Predict pre-boil pH in Bru'n Water?

[J.Miller]

Hello,
Is there a work around in Bru'n Water to predict pre-boil pH (post-mash and sparge pH)?
Thanks,
Jeff

 

[jdauria]

Don't believe so, however, recently read somewhere, forget where it was, that pH changes about 0.2 points from mash pH to end of mash. Then 0.3 by end of boil, and 0.5 by end of fermentation. So if you take your mash pH, you can estimate where it should be post mash. Do you acidify sparge water to about 5.5? Just FYI, that article went on and said finished beer pH should be between 4.0-4.6, lagers around 4.5 and pale beers between 4.0-4.3.

 

[Silver_Is_Money]

For 'Mash Made Easy' the steps required are rather straight forward. Much of the process revolves around remembering that the 'Kolbach Ca++ and Mg++ pH Shift Multiplier' is to be set to 0.50 for best predicting Mash pH adjustment, and to 1.00 for best predicting 'Knockout '(post boil and cooling) pH adjustment.

Initially you have two choices to contemplate:
Choice #1) Do I want to make only a single pH adjustment with about 5-10 minutes remaining in the boil whereby to hit a desired 'Knockout' pH? (or)
Choice #2) Do I want to make two separate pH adjustments, with the first targeting a desired target 'Mash' pH, and the second targeting a desired 'Knockout' pH?

Steps required for Choice #1:
1) Set the 'Kolbach Ca++ and Mg++ pH Shift Multiplier' cell to 1.00, which is 'Knockout pH prediction Mode'.
2) Set the 'Desired Target Knockout (Post Boil and Cooling)' calculator cell to your desired post boil and cooling pH. 5.15 is rather common here.
3) Below this cell you will now see the computed target Mash pH that must be manually entered into the 'Desired Target Mash pH @ 68 F. =' cell. For the case of targeting Knockout at 5.15 pH this value will be 5.24 as your Mash pH target entry value.
4) Make the computed single Acid adjustment when only about 5-10 minutes remain in the boil step. (this method completely skips any effort to regulate Mash pH)

Steps required for Choice #2:
1) Follow all of the steps as seen above for "Choice #1" and record the computed Acid adjustment.
2) Next, set the 'Kolbach Ca++ and Mg++ pH Shift Multiplier' cell to 0.50, which is 'Mash pH prediction Mode'.
3) Set the 'Desired Target Mash pH @ 68 F. =' cell to your desired Mash pH target. 5.40 - 5.50 is rather common here.
3) Record and also make the computed 'Mash pH' Acid or Base adjustment seen in step 3 above either pre or very early on during the mash step.
5) Subtract the adjustment value derived in step #3 from the recorded adjustment value derived in step #1.
6) Make the second Acid adjustment computed via the subtraction carried out in step #5 above when only about 5-10 minutes remain in the boil step.

And then lastly, there is yet a third choice available within MME, whereby to use the 'Kettle pH' tab/sheet calculator by which to compute a separate Knockout pH adjustment. You can use this feature even if you have used a spreadsheet other than MME to compute a Mash pH adjustment.

 

[J.Miller]

jdauria, I am curious as to why you asked if I adjust sparge water to 5.5. Yes I have on my last batch, a hefeweizen.

Yeah, it appears there is no Bru'nWater workaround - wondering if anybody has tinkered. The article you mentioned, I have read it too, and I believe it is a good guideline. I have also begun taking pH of commercial beers, and found agreement.

 

[J.Miller]

Larry, thanks much for your reply. I downloaded your MME v 11.0 last night. I have not used it, and not any of the previous versions. I will now, since you provided some instructions.

Are there other instructions for its use? I was unable to find them. but I admit I was unable to spend time to comprehend the operation of it and figure it out myself.

 

[Silver_Is_Money]

Larry, thanks much for your reply. I downloaded your MME v 11.0 last night. I have not used it, and not any of the previous versions. I will now, since you provided some instructions.

Are there other instructions for its use? I was unable to find them. but I admit I was unable to spend time to comprehend the operation of it and figure it out myself.

I've never written down any instructions because I've felt it was easy enough to use without them. But this is a special case that requires some simple instructions.

 

[J.Miller]

Larry,
As easy as your spreadsheet name implies, now that I spent time entering data from a completed batch I brewed recently, that used another water calculator.
Several questions, though.
1) Entering my batch data and results, a sample of 170° F post-mash and sparge wort cooled to 68-70° was at 5.66pH, verses the MME 5.75pH prediction, using a fresh-calibrated Apera pH60. Does the "DI mash pH manual override", "Buffering coefficient manual override", or the "Kohlbach ... shift multiplier" inputs affect this? CaCl2 only was added to this batch, and I selected 100% anhydride to match the other calculator ppm. The other calculator had a 5.47pH prediction.
2) Can I make my CaCl2 solid mineral form into a liquid form, and how? Will the liquid composition be stable?
Thanks,
Jeff

 

[Silver_Is_Money]

Larry,
As easy as your spreadsheet name implies, now that I spent time entering data from a completed batch I brewed recently, that used another water calculator.
Several questions, though.
1) Entering my batch data and results, a sample of 170° F post-mash and sparge wort cooled to 68-70° was at 5.66pH, verses the MME 5.75pH prediction, using a fresh-calibrated Apera pH60. Does the "DI mash pH manual override", "Buffering coefficient manual override", or the "Kohlbach ... shift multiplier" inputs affect this? CaCl2 only was added to this batch, and I selected 100% anhydride to match the other calculator ppm. The other calculator had a 5.47pH prediction.
2) Can I make my CaCl2 solid mineral form into a liquid form, and how? Will the liquid composition be stable?
Thanks,
Jeff

MME was within 0.1 pH points as to its Mash pH prediction. That seems to be within acceptable predictive norms. For that matter, even the competitor at a prediction of 5.47 pH was within acceptable prediction norms, despite missing by 0.19 pH points. If MME was to continue to be ~0.1 pH to the high side over hundreds of individual different recipes and process procedures I might begin to become concerned as to tweaking some internal parameters whereby to compensate. What sort of precision were you hoping for, given that this is merely a 1 batch (one data point) sample size.

As to your query:

Does the "DI mash pH manual override", "Buffering coefficient manual override", or the "Kohlbach ... shift multiplier" inputs affect this?

The answer is 'yes' to all of these, but the very same logic as above applies. It would be highly irrational to chase changes (both for me and for you) based upon a single data point.

That said, if you know the 68 degree F. post Mash and pre-boil pH to be 5.66, then enter 5.66 as the pH within the 'Kettle pH' module.

 

[Silver_Is_Money]

A liquid solution of CaCl2 is subject to evaporation, as well as to the settling out (dropping out) of any potential contaminating Ca(OH)2 content as CaCO3 due to air exposure during use (which seems to be common due to the low purity quality of available CaCl2), but would be far more reliably predictable overall as to its actual CaCl2 content.

 

[Silver_Is_Money]

A solution of CaCl2 in water should be pH neutral. If it measures on the basic side of neutral this is a clear indicator of extant Ca(OH)2 contamination, and poor manufacturing quality.

2HCl + Ca(OH)2 → CaCl2 + 2H2O is the likely manufacturing process for CaCl2.

 

[Silver_Is_Money]

After only a single batch (complete with Mash pH predictive accuracy to within 0.09 pH points) it is far too early to begin contemplating the tweaking of MME's many end user tweakable parameters.

 

[Silver_Is_Money]

The above stated, the one parameter which everyone should manually adjust is the 'Actual Grist Buffer Multiplier' value, as assisted via the use of 'Mill Gap Suggested Grist Buffer Multiplier' calculators output for your actual mill gap crush.

 

[Silver_Is_Money]

As to a suggestion regarding how to make a CaCl2 solution, I must warn that adding CaCl2 to water evolves an appreciable amount of heat, such that a Pyrex (or a Pyrex equivalent) measuring vessel (I prefer a 1 Liter Erlenmeyer Flask) is to be used along with a Pyrex stirring rod.

I suggest adding 100 grams of CaCl2 prills to about 850 mL of deionized or distilled (or exceptionally good RO) water initially, with stirring until dissolved. Allow to cool to room temperature and then carefully 'make up' the final volume to 1,000 mL ( 1 Liter) and stir again whereby to unify the solution. In a perfect world with 100% pure (Anhydrous) CaCl2 the resulting specific gravity (S.G.) of your solution made in this way will be 1.081. Anything lower than 1.081 SG is an indicator of how impure your CaCl2 was initially, with absorbed water being the main culprit here.

 

[Silver_Is_Money]

My spreadsheet calculator to assist you in making and then using a solution of CaCl2 can be found at this link:

https://www.homebrewtalk.com/thread...chloride-wt-vol-solutions.688308/post-9033212
Complements go to AJ deLange for providing the core formula used within this spreadsheet.

Note: Online spreadsheets such as 'Google Sheets' and the like really do an injustice to most all of my spreadsheets, corrupting them horribly. Therefore, please download and run in either LibreOffice Calc, or Excel.

 

[J.Miller]

Larry,
All great advice, thanks. For now, I'll not do a liquid solution of CaCl2, maybe in future. I understand now about the accuracy of pH prediction, and within 0.1 pH points being acceptable. I was unaware of this before. On my part, I was not trying to be critical, rather I was seeking to learn. Accept my apology, please, and thanks for your time spent on me.
Jeff

 

[Silver_Is_Money]

Lastly, taking Mash pH samples for cooling to room temperature and pH reading too early into the Mash generally results in receiving a false low pH reading. Quite logically, if you want to know the pH that your Mash "actually" accomplished, and you did a 60 minute Mash, the very best time to take your pH sample (and Mash pH reading) is at 60 minutes into the Mash. Don't sample early when the Mash water has not yet even saturated the inner-most regions of the last of the crushed grist kernels and reactions that impact pH (as well as saccharification) are as of yet incomplete and still ongoing. If you feel that you must assess Mash pH early for some strange reason, yet your desire is for accuracy (as it should be), my preference would be to do so at no sooner than the 40-45 minute mark of the Mash. Some say 30 minutes into the mash is OK, but I'm not fully convinced of this. Earlier is simply asking for a false low pH reading. It may speculatively even be the case that some software has been tweaked to favor somewhat lower pH prediction result output, while betting that a majority of users will have sampled too early, and/or that most like to mildly stir or swirl the pH probe in the sample while taking a pH reading, which leads to a false low pH due to "stirring error".

As to additional Mash pH taking advice regarding false low pH due to "stirring error", see this link:
https://www.homebrewtalk.com/threads/ph-measurements-whats-your-routine.695756/post-9172955