High FG and PH

[BrewRunning]

I just brewed an IPA, 15 gal batch, that has been in the fermenter for 2 weeks. The FG has been at 1.020 for 5 days straight. Expected FG was 1.011.

I just took a PH reading today and it’s at 5.1, high for a finished beer. Looking back over my brew day notes I realized that I forgot to add the portion of brewing salts that should have went into the boil. Some questions I have;

1. Can I go ahead and add the salts that should have went into the boil?

2. Should that bring the PH down to where it should be?

3. Is the high PH the likely cause of the high FG and do you think it will restart fermentation if the PH drops?

4. Is having that high of a PH for this long bad for the beer?

Also, OG was 1.078 and I pitched 6 smack packs of Wyeast 1056. Mash PH was 5.3.

Thanks for any advice anyone can provide.

 

[BrewRunning]

Maybe this should have been posted in the brew science forum.

I went ahead and added the salts to the fermenter and got the PH down to 4.9. Should I use lactic acid to get the PH down further to the desired 4.4 ish range?

Thanks,

 

[Silver_Is_Money]

Beer can be brewed successfully without any addition of minerals. There are loads of them in the malts. If your yeast has brought the Wort from 1.078 OG to 1.020 and the pH has only dropped from 5.3 to 5.1 during fermentation I suspect a problem with the pH meter.

Your apparent attenuation is 74.4%, which sounds pretty mainstream to me. Fermentation is likely complete.

 

[IslandLizard]

Maybe this should have been posted in the brew science forum.

So moved to Brew Science.

 

[BrewRunning]

Beer can be brewed successfully without any addition of minerals. There are loads of them in the malts. If your yeast has brought the Wort from 1.078 OG to 1.020 and the pH has only dropped from 5.3 to 5.1 during fermentation I suspect a problem with the pH meter.

Your apparent attenuation is 74.4%, which sounds pretty mainstream to me. Fermentation is likely complete.

I’ve recalibrated the PH meter just to make sure and tested it to make sure it was working properly.

The PH was 5.3 during the mash but I didn’t take a reading after sparging or boiling, I know I should have. I suspect that the PH was higher than 5.3 at the beginning of fermentation since I didn’t add the rest of the salts during the boil.

Assuming that the PH is actually at 4.9 now should I go ahead and lower it? The hop flavors are kind of not present right now and I’m thinking it may be due to the PH but wasn’t positive. I also have a dry hop addition to add which I know will also raise the PH slightly more.
Thanks!

 

[Silver_Is_Money]

I'm still not seeing how it could finish at pH 4.9 so I'm very hesitant to tell you to acidify it. Do you know anyone else with a pH meter for a second opinion? What yeast was used?

A drop of ballpark 0.5 - 0.6 pH points for 15 gallons might require on the order of about 8 mL of 88% Lactic Acid.

 

[BrewRunning]

I'm still not seeing how it could finish at pH 4.9 so I'm very hesitant to tell you to acidify it. Do you know anyone else with a pH meter for a second opinion? What yeast was used?

A drop of ballpark 0.5 - 0.6 pH points for 15 gallons might require on the order of about 8 mL of 88% Lactic Acid.

Good idea. I’ll see if I can get someone else to loan me a meter to verify. Thanks for the input!

The yeast was Wyeast 1056, 6 smack packs.

Thanks,

 

[BrewRunning]

I'm still not seeing how it could finish at pH 4.9 so I'm very hesitant to tell you to acidify it. Do you know anyone else with a pH meter for a second opinion? What yeast was used?

A drop of ballpark 0.5 - 0.6 pH points for 15 gallons might require on the order of about 8 mL of 88% Lactic Acid.

So, I just degassed some Corona and got a PH reading of 4.2. That would seem to indicate that the meter is working correctly.

I’m not sure what to do now, as you indicated the amount of lactic acid needed to get the PH in range will probably reveal itself in the beer flavor, is that correct?

Any suggestions?

Thanks,

 

[IslandLizard]

Also, OG was 1.078 and I pitched 6 smack packs of Wyeast 1056.

Yowsers! Why not making yeast starters? Or reusing (partial) yeast cakes from previous brews?

How did you determine the viability of that yeast?
How well did you aerate/oxygenate the wort when pitching?
Underpitching and/or insufficient oxygen can result in under-attenuated or stalled beer.

 

[BrewRunning]

I pulled a sample of the beer and added lactic acid to get to PH of 4.4 and then tasted it. Very noticeable almost sour flavor so.....I don’t think adding enough acid to the batch is going to be a good idea. I guess I’ll just chalk this mistake up as a learning experience and see what the next batch does.

 

[BrewRunning]

Yowsers! Why not making yeast starters? Or reusing (partial) yeast cakes from previous brews?

How did you determine the viability of that yeast?
How well did you aerate/oxygenate the wort when pitching?
Underpitching and/or insufficient oxygen can result in under-attenuated or stalled beer.

Yeah, I would normally harvest the yeast and reuse but this is the first time I’ve brewed in over 6 months so I didn’t have any on hand and time constraints kept me from making a starter.

I normally oxygenate for 60 seconds with an oxygen tank run through the carbing stone but may have forgotten to do that with this batch along with the other mistakes I made. I was a little rusty on this one.

 

[IslandLizard]

I pulled a sample of the beer and added lactic acid to get to PH of 4.4 and then tasted it. Very noticeable almost sour flavor so.....I don’t think adding enough acid to the batch is going to be a good idea. I guess I’ll just chalk this mistake up as a learning experience and see what the next batch does.

Phosphoric acid is lot more neutral in flavor.
Maybe drop it only by a few points, retaste after a few hours, get a 2nd opinion, and don't overdo it.

 

[Silver_Is_Money]

... as you indicated the amount of lactic acid needed to get the PH in range will probably reveal itself in the beer flavor, is that correct?

I did not indicate that. I merely projected an acid amount. I then advised against it due to the potential to drop the pH too much, with the presumption that it does not seem likely that it should be 4.9. Even if you mashed it at pH 6 the yeast should have gotten it below where you are measuring it.

 

[Silver_Is_Money]

I pulled a sample of the beer and added lactic acid to get to PH of 4.4 and then tasted it. Very noticeable almost sour flavor so.....I don’t think adding enough acid to the batch is going to be a good idea. I guess I’ll just chalk this mistake up as a learning experience and see what the next batch does.

'Sour' is a descriptor for palate noticeable acidity levels in general. I'm still concerned that you were likely closer to 4.4 pH (or actually lower, perhaps 3.9 to 4.1, due to using an ale yeast strain) to begin with.

 

[BrewRunning]

Phosphoric acid is lot more neutral in flavor.
Maybe drop it only by a few points, retaste after a few hours, get a 2nd opinion, and don't overdo it.

Thanks for that info! I'm going to hold off making any further adjustments until I verify the PH with another meter.

I did not indicate that. I merely projected an acid amount. I then advised against it due to the potential to drop the pH too much, with the presumption that it does not seem likely that it should be 4.9. Even if you mashed it at pH 6 the yeast should have gotten it below where you are measuring it.

I apologize, this was a poorly worded sentence. I was only saying that you indicated the amount needed and I was assuming the acid, at that amount, would be noticeable at that amount and asking if that was correct. I could have stated that better.

'Sour' is a descriptor for palate noticeable acidity levels in general. I'm still concerned that you were likely closer to 4.4 pH (or actually lower, perhaps 3.9 to 4.1, due to using an ale yeast strain) to begin with.

Which is where I thought the beer should finish as well. I'm still going to get a second PH meter today to test it again but, the PH meter seems to be working correctly. Are there any other factors that would have prevented the expected PH drop during fermentation?

Thanks for all of your help!

 

[Silver_Is_Money]

Are there any other factors that would have prevented the expected PH drop during fermentation?

I'm totally baffled. The only factors I can think of are:
1) It's not done fermenting yet. (perhaps it stalled for some unknown reason)
2) Something added to it greatly increased the worts buffering capacity, to where the yeast can't lower the pH further.

I believe that WY1056 is a generally high attenuator. Despite 74.4% AA being aforementioned as not abnormal in general for yeast, perhaps it is abnormal for this specific yeast. You might rouse the yeast and give it a few more days in the fermenter to see if the FG falls and that changes the pH.

 

[Silver_Is_Money]

What temperature did you ferment at? That might impact attenuation.

Although it is generally not needed sans perhaps for a bit of zinc, did you add any yeast nutrient? Was the water built upon RO?

 

[BrewRunning]

What temperature did you ferment at? That might impact attenuation.

Although it is generally not needed sans perhaps for a bit of zinc, did you add any yeast nutrient? Was the water built upon RO?

Fermented at 152, I use an electric Spike brewing system and the temperature probes are calibrated correctly. I did not add any yeast nutrients other than what is contained in the smack packs.

Yes, the water was built up from RO water. Added Gypsum, CaCl, small amount of epsom and canning salts (as calculated using the spreadsheet). I don't have the exact numbers with me but, I can post those later if it will help. A portion of the additions was added during the mash to get the PH to 5.3. The rest were supposed to go into the boil (which I forgot and added to the fermenter a few days ago).

Yeast was pitched at 64 degrees F and allowed to rise naturally to 68 for fermentation. I increased the temp to 70 degrees after the gravity readings came in at 1.020 for several days thinking that warming up a bit would get the yeast to finish up.

I've tried rousing the yeast a few times by bursting CO2 through the bottom port of the unitank with no luck.

I've read a few things about adding yeast nutrients to kick start a stuck fermentation. I may try that and see what it does.

Thanks,

 

[BrewRunning]

Now that I’m home I have the amounts of salts added;

During mash: 30.6g CaSO4, 4.25g MgSO4, 2.55g NaCl

After fermentation (should have been the boil addition): 16.2g CaSO4, 2.25g MgSO4, 1.35g NaCl

Also, my buddy came over with his PH meter and got the same 4.9 reading that I’m getting.

 

[Silver_Is_Money]

Indeed a strange one. Time for acidification.

 

[BrewRunning]

I’ve decided to let the FG stay where it is, acidify with lactic acid to drop the PH a bit but, probably not as low as I’d like just to keep from having off flavor. Roll with it from there and do better next time.

It will still be a drinkable beer just not exactly the way I planned it.

Thanks for all of the input, I’m still baffled!

 

[BrewRunning]

2) Something added to it greatly increased the worts buffering capacity, to where the yeast can't lower the pH further.

So, last night I began adding lactic acid in small increments and testing the PH and flavor. Even after roughly 7ml of lactic acid the PH only dropped from 4.9 to 4.8. Something has definitely increased the buffering capacity, I just don't understand what it could have been.

So far, no off flavors from the lactic acid, I'm extremely reluctant to add any additional lactic acid in fear of off flavors. I don't have phosphoric acid on hand but, just ordered some. I'll try adding some of that when it arrives to see what happens.

Is there a level of phosphoric acid I should be concerned with being too much added? I know people say it's flavor neutral but, I've never used it and not sure of any other negative effects it may have.

Thanks,

 

[Silver_Is_Money]

If you don't plan to have it in storage for months, and rather intend to promptly consume it, then I would forego any additional acid.

I'm not aware of any limit to the amount of phosphoric acid one can add, but it is an important part of the flavor profile of colas, and they are at about 2.54 pH. So it must impact flavor at some level which is unknown to me. I've always used Lactic Acid or Acidulated Malt for downward pH control.