Bru'n water pH puzzle

Second AG brew last weekend, so forgive me if this is a newbie question...

Bru'n water overestimated the amount of Lactic Acid I needed to bring my mash pH down to 5.2.

I took careful notes during the mash, and now I've gone back in and double checked everything, and I come up with the same results, so all really obvious gaffs eliminated. All measurements taken by removing a small mash sample, cooling to room temp, and using a calibrated (that morning) Hanna pHep 5 meter.

I fine tuned the vols and grains in the spreadsheet and I've input all my water salts (minimal). The spreadsheet is still telling me to add 4.8mL of lactic acid, but when I did that during the mash, I got a pH of 4.98.

I expected it to be within a few hundredths of 5.2. Any ideas? (pdf of worksheets att'd since xls not allowed). The only thing I could come up with is that I had pretreated the water with 1 campden tab per 6 gallons and maybe that had an effect (?)

For extra credit, I adjusted pH back to 5.23 by adding 1g of slaked lime (lucky guess on the amount), would you have done the same or different?

View attachment Brun Water v1_16bus-PDM-mashPh-problem-20131013-1.pdf

I would guess since you have a fair amount of roasted grains the degree of roast could make a difference? I know that LHBS sometimes cautions me if they are on top of it to ease back on a particular roast if it is either too light or too dark than normal. Martin could be of more help, he wrote it I believe.

Also, if your water is fairly soft, pH can flucuate much easier than with a water with more carbonate (alkalinity)

To estimate mash pH is a fairly simple matter. You compute the proton deficit of your water at the desired mash pH. You do the same for the base malt and any specialty malts that have a proton deficit at the desired pH. You compute the proton surfeit of any specialty malts that have a proton surfeit at the target pH. You add up all the deficits and subtract all the surfeits and, unless your beer has lots of dark malt, there will be a deficit which is made up by adding lactic acid. As the properties of lactic acid are well known it is easy to determine how much to add to balance a particular deficit. It is also easy to determine the deficit of water of known alkalinity. This is where 'easy' ends. It is not easy to determine the proton deficits or surfeits of malt without making an elaborate set of measurements on each and this means each of the malts you are actually using. If you don't do that then you can only estimate what the deficits or surfeits might be at a particular pH based on the malts' colors or measurements done by someone else. There are some of these abroad but they were not done rigorously so the data is approximate. As such you can only get an approximate estimate of the amount of acid needed. The smart camper uses the spread sheeet or calculator as a guide and adds the acid in increments checking pH as he goes. Better yet, he makes a test mash, determines how much acid it takes to get that to proper pH and then scales the answer to the size of the full mash.

Slaked lime is fine for mash pH adjustment but it may take more than you calculate because some of the calcium reacts with malt phosphate thus releasing acid which neutralizes some of the lime's alkalinity. This doesn't matter as the calcium is precipitated and the neutralized alkalinity is only water.

I live fairly near the OP. My water's chemistry is quite variable. Do you get your water from SNEW? Did you have it tested yourself? You can probably get a more complete report from your municipality, which would be good to compare to your test results. I had two tests on my water and they're not even close. I think the only way to be sure of what's in your water on any given day is to start from RO or DI water and add minerals from there.

I like to shoot for 5.4 in the middle rather than 5.2 or 5.6 on the edges of the zone.

I generally put Rye Malt in as a base malt, which change the acidity in the mash calculation. If that was a roasted malt, then add it such. It may also be why you chose to use Chalk to add alkalinity to raise the predicted mash pH.

It seems like the whole 4 ml addition of lactic acid was not necessary, and would likely have gotten you close to 5.3 without the lime addition. I am jealous of your brewing water... I have to use R/O.

ajdelange said:

To estimate mash pH is a fairly simple matter. You compute the proton deficit of your water at the desired mash pH. You do the same for the base malt and any specialty malts that have a proton deficit at the desired pH. You compute the proton surfeit of any specialty malts that have a proton surfeit at the target pH. You add up all the deficits and subtract all the surfeits and, unless your beer has lots of dark malt, there will be a deficit which is made up by adding lactic acid. As the properties of lactic acid are well known it is easy to determine how much to add to balance a particular deficit. It is also easy to determine the deficit of water of known alkalinity. This is where 'easy' ends. It is not easy to determine the proton deficits or surfeits of malt without making an elaborate set of measurements on each and this means each of the malts you are actually using. If you don't do that then you can only estimate what the deficits or surfeits might be at a particular pH based on the malts' colors or measurements done by someone else. There are some of these abroad but they were not done rigorously so the data is approximate. As such you can only get an approximate estimate of the amount of acid needed. The smart camper uses the spread sheeet or calculator as a guide and adds the acid in increments checking pH as he goes. Better yet, he makes a test mash, determines how much acid it takes to get that to proper pH and then scales the answer to the size of the full mash.

Slaked lime is fine for mash pH adjustment but it may take more than you calculate because some of the calcium reacts with malt phosphate thus releasing acid which neutralizes some of the lime's alkalinity. This doesn't matter as the calcium is precipitated and the neutralized alkalinity is only water.

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Okay, AJ, so then bottom line, what you're saying is that I shouldn't expect Bru'n Water to be very accurate, I should use it as an initial indication and incrementally add lactic acid to zero in on my desired pH. Do I have that right?

If so, I can live with that.

mchrispen said:

I like to shoot for 5.4 in the middle rather than 5.2 or 5.6 on the edges of the zone.

I generally put Rye Malt in as a base malt, which change the acidity in the mash calculation. If that was a roasted malt, then add it such. It may also be why you chose to use Chalk to add alkalinity to raise the predicted mash pH.

It seems like the whole 4 ml addition of lactic acid was not necessary, and would likely have gotten you close to 5.3 without the lime addition. I am jealous of your brewing water... I have to use R/O.

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Matt:

Yeah, for the most part, I like my water too. The only caveat is that because it's city water, the source can vary with the seasons. So far, I've based all my water chemistry on a single Wards report done last summer. I may pull another one soon just to have a baseline.

My water salting routine is pretty minimal, but I do believe that in most cases I will need a little acid addition to get pH down to the middle of the zone. I guess shooting for the middle is a good idea until I get a particular recipe dialed-in.

Whether a malt is a base, crystal, or roasted is still a bit of a mystery to me. I've been inputting anything that says "Caramel" or "Crystal" in the product write-up as Crystal. Is that right? I wouldn't have thought to put "Base Malt" for anything but 2-Row.

satph said:

I live fairly near the OP. My water's chemistry is quite variable. Do you get your water from SNEW? Did you have it tested yourself? You can probably get a more complete report from your municipality, which would be good to compare to your test results. I had two tests on my water and they're not even close. I think the only way to be sure of what's in your water on any given day is to start from RO or DI water and add minerals from there.

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Hay Satph - Yes, we are in the 2nd district and get our water from SNEW, and yes, I sent a sample to Ward to test it for me over the summer (water report att'd - hope this helps). Caveat - I use an Everpure 300 water filter to improve the taste of my drinking water, and I use that water for brewing. I believe this is mostly the difference between the muni water report and Ward's.

As for what I said above about a city water source quality varying during the year, and given ours is largely from reservoirs, have you seen this timely little item on the home page of the SNEW web site? Just noticed it now:


Seriously?? Clearly these people are not brewers or they wouldn't be chattering about something so meaningless as fine whites!!!

View attachment 28Wilson-Water1.pdf

satph said:

I live fairly near the OP. My water's chemistry is quite variable. Do you get your water from SNEW? Did you have it tested yourself? You can probably get a more complete report from your municipality, which would be good to compare to your test results. I had two tests on my water and they're not even close. I think the only way to be sure of what's in your water on any given day is to start from RO or DI water and add minerals from there.

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Hey, Satph:

Can you PM me or post a copy of the water reports you had done?

Thx!

It sounds like everyone has a bit of the puzzle figured out here. If you have a stable water source, you may be fine with simply brewing a few times, tweaking the expected pH to get a good prediction, and then use that as a standard from then on.

If your water changes over time, and a lot of places do, then you probably really want to test the water or pH each time you brew in order to get an accurate calculation.

Frankly, I haven't had my water checked in a few years. I have begun to wonder if it's time to do it again, and maybe more often from now on. I know our water doesn't change a LOT over time, but could change some over a lot of time.

philipmeese said:

Okay, AJ, so then bottom line, what you're saying is that I shouldn't expect Bru'n Water to be very accurate,

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Depends on what you mean by 'accurate' but I will stand by my recommendation that it be used as a guideline with checks or by incremental additions.

philipmeese said:

I should use it as an initial indication and incrementally add lactic acid to zero in on my desired pH. Do I have that right?

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Yes and the remark applies to all the other spreadsheets/calculators out there as well. It isn't that the models are bad (though most of them assume that buffering capacity is constant with pH) so much as it is that it would be impossible for them to have data on the particular lot number of a particular malt from a particular maltster who bought the barley from a particular farmer.

Hi Philip,

Your mileage may vary. Take the comments below with a grain of salt - I am still learning.

AJ's clarification is spot on, not that he needs my validation. He is an expert, I am not. I do believe the spreadsheet is a valuable brewing and educational tool, and has helped me tremendously.

On brewday, it makes sense to measure pH after/during your salt additions, and then adjust using acid or base as required during dough in. This really helps to address variability of your source water. Because I have spent invested in a R/O system, I have been spending a lot of focus and care in measurement. I measure the pH and volumes of my strike and sparge water separately as they will be treated differently (I do not dump everything into the HLT). I then add the salts (dough in) to the mash and measure the change in pH. With my RIMS system, I find the change occurs rapidly at from mixing with the malts. I will make an additional measurement(s) to verify that things have stabilized after about 5 minutes. I will adjust then with acid/base only if required. I have found this process very well aligned to Bru'n water's predictions, although 5 minutes in may be too late for the adjustment. I toss the rest of the salt additions into the sparge water and then measure pH to ensure it is somewhere close or below 6.0 pH. If needed, I add acid 1 ml at a time until I hit the target.

Another complication maybe your use of chalk, which is very difficult to dissolve and quickly impact the mash pH. Theoretically the chalk and the lactic acid will counter each other - so not sure about the net result there. I have moved chalk completely out of my brew house and replaced it with pickling lime. Baking soda adds sodium, which I avoid, but is part of your target ideal water profile.

In using the spreadsheet, I focus almost exclusively on acid additions for calcium and sulfate choices, and not on alkaline. Of course, with roasted and crystal grains, I will most likely need pickling lime to adjust the estimated mash pH, and will rebalance the acids to achieve sulfate and calcium needs and my target mash pH and minimize additions.

On the mash acidification worksheet, I only choose ROAST or CRYSTAL when I specifically know it is such, or see a dark Lovibond rating (darker than 8-10 L). All else I treat as BASE malt, even un-malted grain or flakes. This could be completely wrong - happy to be corrected - but again is has worked as expected on my brew days.

Your PDF showed a 20 ounce Rye Malt addition, 3 L, that yielded 0.2 mEq/L acidity. If treated as Base Malt, it would add half that total acidity into the equation. Also, I want to make sure that you intend a 7.36 gallon post boil volume? Not sure that makes a lot of difference here, but does change the beer color calculation slightly.

I will have a go at putting your target and recipe information into the spreadsheet and PM you the results.

ajdelange said:

. The smart camper uses the spread sheeet or calculator as a guide and adds the acid in increments checking pH as he goes.

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Quick question AJ:

I'm almost sure I remember you writing (maybe it was in the primer thread) that it takes something like 15 minutes for the mash pH to stabilize before you can take a reading that is worth anything - and at that point it's too late to adjust the pH and have it make a difference. So I recall that the advice was basically to take the reading to know what adjustments to make next time.

Am I remembering that right?

If so, how would you "check pH as you go"? Obviously the test mash would fix that but that isn't on the fly.

This is, at the moment, academic as I don't have a meter. But it is something that's on my list.

Thanks

Philip, sorry for your troubles. However if your water supply is subject to change, then it would be impossible to have any program predict pH accurately. Garbage In = Garbage Out.

Colin Kaminsky has had to deal with variable water quality from his water supplier for years. He tests hardness and alkalinity prior to each brew to assess the current quality. He alters his water treatment based on that result. You would be wise to include that sort of 'spot' testing too. The main culprit in unexpected mash pH response is alkalinity. At a minimum, I would obtain an alkalinity test kit so that you would have the ability to monitor that piece of the puzzle.

ResumeMan said:

I'm almost sure I remember you writing (maybe it was in the primer thread) that it takes something like 15 minutes for the mash pH to stabilize before you can take a reading that is worth anything - and at that point it's too late to adjust the pH and have it make a difference. So I recall that the advice was basically to take the reading to know what adjustments to make next time.

Am I remembering that right?

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Yes and that is fine if your mash pH comes in somewhere between 5.2 and 5.6 but if it comes in at 5 or 6 you should probably try to do something about it. It may take you 15 minutes to have a good idea as to what the mash pH would settle in at eventually (most of the change takes place early on and you can guess reasonably well where it will finally come to rest and it may take another 15 minutes before you see the fruits of any correction you try. You may overshoot. or you may overshoot again requiring a second correction so it could be 45 minutes to an hour before you get the pH right. I 'll bet lots of readers (and the writer) have spent an unpleasant afternoon or evening chasing pH. Experience helps a lot and I think that you'll have to accept that you are going to miss a couple of times before you start hitting it right consistently. Even if it takes an hour, enzymes are not going to be denatured by the range of pH into which you might take them (unless you used 10N acid when you thought you were using N acid). But heat is working against them so that it is clear that you won't get the beer you would have had you gone straight to the correct pH but I'm guessing that you'll get better beer than if you don't correct. Remember that once the mash pH is correct you can expect pH to track pretty well throughout the rest of the process.

ResumeMan said:

If so, how would you "check pH as you go"? Obviously the test mash would fix that but that isn't on the fly.

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I really favor a test mash especially for the beginner. Keep in mind that an actual mash is a test mash too. This brings us back to the make a note and correct next time if you are within reason based on an particular addition approach.

Keep in mind that a spreadsheet or calculator can be used to advantage to calculate a trial acid addition for a test mash. Also keep in mind that if a test mash comes in high with a given addition incrementing the amount of acid and then retesting on a new test mash will probably give a better result than trying to correct the original test mash on the fly.

mabrungard said:

Philip, sorry for your troubles. However if your water supply is subject to change, then it would be impossible to have any program predict pH accurately. Garbage In = Garbage Out.

Colin Kaminsky has had to deal with variable water quality from his water supplier for years. He tests hardness and alkalinity prior to each brew to assess the current quality. He alters his water treatment based on that result. You would be wise to include that sort of 'spot' testing too. The main culprit in unexpected mash pH response is alkalinity. At a minimum, I would obtain an alkalinity test kit so that you would have the ability to monitor that piece of the puzzle.

Click to expand...

Martin: Thanks for the reply.

Woe to the brewer who is subject to municipal supply. When it's good, it's pretty good, but the variability is killing me!

I'll look into the alkalinity test kit as a short term solution, and longer term I may go to RO to reduce the variation completely.

Are there specific water test kits you would recommend?

I've always used Hach which isn't to say that some of the other manufacturer's kits aren't good. But you do get what you pay for and Hach stuff isn't as cheap as some of the alternatives. Alkalinity is actually the easiest of water parameters to measure. You can even put a test kit together yourself. See http://wetnewf.org/pdfs/measuring-alkalinity.html. Even if you don't want to put the stuff together scan over the whole thing and check out the 'digital buret' illustrated in the last picture. These make tests accurate, simple, repeatable and can be used for hardness, alkalinity, chloride and other ions (but not, unfortunately, sulfate, sodium or potassium).

The cheap and dirty approach is drop count kits available from pool suppliers, pet stores and hardware stores.

Would test for alkalinity and hardness be enough to use the bru'n spreadsheet? I have a water report from ward but my water changes by the season. Could I estimate the water additions with just the alkalinity and the hardness? I have a ph meter on the way.

ajdelange said:

To estimate mash pH is a fairly simple matter. You compute the proton deficit of your water at the desired mash pH. You do the same for the base malt and any specialty malts that have a proton deficit at the desired pH. You compute the proton surfeit of any specialty malts that have a proton surfeit at the target pH. You add up all the deficits and subtract all the surfeits and, unless your beer has lots of dark malt, there will be a deficit which is made up by adding lactic acid. As the properties of lactic acid are well known it is easy to determine how much to add to balance a particular deficit. It is also easy to determine the deficit of water of known alkalinity. This is where 'easy' ends. It is not easy to determine the proton deficits or surfeits of malt without making an elaborate set of measurements on each and this means each of the malts you are actually using. If you don't do that then you can only estimate what the deficits or surfeits might be at a particular pH based on the malts' colors or measurements done by someone else. There are some of these abroad but they were not done rigorously so the data is approximate. As such you can only get an approximate estimate of the amount of acid needed. The smart camper uses the spread sheeet or calculator as a guide and adds the acid in increments checking pH as he goes. Better yet, he makes a test mash, determines how much acid it takes to get that to proper pH and then scales the answer to the size of the full mash.

Slaked lime is fine for mash pH adjustment but it may take more than you calculate because some of the calcium reacts with malt phosphate thus releasing acid which neutralizes some of the lime's alkalinity. This doesn't matter as the calcium is precipitated and the neutralized alkalinity is only water.

Click to expand...

^^^^what he said even thou i dont understand a thing he said

thedude123 said:

Would test for alkalinity and hardness be enough to use the bru'n spreadsheet? I have a water report from ward but my water changes by the season. Could I estimate the water additions with just the alkalinity and the hardness? I have a ph meter on the way.

Click to expand...

It would be enough for you to estimate pH and for you to see the effects of calcium salt and acid or base additions to the mash. Clearly it would not be enough for you to set sulfate and chloride to a particular level.

thedude123 said:

I have a water report from ward but my water changes by the season.

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I have the same problem. My water source is a river ten blocks away from my house which makes it impossible to maintain any consistency in flavor. I choose to go with RO water and so far it seems to have made a big difference in my brewing.

Glynn said:

^^^^what he said even thou i dont understand a thing he said

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Proton deficit and surfeit are (I believe) new ways of looking at the acid base chemistry which determines mash pH. I'm trying to introduce these to the brewing community in the hopes that this approach will make this subject easier to understand. Only the earliest thoughts on this made it into the Palmer/Kaminski book and I've had some time to think more about this since the publishing deadline for that. You can see the slides I used in a presentation to MBAA District Mid Atlantic yesterday at http://wetnewf.org/pdfs/Brewing_articles/MBAA_FREDERIC.pptx

The methodology that AJ mentions is how Bru'n Water calculates mash pH. You can't use distilled water pH values and expect to be able to calculate a resultant pH.

ajdelange said:

Proton deficit and surfeit are (I believe) new ways of looking at the acid base chemistry which determines mash pH.

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I should say 'new for brewers'. Water chemists have used 'proton condition' for a long time.

ajdelange said:

It would be enough for you to estimate pH and for you to see the effects of calcium salt and acid or base additions to the mash. Clearly it would not be enough for you to set sulfate and chloride to a particular level.

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That is really my problem. As far as flavor profile of the water the things I care most about is the sulfate and chloride. Is there a way to test these levels the same as I am testing for GH/KH?

mabrungard said:

The methodology that AJ mentions is how Bru'n Water calculates mash pH. You can't use distilled water pH values and expect to be able to calculate a resultant pH.

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I really like the spreadsheet you came up with but since my water changes seasonally, I really can't fill in all the needed fields for the make up of the water.

thedude123 said:

That is really my problem. As far as flavor profile of the water the things I care most about is the sulfate and chloride. Is there a way to test these levels the same as I am testing for GH/KH?

Click to expand...

Yes, at least for the chloride. If you have a look at http://www.wetnewf.org/pdfs/measuring-alkalinity.html you will learn the basic concept for measuring alkalinity: titration of a sample with and acid until and indicator changes color. One can do titrations for many other parameters such as hardness and chloride but not for sulfate (I'll come back to that). With hardness the titrant is EDTA, for chloride it is a mercury salt. I direct your attention to the bottom of the wetnewf page where a 'digital titrator' is illustrated. These come with pre mixed titrant cartridges and use very little of the liquid within for a single test which is comforting when contemplating disposal of the residue from the chloride test.

There is no titration test for sulfate but there are tests in which barium chloride is added to a sample. This causes a white precipitate to form and the turbidity of the solution depends on the amount of sulfate in the water. There are clever ways of measuring this turbidity and a sulfate estimate can, therefore, be derived.

For less than the $ required to obtain testing equipment and chemicals to measure hardness, alkalinity, sulfate and chloride you can buy an RO sytem which removes all of the above to the point that you don't have to worry about variations because there isn't any.

ajdelange said:

Yes, at least for the chloride. If you have a look at http://www.wetnewf.org/pdfs/measuring-alkalinity.html you will learn the basic concept for measuring alkalinity: titration of a sample with and acid until and indicator changes color. One can do titrations for many other parameters such as hardness and chloride but not for sulfate (I'll come back to that). With hardness the titrant is EDTA, for chloride it is a mercury salt. I direct your attention to the bottom of the wetnewf page where a 'digital titrator' is illustrated. These come with pre mixed titrant cartridges and use very little of the liquid within for a single test which is comforting when contemplating disposal of the residue from the chloride test.

There is no titration test for sulfate but there are tests in which barium chloride is added to a sample. This causes a white precipitate to form and the turbidity of the solution depends on the amount of sulfate in the water. There are clever ways of measuring this turbidity and a sulfate estimate can, therefore, be derived.

For less than the $ required to obtain testing equipment and chemicals to measure hardness, alkalinity, sulfate and chloride you can buy an RO sytem which removes all of the above to the point that you don't have to worry about variations because there isn't any.

Click to expand...

I am beginning to think that RO water is the best way to go if you do not have a consistent water source. Thank you for the information.

If you have a convenient source of RO water it definitely makes life easier if less challenging (you don't learn as much tailoring RO to your needs as you will if you work with your source water).

I am going to look into an RO system. I don't want to go to the store to buy water each time I brew.