Author Topic: Can I predict finial beer PH?  (Read 690 times)

Offline quattlebaum

  • Brewer
  • ****
  • Posts: 355
    • View Profile
    • Wildhops
Can I predict finial beer PH?
« on: July 01, 2014, 08:32:34 PM »
This is a complicated ? And I know there are many variables in this ? But how and do you predict the finial beer PH?   

Offline morticaixavier

  • I must live here
  • **********
  • Posts: 7516
  • Underhill VT
    • View Profile
    • The Best Artist in the WORLD!!!!!
Re: Can I predict finial beer PH?
« Reply #1 on: July 01, 2014, 08:36:50 PM »
It has a lot to do with the yeast and fermentation conditions. I'm not sure how you would go about predicting it. I suppose you could start by taking measurements with the same grist and fermentation conditions and vary the yeast among your favorite few strains. that should help you narrow down your average yeast derived change. then you can do the same for grains, water chemistry, and fermentation conditions.

After you have all the data you can begin analyzing it for correlations, build some predictive models, and extrapolate a set of rules to calculate the final beer pH.

Then I guess you sit back and enjoy basking in the warm glow of your fellow homebrewers awe and appreciation. ;D
"Creativity is the residue of wasted time"
-A Einstein

"errors are [...] the portals of discovery"
- J Joyce

Offline quattlebaum

  • Brewer
  • ****
  • Posts: 355
    • View Profile
    • Wildhops
Re: Can I predict finial beer PH?
« Reply #2 on: July 01, 2014, 08:49:06 PM »
it has just been frustrating lately because most of my beers are low. Just did an IPA and use chico and was shocked that it dropped 1.6pts.

Recipe: Blind Pig #2
Brewer: Quattlebaum
Asst Brewer:
Style: American IPA
TYPE: All Grain
Taste: (30.0)

Recipe Specifications
--------------------------
Boil Size: 5.66 gal
Post Boil Volume: 4.16 gal
Batch Size (fermenter): 3.50 gal   
Bottling Volume: 3.25 gal
Estimated OG: 1.058 SG
Estimated Color: 5.5 SRM
Estimated IBU: 62.0 IBUs
Brewhouse Efficiency: 73.00 %
Est Mash Efficiency: 83.4 %
Boil Time: 90 Minutes

Ingredients:
------------
Amt                   Name                                     Type          #        %/IBU         
7 lbs 1.5 oz          Pale Malt (2 Row) US (2.0 SRM)           Grain         1        93.0 %       
4.9 oz                Caramel/Crystal Malt - 40L (40.0 SRM)    Grain         2        4.0 %         
3.7 oz                Carafoam (Weyermann) (2.0 SRM)           Grain         3        3.0 %         
0.32 oz               Chinook [14.20 %] - Boil 90.0 min        Hop           4        24.7 IBUs     
0.19 oz               Columbus (Tomahawk) [15.20 %] - Boil 90. Hop           5        15.7 IBUs     
0.25 oz               Amarillo Gold [10.30 %] - Boil 30.0 min  Hop           6        10.1 IBUs     
0.37 oz               Centennial [9.60 %] - Steep/Whirlpool  1 Hop           7        3.3 IBUs     
0.35 oz               Simcoe [12.20 %] - Steep/Whirlpool  10.0 Hop           8        3.9 IBUs     
0.29 oz               Cascade [7.20 %] - Steep/Whirlpool  10.0 Hop           9        1.9 IBUs     
0.25 oz               Amarillo Gold [10.30 %] - Steep/Whirlpoo Hop           10       2.4 IBUs     
1.0 pkg               American Ale (Wyeast Labs #1056) [124.21 Yeast         11       -             
0.35 oz               Amarillo Gold [10.30 %] - Dry Hop 7.0 Da Hop           12       0.0 IBUs     
0.35 oz               Cascade [7.20 %] - Dry Hop 7.0 Days      Hop           13       0.0 IBUs     
0.35 oz               Columbus (Tomahawk) [15.20 %] - Dry Hop  Hop           14       0.0 IBUs     


Mash Schedule: (208) Single Infusion, Medium Body, No Mash Out, Fly
Total Grain Weight: 7 lbs 10.0 oz
----------------------------
Name              Description                             Step Temperat Step Time     
Mash In           Add 3.34 gal of water at 164.5 F        150.0 F       60 min       

Sparge: Fly sparge with 3.24 gal water at 168.0 F
Notes:
------
Water:  Ca 87, Mg 3, Na 10, Sulfate 154, Cl 31, Bicarb 47, Alkalinity 39, RA -25 Mash ph 5.44 post boil PH 5.4 all at room temp. pitched a recommended yeast starter from Ez yeast cal. Finial PH 4 ya 4!

Offline Steve in TX

  • Official Poobah of No Life.
  • *
  • Posts: 3299
    • View Profile
Re: Can I predict finial beer PH?
« Reply #3 on: July 02, 2014, 05:23:24 AM »
As far as I know 4-4.5 is pretty normal for final beer ph. I'm sure somebody with a science background would know for sure.

Offline Jeff M

  • Brewmaster
  • *****
  • Posts: 821
  • Currently upgrading to Brewery 3.0
    • View Profile
Re: Can I predict finial beer PH?
« Reply #4 on: July 02, 2014, 07:06:27 AM »
The pH of beer goes down during fermentation.  Its one of the qualities of beer that allowed beer to be drinkable when the local water was not.  I believe i read a few paragraphs about this in the yeast book, but im not sure exactly.

Jeff
Granite Coast Brewing Company.
Building a clone of The Electric Brewery to use as a pilot system for new recipes!

Offline quattlebaum

  • Brewer
  • ****
  • Posts: 355
    • View Profile
    • Wildhops
Re: Can I predict finial beer PH?
« Reply #5 on: July 02, 2014, 07:51:35 AM »
I have been attempting to hit 4.4 to see what chareteristcs i will get. It seems that when my PH of my IPAs are lower say under 4.2 that the hop profile seems less promenate and less characteristic of a true american IPA more like a pale ale characture. Its stiil a good beer but a little "muted" or muttled on the hops for an IPA ill inter it in a local comp to see what some of the judges say

Offline morticaixavier

  • I must live here
  • **********
  • Posts: 7516
  • Underhill VT
    • View Profile
    • The Best Artist in the WORLD!!!!!
Re: Can I predict finial beer PH?
« Reply #6 on: July 02, 2014, 08:03:22 AM »
I have been attempting to hit 4.4 to see what chareteristcs i will get. It seems that when my PH of my IPAs are lower say under 4.2 that the hop profile seems less promenate and less characteristic of a true american IPA more like a pale ale characture. Its stiil a good beer but a little "muted" or muttled on the hops for an IPA ill inter it in a local comp to see what some of the judges say

have you considered directly altering the pH of the finished beer? pickling lime would seem ideal for that experiment. you would obviously want to dilute it significantly so you could add an easily measured amount to a glass of beer
"Creativity is the residue of wasted time"
-A Einstein

"errors are [...] the portals of discovery"
- J Joyce

Offline Jeff M

  • Brewmaster
  • *****
  • Posts: 821
  • Currently upgrading to Brewery 3.0
    • View Profile
Re: Can I predict finial beer PH?
« Reply #7 on: July 02, 2014, 08:26:49 AM »
IF you raise the prefermented wort by .2 (say from 5.2 to 5.4)  it should reflect in the finished product, correct?
Granite Coast Brewing Company.
Building a clone of The Electric Brewery to use as a pilot system for new recipes!

Offline HoosierBrew

  • Official Poobah of No Life.
  • *
  • Posts: 6801
  • Indianapolis,IN
    • View Profile
Re: Can I predict finial beer PH?
« Reply #8 on: July 02, 2014, 08:36:42 AM »
Still trying to get my head around it - if you nail your mash pH pretty spot on, shouldn't good pH carry through the process ?    ???
Jon H.

Offline quattlebaum

  • Brewer
  • ****
  • Posts: 355
    • View Profile
    • Wildhops
Re: Can I predict finial beer PH?
« Reply #9 on: July 02, 2014, 08:50:38 AM »
IF you raise the prefermented wort by .2 (say from 5.2 to 5.4)  it should reflect in the finished product, correct?
Have done this but does not make a difference. I think i need to raise my RA and Alkalinity  a bit and maybe that will help. There are some many varabiles i would like to get to a point that my PH only drops 1 point post boil consistently but i dont know if thats feasible. I think i need to stick to the same yeast, pitch the same amount and attempt to use the same maltsters grain.
I do like the idea of maybe adding some minerals to alter the PH a bit to maybe make it a bit "harsher" for style but hell ill just drink this keg and brew it again :) 

Offline Jeff M

  • Brewmaster
  • *****
  • Posts: 821
  • Currently upgrading to Brewery 3.0
    • View Profile
Re: Can I predict finial beer PH?
« Reply #10 on: July 02, 2014, 08:54:03 AM »
Contact Martin.  He will help you get to the bottom of this.
Granite Coast Brewing Company.
Building a clone of The Electric Brewery to use as a pilot system for new recipes!

Offline quattlebaum

  • Brewer
  • ****
  • Posts: 355
    • View Profile
    • Wildhops
Re: Can I predict finial beer PH?
« Reply #11 on: July 02, 2014, 08:56:20 AM »
Still trying to get my head around it - if you nail your mash pH pretty spot on, shouldn't good pH carry through the process ?    ???

From my understanding No. Mash PH is such a small part of it. Mash PH is mainly for conversion sakes however i do feel that it does have a small part. Things such as pitch rate and type of yeast and the Alkalinity and perhaps the residual Alkalinity have the bigest role.  Challenging it is.   

Offline Jeff M

  • Brewmaster
  • *****
  • Posts: 821
  • Currently upgrading to Brewery 3.0
    • View Profile
Re: Can I predict finial beer PH?
« Reply #12 on: July 02, 2014, 08:58:10 AM »
Have you thought about carbonating less?  Carbonic Acid should contribute to pH, no?
Granite Coast Brewing Company.
Building a clone of The Electric Brewery to use as a pilot system for new recipes!

Offline erockrph

  • Official Poobah of No Life.
  • *
  • Posts: 4309
  • Chepachet, RI
    • View Profile
    • The Hop WHisperer
Re: Can I predict finial beer PH?
« Reply #13 on: July 02, 2014, 09:19:21 AM »
Once fermentation happens I think all bets are off. The yeast drives the conditions from that point on.

What makes pH adjustments so complicated is that beer is a complex solution. To make a truly accurate prediction of pH adjustments you would need to know the concentrations and pKa's of every ion in solution. Or you can adjust in small increments and measure the results.

What a lot of people have a hard time wrapping their head around is that you aren't actually adjusting pH directly. You are adjusting the disassociation of all the compounds that contribute to the buffering capacity of the solution. The pH is essentially a side effect of that change.

You could have two different solutions at the same pH, then add the same amount of acid to them. One solution might drop several pH points, while the other might barely go down at all. It depends greatly on the composition of those two solutions.
Eric B.

Finally got around to starting a homebrewing blog: The Hop Whisperer

Offline HoosierBrew

  • Official Poobah of No Life.
  • *
  • Posts: 6801
  • Indianapolis,IN
    • View Profile
Re: Can I predict finial beer PH?
« Reply #14 on: July 02, 2014, 09:30:12 AM »
Reworded :  Sounds like you could easily make it worse and not better. Maybe not. Obviously I have never done this, not very sure I would.
Jon H.