PH drop too low, too quick - Yeast Issue?

[Anavrin215]

In moving to Philly, I’m working on getting familiar with the general water profile (which is generally on the harder side), but have noticed on my last two beers, the PH (post boil and into ferm) of 5.2, drops substantially after day 1 (which make sense), but then continues to drop a good deal into the second day, making a simple pale ale, more on the acidic side.

After day 1 it goes from 5.2 to 4.1 (which is already a bit on the lower end), but then from day 2 to 3, it goes from 4.1 to 3.5! Which is certainly too low to be enjoyable for the style.

A few things to note:

• I’m using a 1.25L starter of Imperial Flagship yeast. Stipulate for about 20-24hrs and pitched at 72~ (ferm at 68)
• Early Mash PH = 5.3, after sparge went down to 5.2, post boil was 5.1
• Ph meter has been calibrated
• No lactic was used to try and lower PH at any point in the mash process.
• Add O2 via Blichmann stone set-up (at rate of 1.5 Lpm) as the wort is being pumped from Kettle to FV
• I treated my mash & sparge water to get to Ca:130 / mg:11 / na: 34 / SO4: 320 / Cl: 79 — have had similar profiles before with hoppier pale ales and it’s been fine, nothing like what’s happening now, so I don't think it's the gypsum I'm adding to achieve those numbers.

Any suggestions?

 

[day_trippr]

"Let it be"?

That pH drop is caused by and benefits the yeast. Don't think you want to mess with that unless to make the drop happen quicker

Cheers!

 

[Anavrin215]

"Let it be"?

That pH drop is caused by and benefits the yeast. Don't think you want to mess with that unless to make the drop happen quicker

Cheers!

But the lower ph, the more acidic it becomes...especially in a pale ale, gives it an astringent / slightly acidic perception, which isn't right for the style.

Ideally the PH drops from say, 5.1 (post boil) to low 4s~ for a pale ale.

 

[couchsending]

if you hit 3.5 that quickly something is off… either it’s your meter or something else.

Bacteria can’t get there that quickly at ferm temps in the presence of any hops.

 

[day_trippr]

Ooops...I must've stopped reading before seeing that "3.5" pH bit.
I've never had a beer drop below 4 so don't have anything to help...

Cheers!

 

[Anavrin215]

if you hit 3.5 that quickly something is off… either it’s your meter or something else.

Bacteria can’t get there that quickly at ferm temps in the presence of any hops.

I can't think of what it could be. I typically calibrate my pH meter every other week, and then again before a brewday. I ordered new pH cal. solution, so will try that, but I've never had a pH reader issue like that in the past, and the fact the same exact thing happened after 2x identical brews with all same ingredients, I'm not sure it's the meter. Especially because the taste is inline with that lower pH reading.

I know you mentioned bacteria couldn't have gotten in that quickly, but I can't of what else it could be. Going back through my notes, I did ferm a kettle sour in this same FV back in Jan...but there've been 1-2 beers since, I thoroughly cleaned it (or so I thought).

I'm going to just boil all my rubber gaskets to ensure anything is killed there, and push 185+ water through tubing/riptide and FV before the next brew. Hopefully that does the trick because I really can't think of what else is causing the rapid drop.

 

[couchsending]

There’s no bacteria or really anything I’m aware of that can take a hopped wort to 3.5ph in 2 days at ferm temps in the presence of normal Sacch. Even the most aggressive, hop tolerant, lactic acid bacteria wouldn’t get that low at 68* in two days. You’d have to dump a pile of very hop tolerant bacteria in there and even then the yeast is out competing it. Philly sour could technically get to 3.5 in 2 days but not in the presence of any other yeast. It gets out competed instantly.

There’s something else happening.

You boiled the kettle sour after it soured right? If so there’s nothing to worry about there.

What pH meter do you have?

Kölsch yeast will get below 4.0 before going back up but I’ve never seen below 3.9 by any Sacch yeast I’ve used.

Are you seeing the pH creep back up at the end of fermentation?