Factors affecting Water Chemistry Calculations (Oh no, not again!)

[Peebee]

The original thread (seven-month-old) doesn't need waking up, but to continue where it left off ...

I've been hacking away at the subject for a while now; I've not given up! It was a rant about home-brewer's careless mixing of "concentration" units with explicit units and the chaos that's resulting (like people measuring salts to accuracies of a hundredth of a gram ... and thinking it's doing any good!). It's taken me a while to collect enough to offer something more reasonable ... and that's because the errors are so deep ingrained, I couldn't help but get confused myself. I had a reason to keep hacking at it, I was getting "impossibly" low mash pHs (below 5.0).

For assistance I was (mis)using a respected water calculator ... Bru'n Water. As I do not have permission from Martin Brungard yet (?) I've to stick to pictures. The "parasitic spreadsheet" I created is perhaps "too close to the line" (not just the look and feel) to duplicate publicly?

The first thing I attempt to do is create a "baseline". I need the baseline to calculate salt additions without using "concentration" units. Anyone who attempts to measure salts to "hundredths of a gram", "tenths of a gram" or even less "accuracy" for that matter , should be taking careful note at this stage. There is no documented datum that allows the use of concentrations to define an explicit amount, so, I'll make one up! I'll use Batch Volume (with Mash Thickness as an alternative ... perhaps?) to arrive at a representative figure in the style of home-brewing of a few years back. Perhaps this will be from a time whence came the nonsensical "the mash needs 50-150ppm calcium".

In my "parasitic spreadsheet" this looks like:

I've expanded out to show the well known tabs of Bru'n Water. This is as I said: Parasitic! But no devious hacks or modifications to Brun' Water. Bubblegum Pink background seemed appropiate. This is a fraction of the entire spreadsheet. It replicates the relevant chunk of Bru'n Water (it's an abbreviation of the Bru'n Water section).

Using a Graham Wheeler's "Stout" profile, which is hefty enough to make a fairly challanging example. I'm setting the baseline at 70ppm of calcium (actually includes the tiny fraction of Magnesium "as Calcium"). 70ppm is about as high as the baseline should go: There is already alkalinity encrouching (as Calcium Hydroxide) to balance out the Calcium addition.

An important scheme is being demonstrated here: Note the very low solutes for the mash? The mash water doesn't need any more. "Sulphates to enhance hops"? This is mashing, there isn't any hops yet! So why encumber the mash with "sulphates"? (Answer: It's a history thing, nothing to do with brewing today). We have the ability to customise mash water (using RO water for instance), sulphates and the like can come later. The mashing water only needs Calcium (and Magnesium) with alkalinity to balance it to arrive at a suitable mash pH (Bru'n Water is clocking pH5.62 for this one - a London Stout remember).


That.s enough for now. Quite enough for folk to start lining up to crucify me again. Hopefully I've covered enough detail this time to let people know I'm serious about getting this pH business fixed!

 

[Peebee]

Sorry, I meant to add "Part Two" to this yesterday, but I noticed a bit of the spreadsheet I hadn't finished so I got on with that. You may notice some very small changes in the figures of the following diagrams, but they are very small! It was properly "equivalencing" the Magnesium with Calcium to clump them together, if interested ... and you probably aren't!

So, to recap: The amount of Calcium to deal with mash has been determined, based on mashing in half the Batch water and obtaining a concentration of 70ppm of Calcium. The choice of mash volume could have been different (based on "mash thickness" for example) and the concentration of Calcium lower. But I find one-half Batch Volume works well and "70ppm Calcium" was suggesting a decent mash pH for "Stout" in Bru'n Water. I could have used 35ppm and adjusted pH with acid (Phosphoric?), but as I'm aiming for 180ppm Calcium (later!) in the finished wort, I chose 70ppm (more would have required more alkalinity to balance it in the mash).

Nothing to worry the "salt addition shy" at this point. And no battling to balance alkalinity salts with the acidity excess Calcium creates. All easy-peasy like it should be. And I haven't mentioned "Normalizing" once until just then. Now the "scary" bit: That first section was the "Normalizing"!

Another couple of points I didn't mention: The Roast Grains (it's a "Stout") are being held back because of the acidity they create, and, my spreadsheet has a link at the top to Martin's newest "Water Knowledge" because the Bru'n Water link is (in my copy anyway) out-of-date. Have a read! The reason I link it is important is because, apart from "Normalizing", there is nothing I'm mentioning here that isn't already described in Martin's work.

I'll get some diagrams prepared for the next post. This lot can be posted before I forget it, lose it, just muck it up before I'm finished, etc. ...




EDIT: Damn it! Forgot the link ...
Bru'n Water - Water Knowledge

 

[Miraculix]

What is wrong with the approach "add X gram of salt to y amount of water to get z ppm of the ions that you added"?

 

[Peebee]

What is wrong with the approach "add X gram of salt to y amount of water to get z ppm of the ions that you added"?

Nothing! You've added the missing parameter: "y amount of water". Most "forget" ppm is meaningless as a quantity without the volume expressed. The example I might use is you don't reply to the question "How much vinegar do you put on your chips" with "5% acetic acid" (the concentration). So why do we bother with "ppm"?

"The mash should contain 50-150ppm calcium ions" is the most repeated bol***** I hear.

Okay, "ppm" has its place. But it's not in a bucketful of home-brewed beer! And it can get much weirder ... as I'll be attempting to illustrate ...

 

[Miraculix]

Nothing! You've added the missing parameter: "y amount of water". Most "forget" ppm is meaningless as a quantity without the volume expressed. The example I might use is you don't reply to the question "How much vinegar do you put on your chips" with "5% acetic acid" (the concentration). So why do we bother with "ppm"?

"The mash should contain 50-150ppm calcium ions" is the most repeated bol***** I hear.

Okay, "ppm" has its place. But it's not in a bucketful of home-brewed beer! And it can get much weirder ... as I'll be attempting to illustrate ...

But isn't that the normal way? How else could you get the ppm value, without the amount of water used?

 

[Miraculix]

You could literally later even boil it down to.... Boiling it down. So the amount of water minus the boil off would be the one to be used for the beer ppm while the mash ppm would be the one with the full amount of water being used.

 

[Miraculix]

Ok, I start getting your p(o)int I think.

 

[Peebee]

Next step in my spreadsheet is adapting the earlier "baseline" (half total Batch volume) to the volume intending to use in the mash (three-quarters total Batch volume). The spreadsheet had already worked out how much Calcium ion to use and will use that, because the amount of grain being mashed hasn't changed. Odd how the Calcium "ppm" changes though?

Much of the explanation is in the footnotes of the illustration (along with some spelling mistakes! I'll cure them).

Just as an extra, I'll "adapt" with the the next option available ("Full Batch Volume", not "Full BOIL Volume" because that wouldn't fit in the 30L Grainfather it's being designed for):

"46ppm Calcium"? Oh no, that's under the "50-150ppm" guidance ... I said the guidance was "bol*****" didn't I?


Back to the original adaptation (three-quarter total Batch volume), and next down is:

I was desperately trying these "minor alterations" in a bid to locate the reasons for my low mash pHs. This step didn't return any useful advance, but it did make a useful educational illustration. Ignore the "Tweaks" spin-wheel ... this illustration rips the Bru'n Water layout straight down the transistion line between "concentrations" and "explicit value". On the left are "concentrations" (as much use as a chocolate fireguard) and down the right is the values we want (how many actual grams, or millilitres, of "stuff" do we really need).

I've changed "Sparge" to "Post Mash" but I'll explain that later.


Next will be the "replacement" for Bru'n Water's "Water Adjustment" page (not really, this "parasitic spreadsheet" only runs alongside Bru'n Water). No more "bubblegum pink". Maybe?

 

[Peebee]

As a sideline, there is something in the above I might get picked up on.

I'm using Calcium Hydroxide (Lime) to adjust alkalinity. @Silver_Is_Money (in a much earlier post) clearly states that mixing Calcium Hydroxide with Sodium Bicarbonate is a bad thing. But in my low alkalinity water the reported "bicarbonate" is an equivalence, and I know the alkalinity in the water is due to the dosing the Water Company perform to manage the acidic moorland water they provide. And like most, if not all, UK Water Companies they dose with ...

Calcium Hydroxide!

So, using the arguments that Larry provides, I don't treat the water with Bicarbonate. Or I won't, I haven't started using Lime exclusively yet ... but in my desperate clammer to fix this low mash pH problem I have obtained new (not old had-it stuff) 100g bag of 95% Calcium Hydroxide.

 

[Peebee]

All that chatter above was leading to this completely over-the-top rehash of Martin's caculator:

This is expressing the situation after adding the roast malt and alkalinity salts once the main mash is complete (hence the "Late Alkalinity" box is checked). It rearranges how Bru'n Water displays the situation but still keeps the spreadsheets in parallel.

The "Post Mash" additions have been added (in the calculator - I'm not ready for reality yet!). "Add Hardness Minerals to Kettle" has been enabled on Bru'n Water, but in this "parasitic spreadsheet" will add together both "mash" and "sparge" columns and displays the cumulated value in the "sparge" (what I'm naming "post mash") column. This provides space in the "mash" column to continue displaying the "initial" additions. Because Bru'n Water doesn't work like this I have the second checkbox that'll cause the "initial additions" to relocate onto the "Water Report Input" page to keep the two spreadsheets parallel to each other. Bru'n Water gets to do something it wasn't designed to do, I get something to keep an eye on what I'm doing (I an inclined to veer off into fantasy land). (Hello ... my "Chloride" column isn't mirroring Brun Water. I'll have that to sort out. Heck, this scheme is working already ... I've got a virtual Martin peering over me shoulder!).

The mirrored "Adaptable Brewing Water" option allows the two spreadsheets to track these changes.

If the two spreadsheets are capable of showing the same information, why am I doing this? A: There's a whole lot of manual tweaking necessary to get Bru'n Water working this way. This effort ensures I do not forget any of those steps!


The one thing I might still be ignoring that might yet scupper my plans: I might be hiding behind the change to more effective Calcium Hydroxide replacement for Sodium Bicarbonate (i.e. lower quantities)? So I'll still have the same low mash pH problem? I'll see shortly.

 

[Peebee]

I straightened out the dodgy table. There was some old work in there that hadn't kept up with the developing, it wasn't very consistent either. But I'll repeat the table because it answers a question of why I want to be rid of "concentrations" and why I go to so much effort to do it:

I had to accept a 9% reduction in Graham's Chloide/Sulphate amounts, and a 67% increase in magnesium to get it to fit. But they are pretty inane changes. The table can't match the one in Bru'n Water because of the different approachs to mashing, but the bottom line matches up as it should.

Your task, if you really,really want it, is duplicate that table in a spreadsheet. All the values are "parts-per-million" (ppm) but are keeping tabs on real, explicit, amounts in the mash, boil and finished wort. As a result the equations and answers squirm about mercilessly! Good luck (I'm fairly confident anyone daft enough to take on the task will give up before they finish the Calcium column). If you try to do it, I guarentee your respect for Martin and his Bru'n Water calculator will hike up a several marks. Whereas, my reputation is about to take a hammering (but I'm used to it).

Warning: Rant coming up.

Conclusion: When you've finished purging all that "hardness" drivel (my previous campaign): Get rid of all the "concentration" garbage in home-brewing. There's no place for it, except to confuse and force daft un-necessary mistakes! Then perhaps all the demented wailing that "water chemistry" is so "hard" will come to an end. ("Water Chemistry"? What "Water Chemistry"? Most difficulties, if not all, are with straight-forward "weights and measures" and the insane use and mixing of inappropiate and out-dated units ... and I'm NOT talking about imperial and metric units.).

NOTE: I, until recently, was one of those "wailing that 'water chemistry' is so 'hard' ". I've got over it ... so can You!

 

[hottpeper13]

What ever happened to residual alkalinity being the key to achieving the pH you want? I have a work sheet from a course I took at Sieble, and it's spot on every time I use it. And no I can't link it. If I could link it I prolley would be using a program to make my beers but formulas, a calculator, a pencil and the rubber back button can make exceptional beers.

 

[Peebee]

"RA" is key, but tying "RA" down isn't a trivial affair. The "classic" Paul Kobach formula does for what he was doing. Many have spent years trying to perfect it for universally applying to beer brewing. Most all the brewing calculators use a variation of such calculations. They're all different. And then they try to link those formulas to "pH" prediction. Again, they're all different. But they all (or, all the more successful ones) end up in the right area, ...ish.

That's why what I've been working on above HAS NOTHING TO DO WITH THOSE CALCULATIONS! In fact, I'm very openly using Martin's "Bru'n Water" calculator to handle calculations in that area.

My arguments are at a much more basic level. Misuse of measurements and units. If people can't get that right, what chance have they of performing the "cleverer" stuff? Why are they using their defective ideas to tutor others?

For example: If someone can't understand why "calcium ions in a mash should be in the 50-150ppm range" (a much-repeated statement) is nonsense, they should be questioning their understanding of the subject. When it dawned on me, I certainly questioned my understanding!




I keep repeating that "50-150ppm" example. I should also be repeating that there are circumstances when it holds true. But when there are practical circumstances (such as the "Brew-in-a-Bag" technique) that proves the statement to be wanting, then continuing to quote it is very, very, wrong.