predicting the outcome of Mash pH, and it takes a lot more than knowing the amounts of this and that salt and "alkalinity". You can't really rely on one person's simplified "secret formula" to judge the pH outcome; they can't even agree on a global pH range to aim for! Most will follow their "homebrew god" and believe they must aim for pH5.2 to pH5.5. Another bunch will say pH5.4 to 5.7. Depends on what part of the world you stand on, who's "gang" you belong to, how open you are to the suggestion of strangers, etc.

So, I won't be trying to tie down pH. A nice "empirical" solution (translate as "suck it and see") with some means of "tuning" the prediction (perhaps automatically?) to meet the actual outcome? Such "tuning" will need to be continually adaptable, because pH outcomes will change with time. But just get away from the "I hit target pH bang-on" brigade who are following a particular "homebrew god", because they are talking complete bo$*&%$.

But the important thing to remember, the pH is unlikely to fall into a range where the mash fails. Brewing has been successfully carried out in the past with no idea what "pH" is. We only really need to have some control over it so we can better (roughly) predict a certain outcome, and, most importantly, can be smug about the achievement.


So. You will need to get pH in the right "ballpark". To assist in that I'm taking the following steps (these are my current aims and may be subject to change because ... I may have grabbed the wrong end of a stick, etc.):

STEP 1: Divide "Batch Volume" into arbitrary amounts ... the "Mash Water" (I'm currently working on 1/2 batch volume, 2/3 batch volume and full boil volume or 1/1 batch volume); "Sparge Water" makes up the remainder (if any). The "fixed" volumes are only virtual, they'll need some additions (like "boil off", etc.) but working with these two virtual volumes will make things easier. This approach throws away any precise control of "mash thickness", but it's a vastly over-rated variable (I can hear the screams already) ... the main reason to alter "mash thickness" is "what then mash tun can handle" closely followed by "financial" (what scratches the most pennies from a given amount of grain); the former is becoming a thing of the past for homebrewers (many have "all-in-one" brewery systems now) and the latter has very limited meaning for all but the most penny-pinching home brewers.

STEP 2: Maybe modify the "Mash Volume" to account for losses. The intention is the losses are simply carried over (to boil losses) and the 1/2, 2/3, 1/1, cuts will be able to accommodate most scenarios (may need tweaking?). The important losses are "dead-space" (which is zero for an "all-in-one") and the "grain absorption" which is variable and only notable when using "full-boil-volume" mashes.

STEP 3: The water used for mashing will be "plain" (RO Water, Distilled water, Deionised water) or low mineralised water, be it tap, bottled, etc. (<35ppm Alkalinity as CaCO3). Apportion Calcium and Alkalinity salts to suit (remineralisation, see later). The amount of "Alkalinity" will need to be fairly carefully planned at this stage with Calcium (and Magnesium) limited (35ppm?) along with "Alkalinity" (35ppm as CaCO3?), hence recommending low mineralised water sources (dealing with high mineralised water sources can wait until later!).

The use of fixed mash volumes, low mineral mash water, controlled alkalinity, should be becoming apparent. The proposed calculator must deal easily with this stuff, and the result should be quite unlike other approaches (without shutting doors to approaches that might yet be useful).

STEP 4: Modify the "Sparge Volume". The most significant addition will be for "boil off", and it will depend on the system you use (and batch size? Some boilers can't keep up with boiling larger quantities too well). The boiler will also have its own "dead-space losses" to account for (including hop absorption, but less the likes of sugar, flavouring and extract volumes). The boiler will also have recoverable "dead-space" which you won't have to account for (drained hoses, squeezed hop bags, etc.). There are differences in volume due to temperature, and planned fermenter top-ups to account for too. The advantage is that the boiler volumes are more for convenience, not affecting the beer so much as with Mash Tun Volumes.

STEP 5: Unlike mineralising the mash water, dealing with the boiler water is much simpler. The majority of the salts go in at this stage; no "Alkalinity salts", possibly no accounting for Calcium added earlier. If having used a lightly mineralised water for mashing, possibly no accounting for that either (needs reviewing?). The water might be heavily mineralised water, diluted and/or mineralised as appropriate (needs reviewing?). Existing "Alkalinity" may need reducing/neutralising (acid?). And dosing of additional salts might be applied only to a presumed batch volume (i.e. post-boil)? all much easier and without the effect on mashing pH (fermenter pH might need reviewing?). Salts added direct to boil (no sparge) or to the sparge water (losses to sparged grain unimportant?).



That'll do for now (flippin' hope so ... have I seen the size of it!). All so I know what I'm doing next! But if, anyone sees anything missing ( ) I hope they'll chime in. Next, I need some "boundaries"; a "field of play" you might call it, so I can knock up some "real" examples. (Could do with a bit of colour round here too.

This is complicated while I try to link it all together, but the intention is to boil it all down into a "stroll in the park". 'Cos that's about all I'm fit for these days. And along the way get rid of all the accumulated junk from years of home-brewing ("Mashbag" will know what I mean, even if he is utterly bemused by how I'm approaching it!).

[PeeBee]

Apologies. I've been neglecting this post, due to 1: Christmas! 2: A number of awkward "realities" that this project keeps throwing at me.


I'm perhaps targeting to a very limited group of people that, like me, have very low TDS in their water but want "firm" beer structure. That's "firm" in John Palmer's "structure" sense of the word ... but he's American and declares he only knows two beers in the "firm" category with one of those being "Burton Ale", which is like counting "Lager" as only one. An example of water for the "firm" category is just about every "water profile" Graham Wheeler has ever published.

It does indicate an even bigger potential problem: If those that want to use "firm" "water profiles" inexplicably switch to RO Water. (And homebrewers do like doing inexplicable things!). Especially if, like me, they fail to notice all the extra Calcium they are adding is nudging up the "alkalinity" salts ("chalk" included!) to worrying levels. So, they fail to add all the extra "Alkalinity" (I know this because, that's what I did!). Result: pH plummets (that's the "complicated" bit; associating Calcium with Acidity in a mash).

Solution: Hold back most of the Calcium (and Magnesium) until after the Mash.

I'm not suggesting depriving the beer of Calcium. Only the mash. But not deprive the mash of Calcium completely either, just keeping Calcium at a manageable level in the mash.

[guypettigrew]

Solution: Hold back most of the Calcium (and Magnesium) until after the Mash.

I'm not suggesting depriving the beer of Calcium. Only the mash. But not deprive the mash of Calcium completely either, just keeping Calcium at a manageable level in the mash.

Numbers, please PeeBee. Thanks.

Guy

[PeeBee]

... Numbers, please PeeBee. Thanks. ...

Thank you, Guy.

Okay. I'm being poked back into action. Not that I've been inactive (on this topic), I was "researching" elsewhere (or more likely, "diverting my attention to something easier"). And I not going to get on with "numbers" this time, more waffling, the next post will start on "numbers". Even the last post was a "cheat"; a rewrite of a PM I created (apologies to the original target of it ... if you're reading this).

So, this calculator development ... the "Pro[pH]iler (I'm bored of that name already, doesn't carry the infamy and notoriety of the "Defuddler" ... which is undergoing modification BTW, so the link in my signature to it is broken for a short period. The "Defuddler II"? Anyway, the calculator is being built on to the "Defuddler" because it makes a solid base for the water calculations.

This calculator will be very different to others, because it covers users with low mineral concentrations in their source water as well (In one of them!). Don't they all? No, they don't! Neither do they get good advice from brewing forums. This calculator will not be discriminating against users of such water. Such users are in the minority, living in areas like the western and northern fringes of England, most of Wales (not the SE), most of Scotland (not the central belt) and a good section of Northern Ireland. It also includes the swelling ranks of "Reverse Osmosis" water uses. But the most critically under supported of those are those attempting to brew with highly mineralised brewing water, "traditional" British beer, not "insipid" waters users for Craft Beer" styles (which covers nearly all the "RO Water" users).

But! This calculator isn't to be discriminating. And "RO Water" is certainly being supported. At the moment "RO Water" (and bottled water and other low mineralised waters) is the only way I can support people with high mineral content source water (often described "Hard Water").

Do you have low mineralised tap water? You can often tell because water calculators tell you to add alkalinity minerals (Lime, Chalk, Baking Soda, etc.) to the brewing water, in some cases even if you attempt to brew a Lager. And, because of years of (unintentional) "discrimination", you feel reluctant to add all/any of those minerals you're being instructed to add. Adding Calcium alkalinity minerals might even exacerbate the problems! That summarises the problems I had to deal with: No help from others because they could not understand the problems I was having (statistically they were most likely "hard" water users or "Craft Beer" brewers).


When I began considering creating my own water calculator, I consulted Larry Sayre ("Silver_Is_Money", the author of the "Mash-Made-Easy" water calculator), intending to pursue the complex "DIpH" (distilled water mash pH) plus "BC" (buffering capacity) route. He talked me out of it (intensionally?) and I switched to the blindingly simple Chris Colby approach (teaspoon of this, teaspoon of that).

Unfortunately, Chris Colby's Website now appears to have gone, and his books don't appear to mention "proportional" measurements (of alkalinity especially), and "proportional" hides a lot of complexity! It's exorcising that "hidden" complexity that has caused the pause in my writeups (or, more accurately, paused my motivation!), but I've kept copies of his Web articles.

All-the-same, I'll skip past the alkalinity stuff for now, and go straight onto the easy stuff (boil water adjustments) ...