Strange p.h issue

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MattGuk

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Hi guys,

I'm getting ready to brew this weekend for the 1st time in about 8 weeks.
Last time I brewed something a little odd happened in that after treating my waters Alkalinity with CRS I decided to just check my waters p.h after treatment and was at about 5.4.
Perfect, all pale malt grain bill, no roasted malt apart from about 100 grams of caramalt, no adjuncts so assumed the p.h would be in the region of about 5.2 - 5.3 ish 10 mins after mashing in.
Took a reading and it was saying 5.8, now it's worth mentioning that I calibrate my meter nearly every time I brew and did so the morning of this particular mash.
How did my p.h rise like that?
Or does it sound like a faulty meter?
It calibrates with the buffer solutions that I have no problem.
 
Hi guys,

I'm getting ready to brew this weekend for the 1st time in about 8 weeks.
Last time I brewed something a little odd happened in that after treating my waters Alkalinity with CRS I decided to just check my waters p.h after treatment and was at about 5.4.
Perfect, all pale malt grain bill, no roasted malt apart from about 100 grams of caramalt, no adjuncts so assumed the p.h would be in the region of about 5.2 - 5.3 ish 10 mins after mashing in.
Took a reading and it was saying 5.8, now it's worth mentioning that I calibrate my meter nearly every time I brew and did so the morning of this particular mash.
How did my p.h rise like that?
Or does it sound like a faulty meter?
It calibrates with the buffer solutions that I have no problem.
You cooled your sample to 20 C? And did you take another sample later?
 
Yep, cooled to 20°c, to be honest I didnt take a 2nd sample, but this was after 10 mins and also recirc the whole time.
Should I take 2 or 3 reading?
 
Yep, cooled to 20°c, to be honest I didnt take a 2nd sample, but this was after 10 mins and also recirc the whole time.
Should I take 2 or 3 reading?
I wouldn't rely on one reading, checking it a again at 20 or 30 minutes would give you more direction.
 
Water pH isn’t much of an indicator of mash pH. Mash pH comes about through the interaction of malt chemistry and water chemistry.

I recently had an unexpected 5.8pH after soaking my silicon recirc hoses in sodium percarbonate. Even after flushing the hoses through the carbonate salts left behind lined the inside of the hoses and was enough to raise the mash pH. I added more calcium in the mash to correct it and have since replaced my hoses. I won’t be soaking my hoses in sodium percarbonate again.
 
Thanks Foxy, good to know.
Is it possible to light malts to increase p.h?
I only mash the light base malt so my salt additions remain fairly constant. Even though the none fermentables are called none fermentables they do add some fermentable sugars so just adding the base malt and any adjuncts to the mash helps not only pH but forecast ABV. Just add the none fermentables at mash out or steep them.
Water pH isn’t much of an indicator of mash pH. Mash pH comes about through the interaction of malt chemistry and water chemistry.

I recently had an unexpected 5.8pH after soaking my silicon recirc hoses in sodium percarbonate. Even after flushing the hoses through the carbonate salts left behind lined the inside of the hoses and was enough to raise the mash pH. I added more calcium in the mash to correct it and have since replaced my hoses. I won’t be soaking my hoses in sodium percarbonate again.
Sodium perborate may be a better choice. I buy in bulk and I feel safer with a 25 kg bag of perborate in the shed than percarbonate.
 
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Thanks guys, I know water p.h isn't much of and indicator, but I have used CRS at the prescribed dose before and it's dropped the p.h waaaay to low, I guess through the water content of CRS evaporating?
That's why I just check it after treatment to make sure, just wonder why my mash p.h seemed to rise higher than my initial p.h.
 
Thanks Foxy, good to know.
Is it possible to light malts to increase p.h?
Yes, light malts increase pH, caramel and roasted malts decrease pH.

My water is also always at a pH of 5.5, after mashing with pilsner malt and wheat malt, I mostly have a pH of 5.8, and then I have to add extra acid to lower the pH still further. But I only do that after measuring the mash pH.

But if I mash with pale ale malt, with an EBC of around 9 (pilsner malt is 3), my pH is about perfect, 5.3 to 5.4.

And when using black roasted malt, I have to be very careful. Once I had to add sodiumbicarbonate to increase pH again.
 
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