pH calibration with wort temps on Milwaukee M102

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Gustatorian

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Recently purchased the Milwaukee M102. Anybody know if pH needs to be adjusted for wort temps. It seems intuitive that the company would have the probe adjust it, since it measure temp as well. Just wanted to make sure...
 
Readings should always be taken at 25C (77F). Unless a temperature is given, pH numbers are always assumed to be at 25C. If you take the reading hot, it will be a little lower.

Hot solutions are more acidic than room temperature solutions. ATC does not compensate for that.

ATC compensates for errors from the probe. It’s designed for 25C, so the computer applies a little fudge factor when it isn’t. Supposedly this is way better than twisting a little knob, like on the MW101 to set the sample temp. Guess which one I have.

If the sample is not at 25C, it’s actual pH will be different. Plus they say hot readings shorten the life of the electrode.
 
Readings should always be taken at 25C (77F). Unless a temperature is given, pH numbers are always assumed to be at 25C. If you take the reading hot, it will be a little lower.

Hot solutions are more acidic than room temperature solutions. ATC does not compensate for that.

ATC compensates for errors from the probe. It’s designed for 25C, so the computer applies a little fudge factor when it isn’t. Supposedly this is way better than twisting a little knob, like on the MW101 to set the sample temp. Guess which one I have.

If the sample is not at 25C, it’s actual pH will be different. Plus they say hot readings shorten the life of the electrode.

So how do you go about measuring mash PH? And when? I guess I could cold crash a sample of the mash, but when should I check the pH to assure a final reading and still have time to adjust minerals if need be? Thanks!
 
So how do you go about measuring mash PH? And when? I guess I could cold crash a sample of the mash, but when should I check the pH to assure a final reading and still have time to adjust minerals if need be? Thanks!


Grab a shot glass and fill a sample. Throw it in the freezer. Takes just a few min.
 
So how do you go about measuring mash PH? And when? I guess I could cold crash a sample of the mash, but when should I check the pH to assure a final reading and still have time to adjust minerals if need be? Thanks!

Take the sample, as it's only an ounce or two and put it in an ice bath quickly. When it's 72 (mine is 72), take the reading. It's just a minute or two to cool.

When you read "mash temp of 5.3-5.5", that is assuming room temperature readings.
 
Readings should always be taken at 25C (77F). Unless a temperature is given, pH numbers are always assumed to be at 25C. If you take the reading hot, it will be a little lower.



Hot solutions are more acidic than room temperature solutions. ATC does not compensate for that.



ATC compensates for errors from the probe. It’s designed for 25C, so the computer applies a little fudge factor when it isn’t. Supposedly this is way better than twisting a little knob, like on the MW101 to set the sample temp. Guess which one I have.



If the sample is not at 25C, it’s actual pH will be different. Plus they say hot readings shorten the life of the electrode.


Really don't want to argue, but there are ph transmitters with true ATC at process temp. We use them all the time at temperatures above 200f and they are just as accurate as taking the sample at STP. I use GLI transmitters.
 
For temperature-rated probes, there is only minor probe life loss when operating at a consistent high temperature. There are plenty of industrial processes that need pH measurement at high temperature. However, those users have calibrated their probe measurements with either the process performance or an equivalent room-temperature pH response. In addition, the probes operating at high temperature are constantly operating at that high temperature throughout their life. There is no sticking the probe in hot stuff and pulling it out after the reading where the probe undergoes significant thermal stress. Its always hot!

You need to keep your pH probe at a relatively constant temperature. Since most brewers don't keep their probe at something like 150F at all times, it should be apparent that letting the wort sample cool to a reasonable room temperature is the way to produce acceptable probe lifespan.
 
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