So what could explain my continued high mash pH?

[Galena]

I consistently miss my pH target, the beer tastes okay so what's to worry about? It's frustrating though and I am at a loss.
My water analysis was carried out professionally albeit 10 months ago, but I do a regular Salifert test which is pretty close every time. My Bicarbonate level is only around 22 anyway.
I use Brewfather to calculate my additions and have started to overdo the treatment to try and get the pH down. I also back that up with EZ Water Calculator which tends to give similar results. I calibrate my Apera pH 60 meter and take the 15 minute sample reading at room temperature.
As an example, yesterday I brewed a Blonde Ale and went for a very low pH of 5.12 (not what I wanted but an attempt to get it to be where I did want it), the 15 min pH was 5.63.
Last week I brewed a Bitter and also targeted 5.12, that time I got it down to 5.4 and another brew on the same day also a bitter I got 5.34, both of these are acceptable though still way off what the calculators were saying.
I understand there are lots of guesswork in the calculators but nevertheless to be 0.5 out seems extreme?

I was wondering if it could be my method of adding minerals that they are not fully dissolving, I add to sparge water direct in the HLT with no acid (which is irrelevant for mash pH) I add acid to the mash water and have tried adding minerals to the water and to the mash directly after doughing in and stirring really well, but not sure it makes a difference.
Could it be the malt, yesterdays brew was just Maris Otter and 10% Wheat and this would perhaps explain a wider discrepancy for this mash than the darker bitters

My tap water profile from Salifert is Ca: 15 Mg: 4 Na: 9 Cl: 11 SO4: 32 HCO3: 22
My tap water analysis was Ca: 21 Mg: 10 Na: 9 Cl: 13 SO4: 31 HCO3: 18

 

[Hazelwood Brewery]

You may need a little more calcium in the mash water? What’s you mash water profile?

 

[Galena]

You may need a little more calcium in the mash water? What’s you mash water profile?

The mash profile is the same as the sparge profile except 4.5mls lactic acid added to it to target 5.12
mash water profile after additions Ca: 140 Mg:8 Na: 9 Cl: 153 SO4: 155 HCO3: 22
additions were 3.4g Gypsum, 5.3g CaCl, 0.8g Epsom Salt

 

[Hazelwood Brewery]

That should be plenty.

Re-reading your post I see you are taking pH measurements at room temperature. To gauge the pH of your mash water you need to take the measurement at mash temperature or your pH reading will be high by about 0.2

I add my minerals to the mash water just before heating. You seem to be adding yours at dough-in which should be fine but you could try adding them to the water like I do if you feel that’s in any way part of the cause.

 

[Galena]

Re-reading your post I see you are taking pH measurements at room temperature. To gauge the pH of your mash water you need to take the measurement at mash temperature or your pH reading will be high by about 0.2

As I understand it, mash pH is referenced at room temperature, not mash temperature, so if a style guide suggests mash pH of 5.2-5.4 then that means at room temperature, I know the difference is 0.2 - 0.3 lower at mash temperature. Also afaik, the meter probe can be damaged at such high temperatures.

I add my minerals to the mash water just before heating. You seem to be adding yours at dough-in which should be fine but you could try adding them to the water like I do if you feel that’s in any way part of the cause.

I always added my minerals as yourself, just before heating, I have only just tried at dough in recently to see if it made a difference.

 

[Hazelwood Brewery]

As I understand it, mash pH is referenced at room temperature

I think that’s what most would agree with but then you’re left with another question. ..

If the quoted pH for a beer is 5.2, is it actually 5.0 but shows as 5.2 at room temperature or is it actually 5.2 but you need to see 5.4 at room temperature?

 

[The Baron]

I just use Acidified malt to get my PH to somewhere near what it should be or odd time I use Lactic acid

 

[Rochefort]

The lactic acid probably isn't the strength you think it is or the strength you put in to the calculator.

I'd play around with the % strength of lactic acid rather than target a lower pH.

It is also possible that the probe drifts between calibration and reading, or that it doesn't do a proper slope and offset calibration.

 

[Hazelwood Brewery]

You might find this helpful and a source of comfort!

You’ll find the video here, this slide is 11 minutes in.

 

[Galena]

You might find this helpful and a source of comfort!

I have watched that video and you will see I commented and questioned it as John Palmer goes on to say "All professional brewing organisations have standard procedures for measuring mash, wort and beer pH at room temperature...............

A short conversation with Northern Brewer who then concluded "Without having had talk to John Palmer about this, we agree that mash pH measurements should be taken at room temperature (72F) unless using a sophisticated meter that can be set to auto adjust for temperature. And yes, 5.2 to 5.4 (or 5.6) is ideal. "

 

[Galena]

The lactic acid probably isn't the strength you think it is or the strength you put in to the calculator.

I'd play around with the % strength of lactic acid rather than target a lower pH.

It is also possible that the probe drifts between calibration and reading, or that it doesn't do a proper slope and offset calibration.

My Lactic Acid is labelled as 80%, most calculators default to 88%, but I have mine set to 80.

 

[Hazelwood Brewery]

I have watched that video and you will see I commented and questioned it as John Palmer goes on to say "All professional brewing organisations have standard procedures for measuring mash, wort and beer pH at room temperature...............

A short conversation with Northern Brewer who then concluded "Without having had talk to John Palmer about this, we agree that mash pH measurements should be taken at room temperature (72F) unless using a sophisticated meter that can be set to auto adjust for temperature. And yes, 5.2 to 5.4 (or 5.6) is ideal. "

Yes, large breweries have labs for taking measurements that are located elsewhere from where the mash is carried out so by the time the sample is measured the temperature has dropped.

Temperature adjustment is another misunderstood factor. The compensation is for the electrical characteristics of the probe not for the chemical pH variance that changes with temperature. IE even a temperature adjusted probe will read different pH at mash temperature and room temperature for the same wort.

I measure my pH at mash temps. I use a cheap pH meter (about £10) and it’s optimal temp range is up to 60C. Well optimal means best rather than maximum, right? My last pH meter gave up the ghost after two years and I reckon if that’s reduced life, for £10 I’m happy.

Bottom line I guess, if the beer tastes good and your efficiency is good enough ...

 

[Galena]

Looking at JP's How to Brew again he says
Mash pH should be measured by dipping out a small sample of wort, somewhere between 5 and 10 mins into the sacharification rest, and pouring it onto a shallow saucer to cool to near room temperature.
He goes on to say " Therefore, the commonly agreed target range for mash pH is 5.2 - 5.6, as measured at room temperature. (20-25C)........... pale beers seem to taste better with lower mash pH of 5.2 - 5.4, while dark beers tend to taste better with a slightly higher mash pH of 5.4 - 5.6"

 

[Hazelwood Brewery]

There is quite a lot of disagreement on this topic so I think you just need to pin your flag to someone’s mast.

I use RO water and often start with water that’s around 5.4 (pure water is “thirsty” and drinks up CO2 which acidifies the water). During the mash the pH settles at 5.1-5.2 measured at mash temperature. You could always try RO water if you want to try and get lower by removing all that alkalinity buffering - for pale beers

 

[peebee]

My Lactic Acid is labelled as 80%, most calculators default to 88%, but I have mine set to 80.

I was going to post something with a footnote pointing out to folk going on about acid strengths and acid malts that you're talking about acidifying your sparge water, not your mash water.

But your reply suggests I might be misinterpreting what you are doing wrong!

You are not acidifying your mash water are you?

 

[peebee]

Don't whatever else you do try RO water!

The problem you've got is your water is entirely unlike the water most people reading this forum have to deal with. And you will as a result collect some fairly baffling suggestions. I know, I've been through all this and have water with half the bicarbonates of yours.

 

[Hazelwood Brewery]

Don't whatever else you do try RO water!

Why please?

Edit: To answer my own question I’m guessing you mean because it’s bloody good in the first place (though maybe lacking a little Calcium).

 

[peebee]

"Mash Made Easy" is another freebie water calculator with a very diligent author. I use it alongside another calculator (Bru'n Water) because they work differently. At the moment I rely on the results from Bru'n Water because it gets closest. But it wont be forever, the water will change and MME will be closer (it uses more sophisticated predicting formulas). They are only calculators and only for predicting what to add (pH-wise).

I've had the opposite problem (I've had mashes measure <5.0), but it's beginning to swing back. Water with very low total dissolved solids naturally will swing about. And the water company will do their best to keep it stable (acid water rots their pipes!), and the result is water that you use will need to be tweaked from week to week to keep the pH right. If it's anything like I experience you never find the cause, hence I juggle two calculators and use the one providing the least stress.

 

[Galena]

You are not acidifying your mash water are you?

Yes, I am acidifying my mash water.

 

[peebee]

Yes, I am acidifying my mash water.

That's okay. I sound incredulous because it's the last thing I'd want to do, but it is what you might do in your situation.

Does your tap water's pH fluctuate? Weird question as source pH has little to do with water treatment for brewing. But with so little in the water it might suggest something (mine swings between 7.5 and 10, it certainly is suggesting something). I also find I must calibrate the pH meter every time I use it (a simple single point calibration device is a nightmare, a multi-point calibration tool immediately tells you if things have gone awry - last time I picked up my meter it displayed my tap water as pH12!).