Techniques for taking pH samples from cooler mashtun

Does anyone have a particular technique for taking a sample from a cooler mashtun for pH measurement? I'm a bit confused on after mixing grain/water, should a draw a sample from the bottom through the ball valve or should I take a sample from the top immediately after mixing? If I do determine that I need to adjust pH do I add my chemicals, mix, rest for a few minutes then take an additional sample for measurement? I'm concerned that the constant mixing and opening may drop my temp down a bit too much. Any ideas and techniques are greatly appreciated. Thanks in advance for the help.

Don't take it immediately after mixing as it needs some time to work. I usually wait 15-20 minutes. I would not take it from the ball valve as there is no guarantee that the liquid in the valve ever probably mixed with the mineral additions. Would say add grain to mash water, then add minerals, mix up, then after 15 minutes, open up, give a stir, then take a reading from the top!

I want to piggy back off of this with a couple of questions I had as well

1. Should the sample be a mix of liquid and grains or all liquid?

2. Since it takes 15-20 minutes for the pH to stabilize, can you correct pH during the mash or is taking the reading really more to adjust your salt additions for the next time you re-brew the same recipe? In a 60 minute mash you can really only adjust twice and how effective is the adjustment midway through the mash anyway?

jdauria said:

Don't take it immediately after mixing as it needs some time to work. I usually wait 15-20 minutes. I would not take it from the ball valve as there is no guarantee that the liquid in the valve ever probably mixed with the mineral additions. Would say add grain to mash water, then add minerals, mix up, then after 15 minutes, open up, give a stir, then take a reading from the top!

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Thanks for the input.

I stir with thermometer, and scoop with a shot glass. Then let sit while it cools; then measure PH.

cpatel479 said:

I want to piggy back off of this with a couple of questions I had as well

1. Should the sample be a mix of liquid and grains or all liquid?

2. Since it takes 15-20 minutes for the pH to stabilize, can you correct pH during the mash or is taking the reading really more to adjust your salt additions for the next time you re-brew the same recipe? In a 60 minute mash you can really only adjust twice and how effective is the adjustment midway through the mash anyway?

Click to expand...

You should try to get mostly if not all liquid, although a little bit of grain particles shouldn't hurt anything. I have one of those stainless steel mesh tea strainers that I dip into the wort and suck up a sample with a syringe or pipette from the center.

Although you can try adjusting if you are way off target, it will only really help you the next time you brew the recipe. If you are worried about the software calculators being off you can always make a small test mash that will fit in a thermos.

I try to take a sample 5 mins after dough-in, at 30 minutes, and at the end of the mash, but 15-20 minutes will give you a reliable reading you can use to make future adjustments.

Calibrate my pH meter using correction table and preheating the buffer solution to 149F. I then take readings directly from the mash at various spots. I then adjust with PA rather than mineral additions. Usually only takes 5-10 mins using this process.