The worlds easiest mash pH adjustment assistant method?

[ScrewyBrewer]

Since I've never used RA, and I don't believe Big Monk uses it, and I know that AJ poo-pooed it, I had no idea that MpH ever used it, let alone still requires it, and I merely surmised that it did not. It is one thing to report it (to satisfy public demand), but another to actually use it. I've never looked under the hood of MpH. I know Palmer, Kai, and EZ Water use(d) it.

As I understand it (subject to correction) , Kolbach first developed and used RA pre WW2, and since his stuff was destroyed during the war he recreated it sometime post WW2. AJ translated and published some of it. Kai realized that it was all talking about knock-out pH, and had little to nothing to do with mash pH. AJ then acknowledged that Kai had hit upon something he himself had completely missed.

Actually it looks like MpH4 just has RA as carry over from MpH3.

 

[Big Monk]

It is one thing to report it (to satisfy public demand)

I believe Riffe simple reports it

 

[Silver_Is_Money]

The next battleground to be conquered will be to verify if Kolbach's presumption of calcium and magnesium induced mEq's, with their respective molecular weight divisors of 3.5 and 7, hold true in the Mash at or for any/all levels of either of these two minerals. The numerals 3.5 and 7 in and of themselves seem so arbitrarily chosen as 'idealized' constants, as if they are merely quasi-empirically ballparking it. And who knows, these two constants (which appear too coincidentally ideal individually and even more so when seen together to be actually real) may not in reality be constants at all. Let alone that the chosen values of 3.5 and 7 seem too convenient to be true, they may even vary with mineralization levels or some other factor such as grist weight or mash density, etc..., and thereby both of these constants may actually prove to be variables.

 

[Big Monk]

The next battleground to be conquered will be to verify if Kolbach's presumption of calcium and magnesium induced mEq's, with their respective molecular weight divisors of 3.5 and 7, hold true in the Mash at or for any/all levels of either of these two minerals. The numerals 3.5 and 7 in and of themselves seem so arbitrarily chosen as 'idealized' constants, as if they are merely quasi-empirically ballparking it. And who knows, these two constants (which appear too coincidentally ideal individually and even more so when seen together to be actually real) may not in reality be constants at all. Let alone that the chosen values of 3.5 and 7 seem too convenient to be true, they may even vary with mineralization levels or some other factor such as grist weight or mash density, etc..., and thereby both of these constants may actually prove to be variables.

I have used them as variables since I adapted A.J.’s troubleshooter.

 

[IceChisel]

The next battleground to be conquered will be to verify if Kolbach's presumption of calcium and magnesium induced mEq's, with their respective molecular weight divisors of 3.5 and 7, hold true in the Mash at or for any/all levels of either of these two minerals. The numerals 3.5 and 7 in and of themselves seem so arbitrarily chosen as 'idealized' constants, as if they are merely quasi-empirically ballparking it. And who knows, these two constants (which appear too coincidentally ideal individually and even more so when seen together to be actually real) may not in reality be constants at all. Let alone that the chosen values of 3.5 and 7 seem too convenient to be true, they may even vary with mineralization levels or some other factor such as grist weight or mash density, etc..., and thereby both of these constants may actually prove to be variables.

Those numbers were recorded and developed at knockout.

Each malt would need it's own value for these numbers in the mash and given an incomplete reaction and many other variables at that stage it may require a different method(ology).

https://www.homebrewtalk.com/thread...ed-mash-ph-shift-due-to-mineralization.630539

 

[Silver_Is_Money]

An interesting blurb on the 3.5 factor for calcium induced pH drop during the mash:

Barth, R., Zaman, R., Influence of Strike Water Alkalinity and Hardness on Mash pH, J.ASBC 73(3):240-242, 2015. • Barth and Zaman determined that the 3.5 factor for calcium hardness was not even close to their data. • The factor could be as large as 7-15 based on their data for pilsner, pale ale, and Munich malts.

I have no access to this publication. But if this blurb is correct, then the actual mash pH depression induced by calcium is on the order of only 25% to 50% of what Kolbach tells us it should be. And it may be malt dependent. Does anyone have a copy whereby to verify this? This is a serious game changer!!!!

 

[Silver_Is_Money]

The above post #186 may potentially signal that the buffering factor multiplier is misplaced, and it should actually be applied not to malts/grains/adjuncts, but rather to the pH shift impact of calcium and magnesium. Hmmm???

 

[Silver_Is_Money]

More on this: https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-2015-0621-01

Measurement of the pH of small-scale barley mashes prepared with ale, Munich, and pilsner malt mashed with artificially alkalized and calcium-hardened water revealed that the classic Kolbach residual alkalinity equation needs to be modified to be applicable to mashing conditions.

Roger Barth and Rameez Zaman

 

[Silver_Is_Money]

And to think that in past editions of 'Mash Made Easy' I actually allowed the end user to vary precisely this Ca++ and Mg++ impact percentage. I'll have to give serious thought ot once again adding this capability back into 'MME'. But it is not worth attempting this until the facts of the referenced dissertation are known.

 

[Silver_Is_Money]

Here is specifically where the 'Influence of Strike Water Alkalinity and Hardness on Mash pH' article is to be found:

(2015) Journal of the American Society of Brewing Chemists: Vol. 73, No. 3, pp. 240-242

They want $51 just to read these three pages. Ouch!!!

 

[bob1852]

Have you tried it? Just click on it in post #69 way back on page 2.

No, I've been perfectly happy with the 1/2 dozen or so plug and play calculators that are out there that do the math for me...

 

[Silver_Is_Money]

The above post #186 may potentially signal that the buffering factor multiplier is misplaced, and it should actually be applied not to malts/grains/adjuncts, but rather to the pH shift impact of calcium and magnesium. Hmmm???

OK, after implementing it in a test version of MME I realize the above can't be correct. The two multipliers actually move recommended pH adjustment quantities in opposite directions. So in effect, they fight against each other.

 

[Big Monk]

OK, after implementing it in a test version of MME I realize the above can't be correct. The two multipliers actually move recommended pH adjustment quantities in opposite directions. So in effect, they fight against each other.

Right. The smaller the Kolbach denominators, the more affect Ca and Mg will have.

 

[Silver_Is_Money]

AJ often stated that in his experience the drop in Mash pH induced by Ca++ and Mg++ is measured to be about 50% of what Kolbach predicts for knock-out (the end of the boil). This would seemingly go hand in hand with the paper by Barth and Zaman, wherein the 3.5 factor for calcium would likely become ~7, and likewise the 7 factor for magnesium would likely become ~14.

 

[Big Monk]

AJ often stated that in his experience the drop in Mash pH induced by Ca++ and Mg++ is measured to be about 50% of what Kolbach predicts for knock-out (the end of the boil). This would seemingly go hand in hand with the paper by Barth and Zaman, wherein the 3.5 factor for calcium would likely become ~7, and likewise the 7 factor for magnesium would likely become ~14.

The problem is isolating this phenomenon and testing it.

 

[Silver_Is_Money]

The problem is isolating this phenomenon and testing it.

Which is what I presume that Barth and Zaman have already done for us. But I'm on a retired guys fixed income and budget, so spending the $51 required to read it and confirm is a bit of a stretch for me right now.

 

[Silver_Is_Money]

The problem is isolating this phenomenon and testing it.

I just conceived of what I believe should prove to be a valid test method. Earlier, and in another thread* of mine, I concluded that mashing in Ca++ and Mg++ mineralized zero Residual Alkalinity water (as defined by Kolbach) and identically mashing in DI water must result in the very same measured mash pH if indeed Kolbach is correct for the Ca++ divisor being 3.5 and for the Mg++ divisor being 7.

If one was to mash a sample in a highly calcium and magnesium containing water that critically balanced with added Alkalinity to a Kolbach calculated RA = 0, and also mashed a sample otherwise identical sans for using DI water, and if the mash pH's greatly differ thereby, then proper revisions for 3.5 and 7 would emerge from this difference in pH. And to give the emerging new divisors more confidence, the side by side experiment should be done at least in triplicate. And to verify if calcium and magnesium clash in any way, the triplicates should themselves be trippled such as that set 1 would involve only Ca++, set 2 would involve only Mg++, and set 3 would involve a blend of Ca++ and Mg++. In this way the individual Ca++ and Mg++ divisor factors will better emerge also.

*In that thread I was already touching upon this.

 

[Silver_Is_Money]

I would initially suggest trying 75 ppm Ca++ and 15 ppm Mg++ (balanced with Alkalinity) for the respective zero RA waters. Then I would suggest a repeat of every test via bumping these to 150 ppm and 30 ppm respectfully, followed by another repeat via bumping them to 300 ppm and 60 ppm respectfully, as this should also emerge evidence for the mineral impact upon pH being linear or non-linear with respect to mineral ppm's (mg/L's). As it stands now, the Kolbach method is linear, and this also is validly questionable. Each mineral bump would require additional alkalinity whereby to maintain zero RA.

 

[cire]

I would initially suggest trying 75 ppm Ca++ and 15 ppm Mg++ (balanced with Alkalinity) for the respective zero RA waters. Then I would suggest a repeat of every test via bumping these to 150 ppm and 30 ppm respectfully, followed by another repeat via bumping them to 300 ppm and 60 ppm respectfully, as this should also emerge evidence for the mineral impact upon pH being linear or non-linear with respect to mineral ppm's (mg/L's). As it stands now, the Kolbach method is linear, and this also is validly questionable. Each mineral bump would require additional alkalinity whereby to maintain zero RA.

Some time past I conducted a series of mini mashes in expectation of disproving Kolbach's findings, but my first test confirmed those of Kolbach.

The test was simple and comparative, but cannot find my notes to give the exact details. A sample of my supply water and a base malt were used in equal proportions in two mashes done with a 5 minute stagger in a domestic oven at mash temperature. The quatities were probably 100 gm of malt and 250 ml of liquor and the pH measurement would have been of the wort, filtered and cooled to 20C. The supply water would typically have an alkalinity of 5 mEq/L with a calcium level of 4 mEq/l, but I do not have the actual figures. I would have reduced the alkalinity by about 1 mEq/L (probably slightly more) with a mineral acid for one mash and increased the calcium by salt addition by 3.5 times the alkalinity reduction, for the other. The resulting worts measured exactly the same pH using the same meter in a period of just 5 minutes.

I went on with further tests over a greater range that suggested such findings could not be extrapolated beyond a very limited range. Indeed it is obvious that my test although confirming what Kolbach claimed does have a very restricted practical range and probably less in the case by Kolbach with liquor of much lower mineral content.

You might wish to consider tring a similar test.

 

[Silver_Is_Money]

I have been graciously gifted the Barth and Zaman paper first mentioned in post #186 above. Some amazingly interesting things emerge from it, but I must seriously question their choice to sample at only 5 minutes into the mash for each of their multiples of mash pH tests. There is indeed a wealth of interesting information to be pondered within this paper, and I will list a couple of their "shocking" findings here:

1) They discovered that for the specific case of measuring at 5 minutes into a single infusion mash the Kolbach "3.5" divisor for Ca++ is actually (on average, and rounded) ~14.8 for Pilsner, ~7.2 for Pale Ale and ~12.2 for Munich malts respectively.

2) They discovered that the multiple point titration "curve" for their Pilsner malt was essentially linear to within 5% precision across a rather broad titration range, and not highly exponentially curved as for the Pilsner malt titration chart seen in post #108 above. They admit that they were quite surprised to find the buffering to be so linear.

If, as per Kolbach, the 3.5 divisor for calcium ions emerges post the boil (which is where he actually measured and thereby determined it, presumably for a German Pilsner malt as my guess), and at 5 minutes into the mash this divisor is a (minuscule as to its pH shifting impact) 14.8, then I speculate intuitively (while cautiously admitting that intuition generally leads to bad science) that the impact of calcium ions upon the downward shift of pH is gradual, and only minimally noticed at only 5 minutes into the mash. This leads me to wonder what the divisors value would be at 15 min., 30 min., 45 min., and 60 min. into the mash.

If we linearly regress Pilsner malts 14.8 divisor at 5 minutes and 3.5 divisor at 120 minutes (presuming here a typical 60 min. mash and 60 min. boil) the simple linear equation that evolves is:

Ca_Divisor_Value = -0.0982609(Time_Min) + 15.2913

Solving linearly for the Ca++ ions divisor value at a few evolving times within the brewing process thereby gives us:
5 min. = 14.8
15 min. ~= 13.8
30 min. ~= 12.3
45 min. ~= 10.9
60 min. ~= 9.4
120 min. = 3.5

Disclaimer: It is purely speculation that this phenomenon is linear with respect to time, and it far and away most likely is not.

 

[Big Monk]

I have been graciously gifted the Barth and Zaman paper first mentioned in post #186 above. Some amazingly interesting things emerge from it, but I must seriously question their choice to sample at only 5 minutes into the mash for each of their multiples of mash pH tests. There is indeed a wealth of interesting information to be pondered within this paper, and I will list a couple of their "shocking" findings here:

1) They discovered that for the specific case of measuring at 5 minutes into a single infusion mash the Kolbach "3.5" divisor for Ca++ is actually (on average, and rounded) ~14.8 for Pilsner, ~7.2 for Pale Ale and ~12.2 for Munich malts respectively.

2) They discovered that the multiple point titration "curve" for their Pilsner malt was essentially linear to within 5% precision across a rather broad titration range, and not highly exponentially curved as for the Pilsner malt titration chart seen in post #108 above. They admit that they were quite surprised to find the buffering to be so linear.

If, as per Kolbach, the 3.5 divisor for calcium ions emerges post the boil (which is where he actually measured and thereby determined it, presumably for a German Pilsner malt as my guess), and at 5 minutes into the mash this divisor is a (minuscule as to its pH shifting impact) 14.8, then I speculate intuitively (while cautiously admitting that intuition generally leads to bad science) that the impact of calcium ions upon the downward shift of pH is gradual, and only minimally noticed at only 5 minutes into the mash. This leads me to wonder what the divisors value would be at 15 min., 30 min., 45 min., and 60 min. into the mash.

If we linearly regress Pilsner malts 14.8 divisor at 5 minutes and 3.5 divisor at 120 minutes (presuming here a typical 60 min. mash and 60 min. boil) the simple linear equation that evolves is:

Ca_Divisor_Value = -0.0982609(Time_Min) + 15.2913

Solving linearly for the Ca++ ions divisor value at a few evolving times within the brewing process thereby gives us:
5 min. = 14.8
15 min. ~= 13.8
30 min. ~= 12.3
45 min. ~= 10.9
60 min. ~= 9.4
120 min. = 3.5

Disclaimer: It is purely speculation that this phenomenon is linear with respect to time, and it far and away most likely is not.

A few thoughts:

1.) I too am curious about the 5 minute measurement. Let's assume for a second that this paper represents a valid change in our thinking on the downward pH shift from Ca (they don't measure for the effect of Mg here but we can assume something comparable). Obviously, the larger the Ca content, the more drastic this drop in mineralization change is. Very curious findings and very interesting.

2.) Like I said in our PM, this should not be shocking (or "shocking" ). We can safely assume that the a2 and a3 titration values, if measured for most base malts, would be very small compared to their crystal, roast and Sauermalz counterparts. These values are really what sway the linear vs. polynomial characteristics of the malt.

With respect to the mineralization portion, I have what I think is a parallel in my industry (electric utility): Load Masking. Load masking is a phenomenon by which distribution feeder loading (residential, commercial, etc. customers) is "hidden" by the fact that we have a considerable amount of photovoltaic, wind, or waste gas generators on the circuit. It is important to us to "unmask" the "hidden" load in order to be able to do some of our important background calculations for transformer loading , etc.

What we may have here, particularly for batches produced with hefty source water calcium or added calcium, is a major overestimation of the downward pH shift from Ca (and assuming Mg, although we know the effect of Mg is much in general because of lower values in source water and lower additions of Mg salts). This could have the effect of "masking" other errors in a pH algorithm, especially is the modern denominators are much larger than derived by Kolbach.

 

[Silver_Is_Money]

One way to look at this (again rather broadly and purely speculatively and intuitively) is to witness that it is generally accepted that a drop in pH of 0.1 to 0.3 pH points is witnessed across the boil, and to witness generally the same magnitude of drop within the mash via moderate mineralization in the form of calcium ions, and to sum across them a midpoint as being the end of the mash, then by this loose and intuitive ballparking one can derive that roughly half of the Ca++ induced pH drop occurs within the mash, and roughly half occurs during the boil. And in doing this purely mental exercise one derives precisely that which AJ has told us, I.E, that only roughly half of the pH drop which Kolbach measured occurs within the mash. By this weak/intuitive approach to justifying AJ's observation, the "ballpark" Ca++ mEq divisor should be 7 as opposed to 3.5, and (by further inference) the Mg++ mEq divisor should be 14 instead of 7. And critically all mash pH measurement must be taken at the termination of the mash.

I fully agree that if the science as we have evolved it and as witnessed within our spreadsheet models matches closer to Kolbach than to AJ and now Barth and Zaman, then something "else" is deeply and fundamentally in error elsewhere within our simplistic math models which drive our software.

 

[Big Monk]

One way to look at this (again rather broadly and purely speculatively and intuitively) is to witness that it is generally accepted that a drop in pH of 0.1 to 0.3 pH points is witnessed across the boil, and to witness generally the same magnitude of drop within the mash via moderate mineralization in the form of calcium ions, and to sum across them a midpoint as being the end of the mash, then by this loose and intuitive ballparking one can derive that roughly half of the pH drop occurs within the mash, and half occurs during the boil. And in doing this purely mental exercise one derives precisely that which AJ has told us, I.E, that only roughly half of the pH drop which Kolbach measured occurs within the mash. By this weak/intuitive approach to justifying AJ's observation, the "ballpark" Ca++ mEq divisor should be 7 as opposed to 3.5, and (by further inference) the Mg++ mEq divisor should be 14 instead of 7. And critically all mash pH measurement must be taken at the termination of the mash.

Definitely adds another dimension to troubleshooting disparities between measured and predicted pH.

 

[Silver_Is_Money]

Further speculation:

No matter what we call it, whereby here we are calling it "Mash pH", what is always being measured is the emerging "Wort pH".

For far and away most beers a measure of acidity (typically in the form of the lactic acid on the surface of acid malt, lactic acid alone, or phosphoric acid) has been added to the mash liquor which is during the mash merely emerging (or evolving) into Wort. Since most people tend to grab "mash pH" samples at the mark of 10 to 15 minutes into the mash, it is likely that some portion of the measured acidity thereby seen by the pH meter is in the form of the added acid which has yet to have fully interacted with the embedded causticity of the grist. This would imply a false low pH reading correlating more inline with Kolbach purely by coincidence. We intuitively infer the "causation" of this lower measured mash pH reading thereby with Kolbach's formula constants being correct, even within the mash, and even at any time junction therein, yet we know implicitly (but utterly fail to apply) that correlation alone does not necessarily imply causation, as well as knowing that Kolbach did not measure pH drop due to Ca++ or Mg++ during the mash, but rather post boil. That Barth and Zaman did not witness this Kolbach correlating level of pH drop is potentially due to their not having acidified their samples mash water. They properly thereby pH measured only the 5 minute mark emergence of H+ ions due to exclusively the interaction of calcium ions upon malt phosphates, etc..., and not any H+ ions present due merely to intentional water acidification. With this assessment of mine in itself being yet more intuition...

The mash pH (Wort pH not fully emerged, as this occurs only post boil) is logically at its most evolved/emerged during the mash phase only at mash terminus. Thus the critical need to measure "mash pH" at mash terminus.

 

[Big Monk]

Thus the critical need to measure "mash pH" at mash terminus.

This is system dependent though. If you are constantly recirculating, you are likely to see not only a faster "locking in" of the pH (Mash pH = Wort pH), but also a steady pH across the entire mash.

So, as you like to say Larry, it depends!

 

[Silver_Is_Money]

So, as you like to say Larry, it depends!

Indeed!!! And as such, as we evolve our software to match our highly local reality, we often find that others are not always seeing very good agreement with it via using it within and measuring/comparing it with their own local reality. Whereby here "local reality" = "local system and also process related methodology". Thus the inevitable: "I find that so and so's software is superior to yours", or the generally more palpably agreeable and gratifying "I find that your software is superior to so and so's".

As such, it would be best if everyone had the tool (math model) outline whereby to make/tweak their own locally agreeing software, and thus this thread.

That it is often stated within peer reviewed brewing literature that small sample mashes generally do not scale well to the production level is merely more evidence for the above. In addition to their mash pH sample drawing time that has been brought into question, Barth and Zaman's measured reality at the small sample level may simply not yield the same revised Kolbach constant valuations by malt at a different scale, or for any process other than single infusion at their chosen mash infusion temperature, etc...

 

[ScrewyBrewer]

I stumble across some of AJ's 2005 work today while visiting the ResearchGate site... Alkalinity, Hardness, Residual Alkalinity and Malt Phosphate: Factors in the Establishment of Mash pH

The ResearchGate site seems to be a really good resource, my thanks to the OP who shared it.

 

[Silver_Is_Money]

I stumble across some of AJ's 2005 work today while visiting the ResearchGate site... Alkalinity, Hardness, Residual Alkalinity and Malt Phosphate: Factors in the Establishment of Mash pH

The ResearchGate site seems to be a really good resource, my thanks to the OP who shared it.

What is their asking price to release this document?

 

[Big Monk]

What is their asking price to release this document?

I have it Larry. I have all A.J.'s documents and papers.

 

[Silver_Is_Money]

On June 28, 2017 AJ deLange stated this on this very Brewing Science forum:

I have not done any formal experimental evaluations of the shift in part because I know that the considerations mentioned above would mean that such a project would be no mean undertaking. If Kolbach couldn't do it I don't see how I could. I have, therefore, cleaved to the 3.5 mEq of calcium number and use that as the basis for all calculations. I think I have good estimates of malt buffering capacities so that part of my protocol is fairly robust but I am well aware that the actual number I would encounter with any real grist will not be 3.5 but only near it.

This seemingly conflicts with times on this forum when he has stated that the factor is likely closer to 7 as opposed to 3.5.

Here is the link: Question about differences in calculated Mash pH shift due to mineralization

The question thus becomes: If AJ himself openly admits to never having tested whereby to confirm or deny Kolbach, what if any credence should be placed upon any of his papers or statements with regard to it?