Adjusted pH with phophoric acid, ruined beer!

[gifty74]

So I had been very interested over the past few years in water adjustments, analyzing my local water report, etc to improve my beers. With most lighter grain bills my mash pH would settle to around 5.7-5.8, which from my readings, could benefit from an adjustment to get it closer into the 5.2-5.4 range. I started using 10% phosphoric acid as I read several sources that said it is a good choice to lower pH as it has minimal affect on flavor, and that you cannot perceive it's taste in wort/beer. So the first few batches I found that 10% solution is very weak, and it took so much to adjust a few tenths of a pH unit that it was too much work. So I switched to food grade 85% phosphoric acid.

On the most recent batch of IPA I was right around 5.6-5.7 after dough-in. I used about 1.5 ml which dropped it right to 5.2. I felt good, that I was hitting my target pH, and the rest of the session went well. I'm now tasting the finished beer and could detect a very noticeable tartness / twingy taste that lingered very long after the initial taste. I tried it on multiple occasions and dumped the glass as it was far from enjoyable. So last night I had the notion that it might be the phosphoric acid. So I poured a pint, and added a few drops (4-5) of the 85% acid, and sure enough, it magnified the sour/tart flavor! So I've come to the conclusion that the phosphoric acid ruined my beer! Well that stinks. Now not sure what advice to follow. I surely know I'm not adjusting with that acid anymore. Any suggestions?

 

[porterpounder]

Switch to 88% lactic acid. In the quantities used for mashing/sparge adjustment does not lead to off flavors and works quickly and effectively.

 

[gifty74]

So what is your starting pH when you add the 88% lactic, and how much do you need to add to drop it into the 5.2-5.4 range?

 

[seven9st_surfer]

After building my water from 100% RO, and adding all the salts for whatever profile I'm looking for, I'll add a few oz of acidulated malt to my grain bill to bring the pH down where I want it. I use a combination of Bru'n Water and Brewers Friend, and they're usually within about 0.03 pH of each other, and my actual reading right in the middle of them. Been doing it this way for about a year, and have had no issues.

 

[gifty74]

Ok. Before I invest in an RO system, I can get RO water in 5 gal increments for about $2 from the local grocery store. I could fill 2 carboys and use that for this weekend's brew session. So if I am brewing a 2xIPA this weekend, with 100% RO water, where do I start with salts & adjustments?

 

[seven9st_surfer]

I get RO water the same way. As for the adjustments, it depends on what you're making, for a double IPA, I'd go with the "yellow dry" profile from the Bru'n Water spreadsheet. I then add that as a water profile on Beersmith. Then, using the water profile tool, it'll automatically come up with the recommend salts to add. Then I take those additions and plug them into both Brewers friend water calculator and Brun, both of which take your grain bill and salts into account, and give you an estimated pH level. Then I just add acidulated malt to the grain bill an oz at a time until the pH is where I want it. Hope all that made sense.

 

[jtp137]

So I had been very interested over the past few years in water adjustments, analyzing my local water report, etc to improve my beers. With most lighter grain bills my mash pH would settle to around 5.7-5.8, which from my readings, could benefit from an adjustment to get it closer into the 5.2-5.4 range. I started using 10% phosphoric acid as I read several sources that said it is a good choice to lower pH as it has minimal affect on flavor, and that you cannot perceive it's taste in wort/beer. So the first few batches I found that 10% solution is very weak, and it took so much to adjust a few tenths of a pH unit that it was too much work. So I switched to food grade 85% phosphoric acid.



On the most recent batch of IPA I was right around 5.6-5.7 after dough-in. I used about 1.5 ml which dropped it right to 5.2. I felt good, that I was hitting my target pH, and the rest of the session went well. I'm now tasting the finished beer and could detect a very noticeable tartness / twingy taste that lingered very long after the initial taste. I tried it on multiple occasions and dumped the glass as it was far from enjoyable. So last night I had the notion that it might be the phosphoric acid. So I poured a pint, and added a few drops (4-5) of the 85% acid, and sure enough, it magnified the sour/tart flavor! So I've come to the conclusion that the phosphoric acid ruined my beer! Well that stinks. Now not sure what advice to follow. I surely know I'm not adjusting with that acid anymore. Any suggestions?

Is your PH meter calibrated? Maybe the PH dropped well below 5.2 I have had this happen to me before the finished beer PH was really low and the beer was tart

 

[Foosier]

I use 85% phosphoric acid to adjust my water before every mash. I have never noticed a "twangy" off taste in any of my beers. For the record, I am usually using 6+ ml to adjust my water.

Also, just putting the acid into a finished beer does not prove anything. Lowering the finished beer PH could be triggering other flavor components to be more prominent. Have you tried putting the acid in water to see if you can perceive a flavor?

Be careful blaming one factor until you have looked at all of the other factors which could be impacting your beer (Ferm temps, mash temps, etc...)

 

[JonM]

I think the simple answer is that 5.2 is too low. Mash pH at 5.2 can produce tartness. You want to shoot for 5.4ish.

 

[gifty74]

I use 85% phosphoric acid to adjust my water before every mash. I have never noticed a "twangy" off taste in any of my beers. For the record, I am usually using 6+ ml to adjust my water.

Also, just putting the acid into a finished beer does not prove anything. Lowering the finished beer PH could be triggering other flavor components to be more prominent. Have you tried putting the acid in water to see if you can perceive a flavor?

Be careful blaming one factor until you have looked at all of the other factors which could be impacting your beer (Ferm temps, mash temps, etc...)

I hear you on that. I do have to make absolutely sure that is the culprit, but this tart/twang flavor was pretty prominent, and that exact flavor/mouthfeel was increased in strength when I added the drops of pure acid. I will try tonight in water and see if I get the same flavor, but I'm most certain I will. The rest of my process is pretty sound, recirculating infusion mash (temp controlled), controlled ferm temp, etc.

 

[Homercidal]

If you tested your pH right after dough in, and then dropped the acid in, it was probably still drifting downwards. I'm betting your actual pH after a few more minutes was below what you would want.

And adding a few drops in a pint of beer is WAY too much acid for a fair comparison. That is like several ounces of acid in a 5 gallon batch.

I've been using Phos for a while and like it. I use a few ml of acid per batch, depending on the grain bill. If you need a lot more than that, you might want to dilute your water with some RO or Distilled water to reduce the need for acid.

 

[ajdelange]

Switch to 88% lactic acid. In the quantities used for mashing/sparge adjustment does not lead to off flavors and works quickly and effectively.

Not so fast. For the same pH shift you will have the same number of lactate ions with lactic acid as you will have biphosphate ions if you use phosporic acid and lactate ions are more flavorful than phohsphate. If minimum flavor influence is desired phosphate is the better choice.

The problem here is too much acid. People get the impression that they can neutralize however much alkalinity they have by using acid failing to keep in mind that if you neutralize 5 mEq/L alkalinity that way you are going to have replaced them with 5 mEq/L of the acid anion. At high enough levels of alkalinity the anion is going to become perceptible.

The use of phosphoric (or lactic or better yet sauermalz as some like the flavor) is fine for dealing with modest levels of alkalinity but if the water is heavily alkaline it should be decarbonated first by lime treatment or heating and then the alkalinity those processes leave behind can be taken out with acid.

 

[gifty74]

Ok, to help, my source water:

pH: 7.5
Ca: 29
Mg: 7.8
Na: 11.8
Cl: 22.5
SO: 30
Hardness: 112

 

[ajdelange]

Assuming that "SO" is your sulfate as sulfate your alkalinity is about 1.3 mEq/L. You should be able to knock that out with either phosphoric or lactic without exceeding flavor threshold. So I think, as others have suggested, that you may have overdosed the acid. What is the pH of the finished beer? It should be over 4 and if it isn't you are in lambic/gueze/berliner weiße territory and it is going to taste sour whichever acid you used.

 

[gifty74]

I'm going to measure the finished beer pH tonight after bringing up to room temp and driving off as much co2 as possible. SO, yes, is Sulfate from my water report.

But, with only adding 1.5ml of 85% phosphoric acid, surprise it would've imparted flavors.

Beersmith is saying to drop from 5.7 to 5.4, I'd need to add 4.8ml!!

 

[bob1852]

What temperature was your wort when it read 5.2?

We usually refer to the desired pH at a room temperature sample. At mash temps, your pH will be much different than at room temperature...

 

[gifty74]

I had pulled a sampled and put in the freezer to cool. I usually go by feel, when it doesn't 'feel' warm, but in the future will be using my chef alarm to get a solid temp reading. It def wasn't at mash temps, was close to 70-80F.

 

[gifty74]

So for my upcoming DIPA this weekend, I'm thinking of going the route of buying RO and adding salts. Not sure this is necessary, but you can lmk your opinions on that. Anyway, if I use Beersmith, 11.25 gal of mash water, and adjusting to get a pretty middle of the road medium body IPA water profile with a Sulfate/Chloride ratio of around 2, here's what I will need to add (attached pic). I assume this is about right. But I keep thinking my base water isn't too bad, but might be ready to try it going from a clean slate as I can get 5 gal of RO for around $2.

 

[seven9st_surfer]

If you use chalk, make sure you dissolve it in carbonated water first, only real way to make sure it fully dissolves

 

[JonM]

You definitely don't want that chalk in there.

 

[gifty74]

Yeah, I wasn't going to bother for ~1g. I guess BS just put that in there to add some calcium without anymore sulfate (like a CaSO4 addition). I used the "Match Target Profile" button and BS tries to calculate all of the salt additions for you, I didn't enter any of the salt amounts. I'll just ditch the chalk.

 

[TheHopfather]

Why would you add chalk and then add acid? Leave the chalk out.

 

[gifty74]

On the other hand, this is what BS is saying should be the approach using my base Lancaster, PA water from my local water report...

 

[gifty74]

So I think I'm starting to figure this out. In all prior batches, I had been shooting for 5.2 pH, but I was measuring at room temp. We want the mash pH to be 5.1-5.3 so that's what it needs to be in my mash tun at 150F. I was cooling my sample down, and then measuring, and then adjusting to get the cooled sample down to 5.2. Not correct! I should've been shooting for 5.4-5.5 at room temps. This 'sour' batch I'm most certain I adjusted with my 85% phosphoric acid and got it down to 5.2 at room temp, leaving the mash most likely under 5. I still need to bring a sample up to room temp and measure the finished beer pH, that should answer all of these questions.

 

[gifty74]

Brewed a DIPA on 9/17 and just now getting to finally taste it. Has the same very slight twang in the aftertaste. Def seems like again a result of overdosing with the phosphoric acid. This batch also has the issue of a higher FG than planned as the yeast were not as active as I expected them to be, and the beer ended up at 1.018 FG. Part of the problem with the mash process was I checked the pH too early in the mash process (around 5 min after doughing in) and it was reading 5.7 at room temp. Added 2.5ml of phos acid, and checked again and it was only down to 5.6 (about 10 mins in at this point). Added another 2.5ml and by then it was down to 5.2-5.3 at room temp, and might have dropped even further by end of the mash, which is obviously in the too acidic range, which I'm guessing is what I'm tasting. However, the wort pH before boiling was 5.4, so didn't think I was too low at that point, but the overdose of phos acid must have lingered and has showed up in the final beer. This next batch I've just resolved that I cannot dose 5ml into a fairly light DIPA grain bill. Going to treat my mash water with 2.5ml and dough in and see where it's at. I also have lactic acid now so could use that. John Kimmich recommended I try that as that is what he prefers.

Any chance that old hops could be contributing, or making this acidic aftertaste? I've had them in mason jars in the freezer, but they are 2014 crop hops. They aren't quite as aromatic as they once were and just thinking maybe they are degrading to the point of contributing off flavors. Maybe not...

 

[hotwatermusic]

I think all ph readings are done at room temps for the sake of stable and accurate measurements. The range at mash temps aren't so important because the range of acceptable ph for enzymatic activity is somewhat forgiving. Those guidelines for ph by style are about maximizing character for a given style and are a little more exact, at least anecdotally. On a side note your local water isn't bad and if it tastes good I'd just get used to working with that, being sure to always add some calcium, which you would definitely have to do with RO or distilled anyway. I personally trust bru'n water and find that it is always within a tenth of a point at worst. You may want to give a few different water calculators a trial to see if the numbers you have been getting from your current source are at least in the ball park. I would also try rechecking ph later in the mash to make sure your first number was at least somewhat normalized and that the acid had been adequately mixed and effective. The ph will change some but not drastically, several hundredths maybe. I also have found using liquid acid is more consistent and precise than acidulated malt.

 

[ajdelange]

Most malts have a buffering capacity of around 45 mEq/kg•pH. 10% phosphoric acid is about 1 N while 85% is about 14.8 N and, thus 14.8 times stronger than 10%. If you have a mash of 5 kg (11 lbs) then you should expect a pH drop of 1.5*14.8 /(45*5) = 0.1 pH from the addition of 1.5 mL of 85% acid (equivalent to 22 mL of the 10% strength acid). You should not have had trouble doing this so something else must be wrong. You should not see a drop from 5.7 to 5.2 upon adding 1.5*14.8 = 22.2 mEq of acid to 5 kg grain. Even were your grain to have had half the usual buffering capacity the pH drop would have been only 0.2 and you saw twice that. So I'd start looking at the pH measurements. Do the meter stability check, make sure buffers are fresh etc.

 

[gifty74]

Well, to clarify, 6 gal batch, 10.5g total water, 6g mash water, 15.5 lbs of 2-row, 1 lb of crystal 30, and .75lb white wheat. I added 5ml of 85% phosphoric total. Starting pH was 5.7, and the low bottomed out at 5.3, but it trickled down to 5.2 at one point. I think it was right in between the two. I did just get 88% lactic, so might give that a go this weekend. Trying the exact same grain bill, some new '16 hops, and going to be more careful with the acid additions. Of note also, I did add 17g of gypsum to the total water (10.5gal) as well. Doesn't gypsum have some buffering power?

Also, Ward Labs just got my water sample, so by tomorrow (and before the brew session this weekend) I'll know my exact water as well.

See the attached image. Beersmith is saying with this grain bill that I'll need close to 8ml of 88% lactic acid. How close does this sound? I don't think I'll be adding that much, planning to add half and will check 15min into the mash and add more if needed. That's if I measure at room temp after taking my sample, I should see 5.7 (which is really 5.5 in the mash, at mash temp). To drop to 5.2 that's a .3 drop, so I should see 5.4 at room temp (which would be 5.2 in the mash).

 

[ajdelange]

Well, to clarify, 6 gal batch, 10.5g total water, 6g mash water, 15.5 lbs of 2-row, 1 lb of crystal 30, and .75lb white wheat. I added 5ml of 85% phosphoric total. Starting pH was 5.7, and the low bottomed out at 5.3, but it trickled down to 5.2 at one point. I think it was right in between the two.

Throwing together some similar malts in the amounts you list with 6 gal strike water with alkalinity of 1.1 mEq/L and calcium hardness of 1.5 gives a predicted mash pH of 5.71 so the grist model isn't too far off from what you have. Adding 5 mL of 85% phosphoric acid to this lowers the mash pH estimate to 5.48. When measuring mash to which acid has been added it is quite difficult to get it mixed in uniformly unless the mash is very thin. Furthermore, it takes some time for the acid to penetrate the grist material where its protons are abstracted. Thus it is not only possible but likely that one will sometimes observe pH values alarmingly below what one is shooting for at least early on. With thorough mixing and a wait of about 20 minutes mash pH stabilizes. I'm guessing that this may be what you saw. Had you sampled later and/or mixed more thoroughly I'm guessing you might have seen a final mash pH closer to the prediction (5.5).

I did just get 88% lactic, so might give that a go this weekend. Trying the exact same grain bill, some new '16 hops, and going to be more careful with the acid additions.

It seems your acid additions are reasonable. Also note that if you think phosphoric acid adds too much flavor switching to the amount of lactic acid required to do the same job will only make things worse.

Of note also, I did add 17g of gypsum to the total water (10.5gal) as well. Doesn't gypsum have some buffering power?

Yes, it does at pH -10 and +1.9. In the pH region of brewing it has none.

I don't think I'll be adding that much, planning to add half and will check 15min into the mash and add more if needed.

This would be a wise approach if it didn't take 20 minutes for acid to mix in and react. A better approach is to make a test mash (about a pound of grist) with the acid scaled to the corresponding fraction of the total. If the test mash pH comes out too high, you need more acid and conversely.

That's if I measure at room temp after taking my sample, I should see 5.7 (which is really 5.5 in the mash, at mash temp). To drop to 5.2 that's a .3 drop, so I should see 5.4 at room temp (which would be 5.2 in the mash).

You want to hit 5.4 - 5.6 at room temperature. Mash pH will be what it will be (the difference between mash and room temperature depends on the malt.)

 

[gifty74]

Thanks ajdelange. Looks like I'm not too far off base with my assumptions. I hear ya on the switching to lactic. I am at least considering it based on the acidic notes I'm tasting in the last 2 beers I adjusted with the 85% phosphoric. I'm thinking maybe it's stronger than 85%, or maybe processed incorrectly to give some nasty off flavors? Not really sure. The lactic I got is food grade, 88%. Also John Kimmich advised that I ditch the phosphoric and use lactic like he does.

John also suggests brewing the same batch over and over until you nail it. After 2 or 3 batches with the same malt bill (assuming source water doesn't change) you should be able to nail a 5.2 mash pH. So this time I'm thinking 3ml of phosphoric, or 5ml of lactic in the mash water, along with the gypsum. Mix it all in good in the water and then dough-in. Then let that soak in and adjust and check at 15-20mins this time.