Low Stout pH; Below Predicted in Bru'n Water

[BeeSpojj]

Hey everyone,

Currently brewing my first stout and things got off to a rough start. For reference, here is the recipe I am trying to follow: . I did not follow his water additions since he does not use RO water (I believe).

Here is my recipe (2.8 gallon batch):
-4.00 lbs Pale Ale (LHBS did not have golden promise)
-0.9 lbs flaked barley
-0.45 lbs chocolate malt
-0.4 lbs roasted barley

Water Additions (I am using 5.33 gallons of water total, I add all of my salts to the total water)
-Gypsum: 0.5g
-Calcium Chloride: 0.5g
-Epsom: 1.1g
-Calcium Carbonate: 1.9g (probably should have used baking soda)
-Salt: 1.1g
-Lactic Acid: 1.5mL

Final Water Profile:
-Calcium: 53 ppm
-Magnesium: 5 ppm
-Sodium: 57 ppm
-Sulfate: 35 ppm
-Chloride: 49 ppm
-Bicarbonate: 122 ppm
-Predicted pH: 5.5

10 minutes into the mash I took a pH reading (I currently use pH strips, in past brews they have been reliable in telling me the ballpark which has been accurate to Bru'n Water predictions) and pH was apparently siting around 4.5. I added 2.75 grams of baking soda which brought the pH back up to around 5.5 - 5.7. There have been threads that suggest adding the roasted grains at the end of the mash to prevent a pH drop, but in the video he added everything at the beginning of the mash. I can't seem to figure out where I went wrong, normally my Bru'n Water predictions are dead-on to what I measure. So why did this one drop so low? I thought it may have been something about the dark colour of the wort that was maybe throwing off the strips, but then I watched videos that also used strips and it was giving them proper results, confirming that my pH was just that low. Any suggestions would be greatly appreciated for my next attempt. Hopefully I can save this beer.

 

[Jag75]

With stouts the grain bill lowers the ph . Hard to determine what water he's using if he doesn't say. It really depends what the tap water is .

For instance, my water brews great dark beers. Not so much for light beers . So when I brew lighter ales or lagers I use RO and build . Stouts I just use tap water. If I were to add lactic acid to my mash water during a stout brew my ph would drop below what I'm aiming for .

However if Bru N Water had your ph at a certain level with all those additions im not sure what happened. That program has always been on the $ for me. Maybe you checked the ph too early . I usually check closer to 20 min in .

 

[BeeSpojj]

Thanks for the response! I just build all my profiles off RO as I find I'm more consistent. Without the lactic acid addition, Bru'n Water predicts my pH at 5.9 which seems super high, even with the roasted grains. This is why I added the acid, originally I was hoping to not have to.

 

[McKnuckle]

I brew 2.5 gallon batches, and your 1.5 mL of lactic acid (never needed in a stout) is near to what I might add to the palest beers I brew. Don't add acid to beers with dark roasted grains. Your water profile without that acid should have been at least in the ballpark.

Also, that's a lot of Epsom salt and still claiming to be 5 ppm. I wouldn't add that at all either.

 

[BeeSpojj]

I brew 2.5 gallon batches, and your 1.5 mL of lactic acid (never needed in a stout) is near to what I might add to the palest beers I brew. Don't add acid to beers with dark roasted grains. Your water profile without that acid should have been at least in the ballpark.

Also, that's a lot of Epsom salt and still claiming to be 5 ppm. I wouldn't add that at all either.

Thanks for the reply. So if I left out the acid and stayed with the predicted pH of 5.9, that would still be expected to drop the the 5.4-5.6 range? Instead of the Epsom would you add more gypsum? Again, this was my first time experimenting with stouts so I might be missing something obvious.

 

[McKnuckle]

Honestly, that 5.9 sounds really off. I realize Bru'n is popular software and I've used it too. But maybe there was a mistake in data entry? I'll try plugging in that recipe to see what I come up with.

I typically adjust water for stout by ensuring that Ca is at least 50 ppm, Cl and SO4 are in the 50-100 range (one or the other, then the other one roughly half that), and then adjust Na with baking soda to achieve a mash pH of 5.45-5.5. I ignore Mg. Mash pH is always too low without the baking soda.

 

[BeeSpojj]

Honestly, that 5.9 sounds really off. I realize Bru'n is popular software and I've used it too. But maybe there was a mistake in data entry? I'll try plugging in that recipe to see what I come up with.

I typically adjust water for stout by ensuring that Ca is at least 50 ppm, Cl and SO4 are in the 50-100 range (one or the other, then the other one roughly half that), and then adjust Na with baking soda to achieve a mash pH of 5.45-5.5. I ignore Mg. Mash pH is always too low without the baking soda.

It's possible I messed up somewhere in the software but nothing jumped out at me. Thanks for the input though, I really appreciate it. I'll mess around with those additions. Let me know if you find any errors when you have a chance to run it through.

 

[McKnuckle]

I can't literally match your water volumes, but I can come close. Brewfather predicts a 5.48 mash pH in distilled water with no additions at all. Once I add what you added (minus the acid), it comes out to 5.62. Interestingly, the acid drops it to 5.47, which should be a good pH.

Notice, though, that you're adding competing factors - minerals that raise alkalinity and then acid that competes with it. It's not "wrong" but it's more complicated than it may need to be.

Take my minimalist approach for comparison; add 2g of both gypsum and CaCl, then 1.6g baking soda, and you're also at 5.49 pH.

Admittedly, I didn't use Bru'n Water for this as I'm not in front of the right computer at the moment... But I do use Brewfather with success.

 

[JimRausch]

I skimmed through the other answers and didn't see anything that addresses what I think may be your main issue: adding Calcium carbonate, which is chalk and basically inert and doesn't even dissolve unless the pH drops below the level you're dealing with. Then you added lactic acid which does work well in dropping pH. Not surprising that with the dark grains you were sitting at 4.5. So next time, when figuring it out in Brun water, skip the CaCO2 and if you need to increase pH, use either baking soda or pickling lime.

 

[BeeSpojj]

I can't literally match your water volumes, but I can come close. Brewfather predicts a 5.48 mash pH in distilled water with no additions at all. Once I add what you added (minus the acid), it comes out to 5.62. Interestingly, the acid drops it to 5.47, which should be a good pH.

Notice, though, that you're adding competing factors - minerals that raise alkalinity and then acid that competes with it. It's not "wrong" but it's more complicated than it may need to be.

Take my minimalist approach for comparison; add 2g of both gypsum and CaCl, then 1.6g baking soda, and you're also at 5.49 pH.

Admittedly, I didn't use Bru'n Water for this as I'm not in front of the right computer at the moment... But I do use Brewfather with success.

Thank you for the input, definitely going to try out that approach next time. On a side note, I can't thank you enough for responding to my last post about volumes last year. Ever since, I've been able to brew with consistent volumes and haven't had any gravity issues since!

 

[BeeSpojj]

I skimmed through the other answers and didn't see anything that addresses what I think may be your main issue: adding Calcium carbonate, which is chalk and basically inert and doesn't even dissolve unless the pH drops below the level you're dealing with. Then you added lactic acid which does work well in dropping pH. Not surprising that with the dark grains you were sitting at 4.5. So next time, when figuring it out in Brun water, skip the CaCO2 and if you need to increase pH, use either baking soda or pickling lime.

Thank you for the reply! I had a feeling this may have contributed, definitely regretted adding it as soon as it went in. I'll take this into consideration next time as well.

 

[BeeSpojj]

Overall, good news. Adding the baking soda to fix the pH must have saved my mash. Just finished brewing and even with the mash issues, still managed to get a perfect original gravity.

 

[McKnuckle]

On a side note, I can't thank you enough for responding to my last post about volumes last year.

I'll take your word for it that this happened! Very glad to help.

 

[VikeMan]

Unless I missed it. you didn't mention your strike water volume, which (because you mineralized all the water at once) would matter to the pH, i.e. the amount of minerals that got into the mash was dependent on your strike volume. What was it?

 

[mabrungard]

The chalk addition is a complete waste of time. The pH fell due to that.

 

[VikeMan]

The chalk addition is a complete waste of time. The pH fell due to that.

Even assuming zero dissolution of chalk, there must be more going on than that. With OP's grain bill, the bulk water profile he built (ignoring chalk), and 1.5 ml (88%) lactic acid added to the mash, I get a pH or 5.24 at 1 quart pert pound or 5.22 at 2 quarts per pound, using Mark's model. I don't see anything in the story that would account for the initial pH of 4.5.

That said, I am always suspicious of any test strip measurements.

 

[Jtvann]

Someone correct me if I’m wrong here.

Acid’s one and only use is lowering pH
Chalks one and only use is raising pH

Now I know chalk also brings some calcium, but it’s better to get your calcium from somewhere else. Also the addition of calcium that the chalk will bring is mostly unimportant.

When I use bru’n water, I do it in conjunction with Beersmith 3. Beersmith has an algorithm in the water tools profile that will match a target profile, telling you the best ratios to use. I plug all the numbers in from bru’n water to beer smith, then run the algorithm. Put the results back in bru’n water.

After that, if pH is high, I incrementally kick up acid. If it’s low, I incrementally kick up chalk.

I’m brewing a brown ale today that needed some chalk to raise pH. I’d not researched slaked like until last night. I knew chalk to be fairly insoluble, but not completely insoluble. Am I to understand that the chalk will do nothing for me?

 

[dmtaylor]

I'm still reviewing everything above, but for now I can tell you, you should never need to add lactic acid to a stout. If anything, you need to add baking soda or pickling lime to bring the pH up. With 15% dark roasted grains in the mash, this brings the pH down 0.4, from roughly 5.8 to about 5.4. In my opinion, you should have a goal of closer to 5.55 to 5.6, so it was already low, and then you added lactic on top of it.

Oh yeah, and chalk. It doesn't dissolve. Didn't do anything for you.

The above is my own independent response without reading any other comments. I'll edit my response with more info momentarily...

EDITS:

Took me a while to read all the comments. Sorry I was so late to the party, I'm caught up now.

Yeah..... it was the lactic acid. Odd to add that in a stout. Lots of great answers above. @Jag75, @McKnuckle, and @JimRausch all had it right, with great points by @VikeMan and @mabrungard (!) as well.

Someone correct me if I’m wrong here.

Acid’s one and only use is lowering pH
Chalks one and only use is raising pH

Now I know chalk also brings some calcium, but it’s better to get your calcium from somewhere else. Also the addition of calcium that the chalk will bring is mostly unimportant.

When I use bru’n water, I do it in conjunction with Beersmith 3. Beersmith has an algorithm in the water tools profile that will match a target profile, telling you the best ratios to use. I plug all the numbers in from bru’n water to beer smith, then run the algorithm. Put the results back in bru’n water.

After that, if pH is high, I incrementally kick up acid. If it’s low, I incrementally kick up chalk.

I’m brewing a brown ale today that needed some chalk to raise pH. I’d not researched slaked like until last night. I knew chalk to be fairly insoluble, but not completely insoluble. Am I to understand that the chalk will do nothing for me?

Chalk has a lot of uses... classrooms, hopscotch, possibly in drywall (although I think that's mostly gypsum).... meanwhile, chalk should only rarely be useful in brewing. For raising pH, use pickling lime or baking soda instead, they actually dissolve. You're right about all the rest of it. I use acid and pickling lime to adjust pH down or up, respectively. To add both in one brew (or chalk for that matter) is usually indicative of the brewer not really understanding what they are doing with mineral additions. Use one or the other, not both... and not chalk.

 

[McKnuckle]

It was a combination of things added to compensate for things that didn't have to be added in the first place. The chalk was added, which raised the pH (on paper), so acid was added (again on paper) to compensate. In practice, though, the chalk didn't work, so the acid tanked the pH.

Didn't have to add either one.

 

[dmtaylor]

It was a combination of things added to compensate for things that didn't have to be added in the first place. The chalk was added, which raised the pH (on paper), so acid was added (again on paper) to compensate. In practice, though, the chalk didn't work, so the acid tanked the pH.

Didn't have to add either one.

Excellent summary. Exactly right.

 

[Craiginthecorn]

I often have found that the pH calculations are the least precise aspect of virtually all of the recipe tools, including Brewfather, Bru'n Water, and Beersmith 3. It's been my experience that I do not need to add all of the acid predicted by the tools, so I have started adjusting my target pH upward by 2/10ths in the tool. For a Pilsner, for example, I would target 5.4 instead of 5.2, then adjust as needed to get to my real target of 5.2 while brewing. With starch conversion happening so quickly with today's highly-modified malts, I want to be in the neighborhood of my target from the start of the mash and this method achieves that while minimizing the chances of overshooting.

 

[dmtaylor]

I often have found that the pH calculations are the least precise aspect of virtually all of the recipe tools, including Brewfather, Bru'n Water, and Beersmith 3. It's been my experience that I do not need to add all of the acid predicted by the tools, so I have started adjusting my target pH upward by 2/10ths in the tool. For a Pilsner, for example, I would target 5.4 instead of 5.2, then adjust as needed to get to my real target of 5.2 while brewing. With starch conversion happening so quickly with today's highly-modified malts, I want to be in the neighborhood of my target from the start of the mash and this method achieves that while minimizing the chances of overshooting.

May I ask...... are you measuring pH in a cooled sample? Or are you measuring it directly at mash temperatures of approximately ~150 F (65 C)? This might explain your difference, since all the softwares assume cool room temperature measurements... whereas commercial breweries often measure at mash temperatures. Many people have noted differences of 0.20 to 0.25 between the two temperatures.

 

[Craiginthecorn]

It was a combination of things added to compensate for things that didn't have to be added in the first place. The chalk was added, which raised the pH (on paper), so acid was added (again on paper) to compensate. In practice, though, the chalk didn't work, so the acid tanked the pH.

Didn't have to add either one.

This sort of phenomenon is something I've encountered using automatic water calculations in Brewfather -- too many additions to achieve the result. Not always, but sometimes. It's why I prefer using Bru'n Water.

In truth, I usually use two tools to do the calculations because it's also fairly easy to shoot yourself in the foot with Bru'n Water, so using two tools is a sanity check. It's a great tool, but it's not an Easy Button solution.

I got lazy with my last batch of saison and didn't initially use Bru'n Water, but when I started measuring my mineral additions and I got to the point where Brewfather's recipe had me adding 6+ grams of gypsum to 18 liters of mash water, I stopped and recalculated with Bru'n Water. I ended up using less than 1/4th that amount.

The recipe creator tools are continuing to refine their water salts calculations and now even the Grainfather app has it as a beta feature. Beersmith recently provided an option to use an alternative method for calculating predicted pH, which was said to recommend smaller acid additions, which supports my observation about needing less acid than predicted.

From Beersmith's release notes: "I’ve added an additional mash pH model based roughly on the popular BNW calculator. The previous BeerSmith mash pH calculator used the MPH model but some brewers preferred an alternate model so now you can select which mash pH model to use on the mash tab. In general the two models are very close with mash pH estimates, but the BW model will result in much less acid needed to adjust the pH than the MPH model".

@mabrungard, which of these pH calculation methods is Bru'n Water using?

 

[Craiginthecorn]

May I ask...... are you measuring pH in a cooled sample? Or are you measuring it directly at mash temperatures of approximately ~150 F (65 C)? This might explain your difference, since all the softwares assume cool room temperature measurements... whereas commercial breweries often measure at mash temperatures. Many people have noted differences of 0.20 to 0.25 between the two temperatures.

Yes, I do chill my samples. I use minimal volumes to allow for quick cooling and keep a small bowl of ice water handy for chilling quickly. My pH meter usually shows my samples to be in the 20-23 C range.

 

[McKnuckle]

I never use any tools that tell me what to add to achieve a pre-determined profile. I find that these tools add too many components, and trying to literally match a full profile is unnecessary. The bicarbonate content, I think, is the gotcha in this process. Nobody needs to match HCO3 in a profile. That's probably why chalk and salt were in your latest set of "instructions."

Magnesium is also something that arguably never needs to be matched.

The section at the bottom of Brewfather's "Calc" tool on the recipe lets you just plug in values for the additives you want to work with, and will reveal the end product interactively. It's very easy to use. Try it if you haven't already.

 

[dmtaylor]

Yes, I do chill my samples. I use minimal volumes to allow for quick cooling and keep a small bowl of ice water handy for chilling quickly. My pH meter usually shows my samples to be in the 20-23 C range.

Hmm. Then that's odd. Brun'water turns out pretty accurate for most people. (I myself use an independent program that nobody ever heard of, works for me.)

 

[Craiginthecorn]

The section at the bottom of Brewfather's "Calc" tool on the recipe lets you just plug in values for the additives you want to work with, and will reveal the end product interactively. It's very easy to use. Try it if you haven't already.

I agree with your points.

I notice that if I enter my salt additions from Bru'n Water in Brewfather, the resulting profiles match, so the calculations similar. But for now, I don't trust Brewfather's auto calculation feature.

 

[Craiginthecorn]

Hmm. Then that's odd. Brun'water turns out pretty accurate for most people. (I myself use an independent program that nobody ever heard of, works for me.)

Define "pretty accurate". I think being within .2 is pretty accurate.

 

[McKnuckle]

The math for calculating how much ion concentration a given addition provides to the water is trivial. All the software does that part right. It's the "auto-generate a set of additions to achieve a target profile" feature that I'd avoid in all of the programs.

 

[dmtaylor]

Define "pretty accurate". I think being within .2 is pretty accurate.

Closer to 0.1 is my understanding of many results, and better defines "pretty accurate" than 0.2 in my humble opinion. But like I said, I don't use that software so I wouldn't really know how accurate it is from personal experience either, but only based on what I've heard.

 

[ScrewyBrewer]

This year I've come to rely on auto calculated mineral and acid additions after verifying the brewing results. In my opinion, the key to getting it right is in entering target water profiles that are ion balanced.

 

[VikeMan]

In my opinion, the key to getting it right is in entering target water profiles that are ion balanced.

Surely you're not suggesting that there are published water profiles out there that are not balanced!

 

[Jtvann]

Closer to 0.1 is my understanding of many results, and better defines "pretty accurate" than 0.2 in my humble opinion. But like I said, I don't use that software so I wouldn't really know how accurate it is from personal experience either, but only based on what I've heard.

My last two beers, I targeted 5.2 and 5.5. My 5.2 hit exactly 5.2, which was the video I referenced above. My 5.5 hit 5.4. I’m happy with bru’n water.