ph during fermentation

Bigbre04

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ph is something that i recently started tracking, after reading @HighVoltageMan! 's post about it.

here is some data points that might help others.

I Brew a lot of my golden lager and my session IPA, here is the data that i collected after i started actively tracking ph.

Golden Lager 266: mash ph: 5.33/DnT -- Pre/OG: 5.39/5.34 -- OG: 11.0
Golden Lager 265: mash ph: 5.23/5.28 -- pre/OG: 5.38/5.36 -- OG: 12.3
Combined OG: 11.6 -- Temp SP 14C
-- day 2(second batch brew day): 11.9p 4.82ph
-- day 3-5 DNT -- Day 6: 6.3p 4.39ph
-- day 7(DRest raise pressure 10>15psi): 4.8p 4.35ph
--day 8(today): 3.4p 4.32ph

Golden Lager 255: mash ph: 5.3/5.31 -- Pre/OG: 11.6p, 5.43ph/12.1p, 5.38
Golden Lager 254: mash ph: 4.9(ph meter lost calibration)/Dnt -- Pre/OG: 10.7p, dnt/11.2, dnt
Combined OG: 11.65 -- temp sp 14c
--day 2(second brewday): 10.8p, 4.92ph
--day 3: 10.7p/4.73ph capped 10psi
--day 4-6: DNT
--day 7: 4.6p/4.46ph (DRest 10>15psi)
--day 8: 3.1p/dnt
--day 9: 2.7p/4.4ph
--day 10: 2.5p/4.39ph
--day 11: 2.5p/4.41ph crash 4.94%abv 79%atten
--day 12: carb/pack.

Golden Lager 249: mash ph: 5.2/5.38 -- Pre/OG: 11.1/11.6
Golden Lager 250: mash ph: DNT/dnt -- pre/OG: 11.6/11.7(added 3 gals h2o to adjust down preboil)
Combined OG:11.65 Finished on day 12-13 @ 79%atten and 4.95%abv
I was not taking ph as consistently at this point.

Session Juicy IPA 264: mash ph: 5.23/5.31 -- pre/og: 11.1p, 5.5ph/11.6p, 5.37ph
--day 2(dryhop): 3.1p/3.91ph(pre dryhop)
--day 3: 2.5p/4.05ph
--day 4-6: DNT
--day 7: 2.3p/4.09ph CRASH 5%abv 80%attenuation
--day 8: Carb/Pack

Session Juicy IPA 260: mash ph: 5.2/5.35 -- Pre/OG: 11.5p, dnt/11.6p, 5.35ph (messed the recipe up and overshot OG added water to drop from 11.9>11.6p
--day 2(DH): 2.6p/3.99ph
--day 3: 2.4p/4.09ph
--day 4: 2.4p/4.1ph
--day 5/6: DNT
--day 7: 2.2p/4.12ph CRASH 5.06%abv 81% Atten
--day 8: Carb/pack

Session Juicy IPA 252: Mash ph: DNT/5.4 -- pre/og: 11.3p, 5.47ph/11.65p, 5.4ph
--day 2(DH): 3.2p/3.9ph
--day 3: 2.5p/4.06ph
--day 4: 2.3p/4.1ph
--day5/6: DNT
--day 7: 2.3p/DNT Crash 80%atten 5.04%abv
--day 8: Carb/pack
 
Other beers:

Maibock 263: mash ph: 5.4ph/5.38ph -- Pre/OG: 14.7p, 5.43ph/ 15.4p, 5.33ph
--day 2: DNT
--day 3: 13.4p/dnt 10psi, 13.7c
--day 4: 12.1p/4.62ph
--day 5: 10.3p/4.53ph
--day 6: 8.1p/4.38ph
--day 7: 6.3p/4.31ph (d rest 10>15psi, 14>18c)
--day 8-10: DNT
--day 11: 3.5p/4.37ph
--day 12: 3.5p/4.39ph CRASH
--day 13(today): 3.4p/dnt CARB
--day 14(tomorrow): Pack

Black Lager 262: mash ph: 5.41/5.34 -- Pre/OG: 13.8p, 5.29ph/14.3p, 5.24ph(added 2.5gal of water to adjust OG down to 13.9)
--day 2/3: DNT
--day 4: 9.5p/4.37ph
--day 5: 5.3p/4.25ph(D Rest 14c>18c)
--day 6: 3.3p/4.28ph
--day 7: 3.2p/4.3ph
--day 8: 3.0p/4.3ph CRASH 6.03%abv 78% atten
--day12: carb/pack

Black Lager 253: mash ph: 5.25/5.34ph -- pre/OG: 13.1p,5.23ph/13.6, 5.14ph (ph meter was having a bad day)
--day 2: 13.1p/4.85ph
--day 3/4: DNT
--day 5: 4p/dnt
--day 6: 3.1p/4.19ph
--day 7: 3.1p/4.21ph Crash 5.8%abv 77%atten
--day 8: carb
--day 16: pack
 
WC IPA 258: mash ph: 5.37/5.28 -- Pre/OG: 15.2p, 5.54ph/16.0p, 5.49ph
--day 2: 15.4p/4.9ph
--day 3: 12.1p/4.5ph
--day4/5: DNT
--day 6(DH): 3.2p/4.26ph
--day 7: 3.1p/4.35ph
--day 8: 3.0p/4.3ph
--day 9: crash
--day 10: Carb/pack 7.34%abv 81% atten

WC IPA 251: mash ph: ph meter is wonky/5.4ph -- pre/og: 15.4p, dnt/16.0p, 5.35ph
--day 2: 15.0p/dnt
--day 3: 9.8p/4.28ph
--day4/5: dnt
--day 6(DH): 3.1p/4.2ph
--day 7: ph4.27
--day 8: ph 4.3 COOL
--day 9: CRASH
--day 10: carb/pack 7.29%abv 81%atten
 
well I don't see any surprises
you didn't mention doing any adjustments post boil so I assume you didnt
thanks for doing the work so I don't have to
 
basically you are confirming that a mash of 5.3 pH ends at 4.3 pH which is right in the appropriate zone
 
I notice your lager s are landing @ 4.3, but the hazy landed about 4.1 or so. What yeast was that? It must be an English variety.

Thanks for posting your results, always interesting! At least to me.
 
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basically you are confirming that a mash of 5.3 pH ends at 4.3 pH which is right in the appropriate zone
Yes and no. The pitch pH (AKA knock out) is a little high at 5.3, but despite that the yeast hit 4.3 on the finish. This is strain dependent, so if a Kolsch yeast were used, this finish pH would be too high. But for a lager yeast. it's in the ball park. The other note is that mash pH almost never translates to pitch or "knock out" pH without some kind of post mash pH adjustment.

A lot of brewers, including myself, will shoot for a pitch pH of 5.1, this makes it easier for the yeast to hit it's normal range on finish. This also will increase the overall acid in the beer. Since most brewers use lactic or phosphoric acid, there is residual acid left intact because they are weak acids and they don't completely disassociate like strong acids. Those acids can act to produce a smoother, snappier finish and add to the overall quality of beer when done correctly.
 
Yes and no. The pitch pH (AKA knock out) is a little high at 5.3, but despite that the yeast hit 4.3 on the finish. This is strain dependent, so if a Kolsch yeast were used, this finish pH would be too high. But for a lager yeast. it's in the ball park. The other note is that mash pH almost never translates to pitch or "knock out" pH without some kind of post mash pH adjustment.
I have numbers on my kolsch yeast. ill type them out later today or tomorrow.
A lot of brewers, including myself, will shoot for a pitch pH of 5.1, this makes it easier for the yeast to hit it's normal range on finish. This also will increase the overall acid in the beer. Since most brewers use lactic or phosphoric acid, there is residual acid left intact because they are weak acids and they don't completely disassociate like strong acids. Those acids can act to produce a smoother, snappier finish and add to the overall quality of beer when done correctly.
my brewhouse is dumb, I have to mash in twice which adds to my overall day, but also very much complicates the process. BUT it does allow me some flexibility if i overshoot acid on the first mash.

So i should be shooting for 5.1 on knockout? i can start pitching acid at whirlpool to aim for that, no problem.

I use Phos @ 75%.
I notice your lager s are landing @ 4.3, but the hazy landed about 4.1 or so. What yeast was that? It must be an English variety.
I use Voss for my hazies! it is awesome. they stay hazy for the entire "shelf life" of the beer which is generally 90 days. not that i have any beer last that long on draft, but i have little doubt that it will last.
Thanks for posting your results, always interesting! At least to me.
The golden lager is using Apex Augustinian yeast, pressure fermented at 14c

The session IPA uses Apex Voss, knocked at 100f, Tank is set to 40c

The Maibock is Apex Munich lager, pressure fermented at 14c.

Black lager is Munich Lager yeast, not pressure fermented at 14c.

WC IPA is Apex San Diego(chico) at 68f

All are pitched at 250g/2bbls(finished so roughly 76gals to the fermenter) which is fairly heavy, especially for the SD and Voss. I push O2 on all of the fresh pitch batches. All get 20 grams of Yeast X and 10g of Kick Keisielgerrrrr(whirlflock).

Golden Lager is a double batch split between 2 days.

Fermenters are 3.5bbl stiencraft(chinese knockoff) tanks. that work fine.


My fermentation times, attenuation, and OGs are pretty consistent. alot of the variation is from trying new grain types, adding enzymes, messing with my mill, or milling when it is super windy outside(i have started noting that since it actually changes my OG)
 
Consistency is key to repeatably great beer. Careful notes are key to consistency.
 
So i should be shooting for 5.1 on knockout? i can start pitching acid at whirlpool to aim for that, no problem.

I use Phos @ 75%.
I have been adjust boil/pitch/knockout pH for years since I saw an interview with John Kimmich (The Alchemist) who mentioned he would never pitch yeast in wort above 5.2 pH and that he was okay with pitching at 5.1 pH, but for their beers he preferred 5.2. I started doing it right away and it helped with consistency in beers, especially with the finish and bitterness.

Since then I bought Kunze's German brewing book and in there it states that a pH of 5.1 at pitch was optimal for yeast health and beer quality. The idea behind it is that each strain of yeast will drop it's nominal finish pH provided the wort pH isn't too high. The yeast needs this to reduce the amount of energy or effort needed to bring in nutrients across the cell's outside membrane. By reducing the pH of the wort and increasing internal pH of the cell, this reduces the energy expended by the cell and increases yeast health. If the pitch pH is too high, the yeast may not be able to drop the pH of the beer causing a lot of different problems with the beer quality.

The best pH for yeast according to Bamforth is 4.7, which he goes on to say that would make a terrible beer. 5.1 is really a compromise between yeast health and beer quality. The yeast drop the pH of the beer by excreting hydrogen ions and consuming the available FAN in the wort. The FAN acts as a buffer to keep the pH high and the reduction of FAN allows the pH to drop.

There are two views on when to adjust the pH of the knock out. One is near the end of the boil or in the whirlpool. The higher pH during boil drives off DMS quicker and increases or speeds up protein coagulation and increases the Maillard reaction (color development). The other is to acidify pre-boil, which slows the driving off of DMS and slows protein coagulation, but reduces the Maillard reaction (low or no color development). Most pro's adjust post boil because the boil time could potentially be reduced and the risk of DMS is too high. So for you, adjusted during the whirlpool makes the most sense to me. I, on the other hand, adjust pre-boil because I'm a homebrewer and an extra 15-30 minutes of boil is no big deal. The other reason I do it pre-boil is because I'm absent minded and will completely forget to do it and I like really light colored, flavorful beer.

As you watch your overall finish pH, you will get used to what you should and shouldn't see. Brewers often use the finish pH as an indication of yeast health, so if you re-pitch it could be useful.

Sorry to be so long winded again, but the $h!+ fascinates me.
 
I have been adjust boil/pitch/knockout pH for years since I saw an interview with John Kimmich (The Alchemist) who mentioned he would never pitch yeast in wort above 5.2 pH and that he was okay with pitching at 5.1 pH, but for their beers he preferred 5.2. I started doing it right away and it helped with consistency in beers, especially with the finish and bitterness.

Since then I bought Kunze's German brewing book and in there it states that a pH of 5.1 at pitch was optimal for yeast health and beer quality. The idea behind it is that each strain of yeast will drop it's nominal finish pH provided the wort pH isn't too high. The yeast needs this to reduce the amount of energy or effort needed to bring in nutrients across the cell's outside membrane. By reducing the pH of the wort and increasing internal pH of the cell, this reduces the energy expended by the cell and increases yeast health. If the pitch pH is too high, the yeast may not be able to drop the pH of the beer causing a lot of different problems with the beer quality.

The best pH for yeast according to Bamforth is 4.7, which he goes on to say that would make a terrible beer. 5.1 is really a compromise between yeast health and beer quality. The yeast drop the pH of the beer by excreting hydrogen ions and consuming the available FAN in the wort. The FAN acts as a buffer to keep the pH high and the reduction of FAN allows the pH to drop.

There are two views on when to adjust the pH of the knock out. One is near the end of the boil or in the whirlpool. The higher pH during boil drives off DMS quicker and increases or speeds up protein coagulation and increases the Maillard reaction (color development). The other is to acidify pre-boil, which slows the driving off of DMS and slows protein coagulation, but reduces the Maillard reaction (low or no color development). Most pro's adjust post boil because the boil time could potentially be reduced and the risk of DMS is too high. So for you, adjusted during the whirlpool makes the most sense to me. I, on the other hand, adjust pre-boil because I'm a homebrewer and an extra 15-30 minutes of boil is no big deal. The other reason I do it pre-boil is because I'm absent minded and will completely forget to do it and I like really light colored, flavorful beer.

As you watch your overall finish pH, you will get used to what you should and shouldn't see. Brewers often use the finish pH as an indication of yeast health, so if you re-pitch it could be useful.

Sorry to be so long winded again, but the $h!+ fascinates me.
Hey totally appreciate it.

My post boil was 5.34 again yesturday. added 10 ml 75% phos during whirlpool and got it down to 5.14ph so i call that a victory.

missed my OG by a fair amount, but i think that is a combo of several things. Seeing as my eff was set to 90% and i hit 84% and was able to adjust my grav by adding more dextrose.

i need to double check my ph meter today, but i suspect that the culprit was wind and potentially me fucking up the grain measures. should be a good beer either way.

Now i am battling head retention. I think the Apex Multizyme that i have started adding is zapping my head retention. so i am starting to add back dextin malts to my recipes hoping that they can help with head retention. IF that doesnt work i may switch back to beta glucanase and live with the slightly lower brew house eff.
 
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Wow. All of this is very helpful and at the same time a little overwhelming. :). I just started tracking PH myself. My PH meter was also having a bad day yesterday. My first check at 15 mins in the mash was 2.5 (wth 2.5?). Ended mash with 6.0 and added 1 mil of Lactic 88% pre-boil and ended at 5.4. Thanks for all of these details.
 
So my IPA where i adjusted the starting pH down to 5.14 is cooling tomorrow.

I dryhopped it yesturday. it was at:

Day 5: 2.7p, 19.4c, 4.14ph, 6.86%abv, 82% atten
Day 6(today): 2.5p, 20.1c, 4.23ph, 6.96%ABV, 83% atten

this is the highest attenuation that i have seen(i think) for chico. Makes me wonder if that was from the ph adjustment???? It cools tomorrow down to 60f and crashes thursday. ill carb and pack it on friday(day 9).

It is REALLY GOOD. I am very happy with the hops and recipe, even though the brewday was a little rough.

recipe:
https://www.brewersfriend.com/homebrew/recipe/embed/1629928
 
The pitch pH certainly doesn’t hurt your attenuation and may even have helped, but attenuation is a really a complicated subject and one detail helps but may not be the sole reason.

I’m glad the beer turned out so well!
 
The pitch pH certainly doesn’t hurt your attenuation and may even have helped, but attenuation is a really a complicated subject and one detail helps but may not be the sole reason.

I’m glad the beer turned out so well!
strangely enough it is still dropping. down to 2.4p 85% atten and 7.06abv pH went up to 4.37. i went through my notes and the last 3 batches that were in that tank were all lager yeast and all had normal attenuation/no problems so i dont think it was voss sneaking in or anything. i am guessing that my hops have some hop creep going on. it is surely not bad. it tastes awesome and im cooling today, crashing tomorrow, and carbing/packing on friday.

i havent really seen alot of hop creep with this recipe so far so maybe citra/krush/simcoe have some increased hop creep potential compared to my previous hop bill?
 
If your pH is truly rising, it could be a sign of yeast autolysis. But I doubt that’s the case. That pH is really nice after dry hopping. It’s not uncommon for dry hopping to raise pH by .2-.3 pH. 4.4 or lower is really good finish for a dry hopped IPA.
 
If your pH is truly rising, it could be a sign of yeast autolysis. But I doubt that’s the case. That pH is really nice after dry hopping. It’s not uncommon for dry hopping to raise pH by .2-.3 pH. 4.4 or lower is really good finish for a dry hopped IPA.
it has def risen, autolysis is unlikely considering that we are only on day 8.

i am actually glad that i crashed it last night before i left. My previous ipa just kicked so it is going right on draft. i had planned on carbing it and letting it settle and packing it tomorrow. but that is not how things worked out lol.
 

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