Advanced Water Chemistry Calculator Wildly Inaccurate For Acid Additions

DulcetBrewCo

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As the wordy title says the advanced water chemistry calculator is currently wildly inaccurate with its acid addition suggestions, a few weeks ago this nearly caused me to lose hours of work on a pilot batch had I not thought the numbers seemed off and done a mini-mash first to check. The calculator had me add around twice the acid actually required.

Guys, please can you sort this out? I'm paying for functionality here that is at best unhelpful and at worst will ruin people's batches. If you want to cross-reference then I suggest you use the free BrunWater calculator, which is extremely accurate.
 
Are you sure it's the calculator? I hit my numbers pretty consistently.
 
I think it's ok if you only need to make small adjustments or adjustments with salts only, but the calculated acid additions when you want to deliberately target an unusually low mash pH (say a pH of 5 for a crisp pilsner when your base water alkalinity is around 150ppm as CaCO3) end up way off.
 
I think it's ok if you only need to make small adjustments or adjustments with salts only, but the calculated acid additions when you want to deliberately target an unusually low mash pH (say a pH of 5 for a crisp pilsner when your base water alkalinity is around 150ppm as CaCO3) end up way off.
My base water is in the 70 ppm range. I do acid additions, lactic acid, to nearly all of my brews, both in the mash and in the sparge. I also use salts and as mentioned above, get consistently good results. Hence my question: Are you sure your variance is coming from the calculator? Have you tried other calculators such as Bru'n Water or to do the calculations by hand? I'm curious because of all the complaints I've seen about the site recently, results of the water calculator haven't topped the list.
 
I use Bru'n Water to compare, since I know that works consistently for me even if I target slightly unusual mash pH ranges (for which I have my reasons). I was hoping to only use Brewers Friend from now on, but unfortunately it just doesn't work, at least not in the cases I have looked at.

Take for instance a model mash as follows:

Water:

10L total treated mash liquor with profile:

Calcium 72ppm
Magnesium 9ppm
Sodium 32ppm
Chloride 31ppm
Sulphate 66ppm
Alkalinity 159ppm as CaCO3
pH 7.59

Grist:

3kg of 3 Lovibond base grain.

If I then set the Brewers Friend Advanced Water Chemistry Calculator to add only acid to the mash to target as pH of 5 it suggests 6.28ml of 80% Phosphoric acid.

However, the exact same calculation in Bru'n Water suggests adding only 4.3ml acid.

This is a wildly different amount of acid for such a small and basic mash, and indeed the predicted pH from Bru'n Water if I add 6.28ml is a 4.5, which is enormously off the intended pH of 5.

I can speak from experience and say that the Bru'n Water estimate is far, far closer to what happens in reality than is the Brewers Friend calculator.
 
I use Bru'n Water to compare, since I know that works consistently for me even if I target slightly unusual mash pH ranges (for which I have my reasons). I was hoping to only use Brewers Friend from now on, but unfortunately it just doesn't work, at least not in the cases I have looked at.

Take for instance a model mash as follows:

Water:

10L total treated mash liquor with profile:

Calcium 72ppm
Magnesium 9ppm
Sodium 32ppm
Chloride 31ppm
Sulphate 66ppm
Alkalinity 159ppm as CaCO3
pH 7.59

Grist:

3kg of 3 Lovibond base grain.

If I then set the Brewers Friend Advanced Water Chemistry Calculator to add only acid to the mash to target as pH of 5 it suggests 6.28ml of 80% Phosphoric acid.

However, the exact same calculation in Bru'n Water suggests adding only 4.3ml acid.

This is a wildly different amount of acid for such a small and basic mash, and indeed the predicted pH from Bru'n Water if I add 6.28ml is a 4.5, which is enormously off the intended pH of 5.

I can speak from experience and say that the Bru'n Water estimate is far, far closer to what happens in reality than is the Brewers Friend calculator.
I haven't used Bru'n Water and I'm not trying to prove you wrong. I haven't had your experience, that's all, Brewer's Friend has been accurate to less than 0.1 pH units and I can attribute that to variation in my tap water. Are you certain you're using the same acid between both calculators? Default on the Brewer's Friend calculator for phosphoric acid is 10%. Your result using Bru'n Water looks like mine using lactic acid (88%) in Brewer's Friend although for a 10l mash, the amount still looks high. I'd expect your mash to settle out somewhere around 5.5 with no acid at all (guestimating). Another thing to check: Are you treating only the mash water or all of your water? The default in BF is everything, but if you start acidifying the mash to a target pH you have to treat mash water only.

It's an interesting problem. I'm still not convinced it's the calculator. Anyone else having issues with mash acidification?
 
I can guarantee you that what I have put into both calculators is identical, and those are the outcomes. I have only used mash liquor with no sparge for the example, and I have the Brewers Friend calculator set to only acidify the mash water, and likewise in Bru'n Water. Anybody can feel free to use the example parameters provided and compare for themselves, of course.

I would welcome the thoughts of anybody else, all I can say at this point is that the Brewers Friend calculator is unusable for me, and until that changes I'll have to stick to Bru'n Water, but it would be great if it was fixed.
 
I'll try that tonight, too much of a pain on the phone.
 
Okay, I came home and plugged all that information into the Advanced Water Calculator and came up with a requirement of 6.06 ml given your malt bill and salt concentrations to get to pH 5.0. I don't know why you want to go that low but I'm going with it. When I adjust to the normal mash pH, 5.4, the amounts come out reasonable. Your water is more alkaline than mine so the values you get are slightly higher than mine. And as mentioned above, within reason, the calculator hits my numbers pretty accurately. Close enough for homebrew at any rate. I can't explain the difference but given the higher alkalinity of your water and that you're pretty much doubling the acidity (the pH scale is logarithmic so the difference of 0.4 is significant and greater than two), I don't see that the number is unreasonable.

But at the end of the day it's your beer. Make it using the Bru'n Water calculations then take a pH reading - you can always add more acid if needed to reach your target pH. At least that way you'll be more certain of your outcome for the next batch. Full disclosure, I'm not on the Brewer's Friend staff nor do I have any stake whatsoever in being right.
 
Thanks for doing that, at least I know I'm not missing something obvious on the calculator.

As for why I want it that low, there are lots of good chemical reasons to want to push the pH below the traditional range. Despite the commonly held beliefs there are few downsides to mashing low, and numerous upsides if you dig into the literature. If you have never tried it I suggest giving it a go at least once, maybe on a beer you liked the first time you brewed it but found a little rough around the edges. For what its worth I split my acid additions between Lactic and Phosphoric so as to reduce the chance of breaching taste thresholds for the specific ions being added (however the test mashes I have performed to check the calculators have used only phosphoric).

Anyway, that's all beside the point, hopefully somebody from Brewers Friend will respond regarding the discrepancy between Bru'n Water and Brewers Friend, for now I will just stick to Bru'n Water and I suggest anybody reading this do likewise, to be honest.
 
Our water calculations come very close to the actual mash pH, so at this point we would have to see evidence that it’s not in order to make changes in the calculator.

Please let us know of your results. Most people wouldn’t want to mash at such a low pH, but it’s very interesting that you do, and we’d love to hear your reasons and the results.
 
I don't suppose I will use the Brewers Friend calculator again in its current incarnation, so the only way I can give you any data will be to perform test mashes, which I am not particularly inclined to do again at the moment. I would have thought the discrepancy between the two calculators was enough to warrant some investigation, but if not then that's ok, people are busy and water chemistry is only a sexy topic to those who obsess over it.

Regarding the sensory impact of mashing that low (and lower) one big impact it has is the complete removal of tannic flavours from beers through not only protein coagulation but also enhanced protein-polyphenol complexing, which whilst it can be applied by adjusting boil pH down after the mash would seem in my experience to also be beneficial in the mash, where these complexes will have more chance to form before the boil. Further to that the resultant low wort pH leaves the yeast with less proton pumping to do themselves, leaving a more ideal environment for them to work in during the vital growth phase of the fermentation. The last thing that is worth mentioning is that when fermenting under pressure this further reduces the chance of a high finishing pH in the beer, as pressure ferments have been known to suffer from.

Many of these things can be achieved by simply acidifying the wort before the boil and after the mash, but as I say I have personally found that the benefits of doing so in the mash are greater than only doing so in the boil. Your mileage may vary, as with anything. I have run the gamut on mash pH from 5.7 down to 4.5 and find that the region between 4.5 and 5 is where the majority of my beers shine brightest.

EDIT: I recognise there will be many, probably smarter, people who disagree with my assertions here, and all I can say to that is that there is a lot of literature out there to plough through, and by no means all of it agrees, but this is what I have found through a combination of reading and good old empirical experience. So, by all means disagree with me, but don't expect to change my mind, or even for me to argue. I didn't create this thread to get into a discussion about the ideals of brewers, I created it to try to have the calculator rectified.
 
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Thanks for doing that, at least I know I'm not missing something obvious on the calculator.

As for why I want it that low, there are lots of good chemical reasons to want to push the pH below the traditional range. Despite the commonly held beliefs there are few downsides to mashing low, and numerous upsides if you dig into the literature. If you have never tried it I suggest giving it a go at least once, maybe on a beer you liked the first time you brewed it but found a little rough around the edges. For what its worth I split my acid additions between Lactic and Phosphoric so as to reduce the chance of breaching taste thresholds for the specific ions being added (however the test mashes I have performed to check the calculators have used only phosphoric).

Anyway, that's all beside the point, hopefully somebody from Brewers Friend will respond regarding the discrepancy between Bru'n Water and Brewers Friend, for now I will just stick to Bru'n Water and I suggest anybody reading this do likewise, to be honest.
I've noticed acid will sometimes improve the taste of a lackluster beer but I do that adjustment either at packaging or, through testing, in the next batch. I do mash wheat beers and light lagers low (around 5.2) and have found dark beers benefit from going a little higher after the mash (mash at 5.4 for conversion, adjust up to 5.5 for flavor). It's a complex topic - what happens in the mash tun needs one thing, the beer's flavor may need another....
 
Yeah, dosing acid after packaging is a good and enlightening process, but it will of course not go back and alter the chemical processes which the beer, and before that wort, has undergone. It certainly is a complex topic, and one on which I am on the wrong side of the accepted norms, but I don't mind that one bit.
 
Yeah, dosing acid after packaging is a good and enlightening process, but it will of course not go back and alter the chemical processes which the beer, and before that wort, has undergone. It certainly is a complex topic, and one on which I am on the wrong side of the accepted norms, but I don't mind that one bit.
As long as you enjoy your beer, I don't see a problem with that! If there were One Right Way we wouldn't need competitions now, would we? And all our beer would taste the same....
 
I think that’s why Brewing is an art, rather than a science. In fact, I’m not sure it’s even a science, rather a sometimes over dosage of science to try to improve an art.

They didn’t have science, or at least any real measurable amount, per se for beer back then, yet we try to ‘scientifically’ recreate them.
 
I've seen where you compare results from the 2 calculators, but no mention of actually measuring pH. Did I miss something? Have you measured to verify your suspicions? The reason I ask is that many question the model Martin uses in Bru'n Water.
Results are what really matters, so I guess if you're happy with the results of a calculator, its accuracy needn't concern you. I'm just one of those people who needs to know.
 
I think that’s why Brewing is an art, rather than a science. In fact, I’m not sure it’s even a science, rather a sometimes over dosage of science to try to improve an art.

They didn’t have science, or at least any real measurable amount, per se for beer back then, yet we try to ‘scientifically’ recreate them.
I'd be wiling to bet if they had our science, the'd drop their craft in a heartbeat.
 
I've seen where you compare results from the 2 calculators, but no mention of actually measuring pH. Did I miss something? Have you measured to verify your suspicions? The reason I ask is that many question the model Martin uses in Bru'n Water.
Results are what really matters, so I guess if you're happy with the results of a calculator, its accuracy needn't concern you. I'm just one of those people who needs to know.
Yep, in my opening post I mention that I was suspicious of the numbers before I was about to perform a mash so I did a mini mash to check, and found that I needed to almost halve the acid suggested by Brewers Friend, an amount which happened to almost exactly match what Bru'n Water suggested.
 
Yep, in my opening post I mention that I was suspicious of the numbers before I was about to perform a mash so I did a mini mash to check, and found that I needed to almost halve the acid suggested by Brewers Friend, an amount which happened to almost exactly match what Bru'n Water suggested.

Neither this nor your OP were very specific on the matter of actually testing pH. Did you use a reliable and calibrated meter to test pH?
 

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