Mash pH meter

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And you an engineer what chance the rest of us :laugh8:
I know… I know - oh, the shame of it LoL
While on the subject, a point that’s often forgotten when people measure the pH of the mash is that pH depends on temperature. So the pH of a sample measured at mash temp probably reads about 0.2-0.3 pH units lower than the same sample cooled to 25°C (this applies whether you‘re using strips or a meter). If you’re trying to hit the ‘right’ pH, bear in mind that figures quoted in the literature will typically be for a cooled sample.
 
I know… I know - oh, the shame of it LoL
While on the subject, a point that’s often forgotten when people measure the pH of the mash is that pH depends on temperature. So the pH of a sample measured at mash temp probably reads about 0.2-0.3 pH units lower than the same sample cooled to 25°C (this applies whether you‘re using strips or a meter). If you’re trying to hit the ‘right’ pH, bear in mind that figures quoted in the literature will typically be for a cooled sample.
I always cool mine down to room temp as I do not trust the ATC on the PH meter anyway
 
Its not that they may not work but I do them at the temp that they should be done at, I do the same with my Refractometer too Tess always at room temp also my Hydrometer readings too.
I have read about issues so I take the issue away its just a matter of cooling in the fridge for a while
 
I always cool mine down to room temp as I do not trust the ATC on the PH meter anyway
Another common misconception actually: I'm given to understand that ATC does not make your meter report what the pH of a cooled sample will be... all it does is ensure the meter provides an accurate reading at a temperature that's not 25ºC - but "accurate" in this case still means a different value of pH.

TLDR: if you want to measure your mash pH then test a cooled sample.
 
ATC does work, it's just that it doesn't do what people tend to think it does :-)

Perhaps they ought to make it more clear if that is indeed the case. Otherwise without in-depth technical knowledge, we're all being conned.

As I understood it before this conversation, Automatic Temperature Compensation does just that, it compensates, and adjusts your reading to what it would have been at the 'correct' temperature. I see it as the same as going onto Brewfather and using the temperature adjustment calculators for a hydrometer, for example.
 
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Perhaps they ought to make it more clear if that is indeed the case. Otherwise without in-depth technical knowledge, we're all being conned.
ATC on the pH meter works as designed. It's an entirely separate issue to measuring mash pH at 20°c.

Mash pH changes with temperature and whilst we mash at c66°c, all the science and guidence is based on lab work where the practice is to cool the sample to standard temperature of 20°C to make a measurement.
 
On here, I find it's a case of critically evaluating all the different opinions you could possibly get on a particular question. I tend to use my own brain to work things out instead of relying on other people, because contrary to popular belief, I do have one. It's always a good idea to separate the potential guessing and hearsay from actual facts.

I will carry on using my meter in the way I always have done, because it works for me. athumb..
 
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Forgive the stupid question, but what's the cost/benefit of spending a lot on a pH meter?

When I first started AG brewing I used to test the pH with papers and lower my water pH to achieve the magic 5.3 From what I could tell, all I got was a slightly better mash efficiency i.e. I saved a few pence in grain cost. Eventually I stopped doing it when I ran out of pH papers. Am I missing something?
 
A quick lift from the tinterweb

Having the correct pH will:
- Improve enzyme activity during the mash. This will increase conversion of starches to fermentable sugars
- Lower pH in the finished wort. Improving yeast health during fermentation and inhibiting bacteria growth.
- Improved hop extraction rates in the boil and giving smoother bitterness
- Better protein and polyphenol precipitation both during the cold break and post fermentation
- Improved clarity in the finished beer with reduced chill haze.
- Improved flavour and clarity stability as the beer ages.
 
On here, I find it's a case of critically evaluating all the different opinions you could possibly get on a particular question. I tend to use my own brain to work things out instead of relying on other people, because contrary to popular belief, I do have one. It's always a good idea to separate the potential guessing and hearsay from actual facts.

I will carry on using my meter in the way I always have done, because it works for me. athumb..
Ask 10 homebrewers a question and you'll get 10 different answers 🤣. It's a case of doing what works for you. Some don't measure pH and are happy, some use paper strips and are happy, some use cheap meters and are happy and some use expensive meters and are happy.
 

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