Spike Brewing 12.5 Conical Fermenter Giveaway!

Home Brew Forums > Home Brewing Beer > Brew Science > Mash pH measurement

Reply
 
LinkBack Thread Tools
Old 01-16-2013, 06:50 AM   #1
nukebrewer
Brew the brew!
HBT_LIFETIMESUPPORTER.png
Feedback Score: 10 reviews
 
nukebrewer's Avatar
Recipes 
 
Join Date: Oct 2008
Location: Groton, CT
Posts: 4,693
Liked 2533 Times on 1486 Posts
Likes Given: 5710

Default Mash pH measurement

There's apparently a conflict regarding the recommended way to measure your mash pH. I've seen it mentioned here in one thread or another that your mash pH should be measured at room temperature, which is the method I am accustomed to since I take samples of ~500 F nuclear propulsion plant water but measure it at 25 C. In direct opposition to this Gordon Strong's Brewing Better Beer in which he says that you should measure your mash temperature at mash temp (page 34, first full paragraph, second sentence). I just want to get this cleared up so I make sure I am performing my measurements correctly.

__________________

The only thing more asinine than stupid rules is the enforcement of rules simply because they are the rules.

Inhopsicated: A Beer Blog

Inhopsicated on Twitter

nukebrewer is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 12:20 PM   #2
ajdelange
Senior Member
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2010
Location: McLean/Ogden, Virginia/Quebec
Posts: 5,803
Liked 563 Times on 464 Posts
Likes Given: 15

Default

This is one of the very few instances in which I disagree with Gordon. The reasons for doing it at room temperature are clear not the least of which is extension of the life of your electrode. Beyond that going back to the early days samples had to be transported to the laboratory for measurement during which time they cooled and thus pH values reported in the literature are, unless otherwise stated, laboratory temperature pH's. DeClerck specifically mentions that in his book all reported pH values are lab temp. If it's good enough for him it's good enough for me.

__________________
ajdelange is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 12:44 PM   #3
mabrungard
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2011
Location: Carmel, IN
Posts: 2,686
Liked 181 Times on 158 Posts
Likes Given: 24

Default

Unfortunately, Gordon was not very familiar with this subject when he authored that book. As AJ reiterates, a brewer is far better off measuring mash pH at room temperature for multiple reasons. More over, the pH offset due to the drop from mash temperature to room temperature is relatively consistent. Therefore, it is possible to properly measure pH at room temperature and estimate the actual pH in the hot mash.

But standardizing on a room temperature mash pH measurement is the direction that I and many others have taken.

__________________

Martin B
Carmel, IN
BJCP National
Foam Blowers of Indiana (FBI)

Brewing Water Information at:
https://sites.google.com/site/brunwater/

Like Bru'n Water on Facebook for occasional discussions on brewing water and Bru'n Water

mabrungard is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 03:17 PM   #4
Hermit
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2009
Location: Alternate Universe
Posts: 2,226
Liked 61 Times on 55 Posts
Likes Given: 10

Default

Quote:
Originally Posted by mabrungard View Post
But standardizing on a room temperature mash pH measurement is the direction that I and many others have taken.
This is bottom line. We want a workable, repeatable process to work from.
__________________
Hermit is online now
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 05:28 PM   #5
nukebrewer
Brew the brew!
HBT_LIFETIMESUPPORTER.png
Feedback Score: 10 reviews
 
nukebrewer's Avatar
Recipes 
 
Join Date: Oct 2008
Location: Groton, CT
Posts: 4,693
Liked 2533 Times on 1486 Posts
Likes Given: 5710

Default

Thanks for the clarification. Cheers!

__________________

The only thing more asinine than stupid rules is the enforcement of rules simply because they are the rules.

Inhopsicated: A Beer Blog

Inhopsicated on Twitter

nukebrewer is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 05:31 PM   #6
kombat
HBT_SUPPORTER.png
Feedback Score: 1 reviews
Recipes 
 
Join Date: Oct 2009
Location: Ottawa, Ontario, Canada
Posts: 2,638
Liked 674 Times on 436 Posts
Likes Given: 602

Default

Quote:
Originally Posted by nukebrewer View Post
I take samples of ~500 F nuclear propulsion plant water but measure it at 25 C.
Minor nitpick: You cannot have water at 500° F unless it's under tremendous pressure. Water, of course, turns to steam at 212° F. At normal atmospheric pressure, that's the hottest you can have water, no matter how much heat you apply. Applying more heat just turns it into steam faster, but the water itself can only ever be 212° F.
__________________
kombat is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 05:53 PM   #7
ajdelange
Senior Member
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2010
Location: McLean/Ogden, Virginia/Quebec
Posts: 5,803
Liked 563 Times on 464 Posts
Likes Given: 15

Default

Of course I don't know but I'm guessing that some pretty hefty pressures might be found in a nuclear propulsion plant.

__________________
ajdelange is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 06:20 PM   #8
ingchr1
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
ingchr1's Avatar
Recipes 
 
Join Date: Aug 2009
Location: Orange County NY
Posts: 327
Liked 33 Times on 32 Posts
Likes Given: 8

Default

Quote:
Originally Posted by ajdelange View Post
Of course I don't know but I'm guessing that some pretty hefty pressures might be found in a nuclear propulsion plant.
~1800psi
__________________

Chris

ingchr1 is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 06:21 PM   #9
nukebrewer
Brew the brew!
HBT_LIFETIMESUPPORTER.png
Feedback Score: 10 reviews
 
nukebrewer's Avatar
Recipes 
 
Join Date: Oct 2008
Location: Groton, CT
Posts: 4,693
Liked 2533 Times on 1486 Posts
Likes Given: 5710

Default

Quote:
Originally Posted by kombat View Post
Minor nitpick: You cannot have water at 500° F unless it's under tremendous pressure. Water, of course, turns to steam at 212° F. At normal atmospheric pressure, that's the hottest you can have water, no matter how much heat you apply. Applying more heat just turns it into steam faster, but the water itself can only ever be 212° F.
Quote:
Originally Posted by ajdelange View Post
Of course I don't know but I'm guessing that some pretty hefty pressures might be found in a nuclear propulsion plant.
You are indeed correct, AJ. I'm not at liberty to divulge the exact pressure, but it's up there. High enough to keep it from flashing to steam, at least. Also, the pressure needed to keep it from flashing at those temperatures isn't as high as you might think.
__________________

The only thing more asinine than stupid rules is the enforcement of rules simply because they are the rules.

Inhopsicated: A Beer Blog

Inhopsicated on Twitter

nukebrewer is offline
 
Reply With Quote Quick reply to this message
Old 01-16-2013, 06:24 PM   #10
nukebrewer
Brew the brew!
HBT_LIFETIMESUPPORTER.png
Feedback Score: 10 reviews
 
nukebrewer's Avatar
Recipes 
 
Join Date: Oct 2008
Location: Groton, CT
Posts: 4,693
Liked 2533 Times on 1486 Posts
Likes Given: 5710

Default

Quote:
Originally Posted by ingchr1 View Post
~1800psi
Shhh! That's a government nuclear secret!
__________________

The only thing more asinine than stupid rules is the enforcement of rules simply because they are the rules.

Inhopsicated: A Beer Blog

Inhopsicated on Twitter

nukebrewer is offline
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Need a measurement please fury556 Equipment/Sanitation 3 12-28-2012 03:07 AM
BIAB Mash Temp Measurement epateddy General Techniques 22 09-16-2012 02:13 PM
Confused about Mash Ph measurement akinsgre All Grain & Partial Mash Brewing 3 11-21-2011 08:18 PM
AG Mash Temp measurement question - WoofdogABC All Grain & Partial Mash Brewing 1 09-02-2011 01:20 AM
Mash ph measurement problem? BigdogMark All Grain & Partial Mash Brewing 2 10-10-2009 12:19 AM



Newest Threads