Mash pH estimation in water calculation

[Brewer #422640]

Hello,

I've been all-grain brewing for a year now, and I'm planning my 12th brew which will be my first attempt at a stout.
I want to get into water chemistry this time, and after lots of reading and pondering I started using the water calculator here on Brewer's Friend.
But there is something bugging me:

The mash pH estimation says it is for a sample cooled to room temp. And I understand, from Palmer's book, that the mash pH is 0.3-0.35 pH lower at mash temp compared to room temp.

With my water profile, (which is medium-hard, residual alkalinity is ~100 ppm as CaCO3), and my dark stout grist, the calculator is estimating a mash pH (at room temp) of 5.7. There's a little orange arrow saying this is a bit high. But if this is a room temp, then at mash temp it's more like 5.35-5.4. Isn't that pretty ideal? Why is the calculator telling me it's too high?

 

[Brew Cat]

Hello,

I've been all-grain brewing for a year now, and I'm planning my 12th brew which will be my first attempt at a stout.
I want to get into water chemistry this time, and after lots of reading and pondering I started using the water calculator here on Brewer's Friend.
But there is something bugging me:

The mash pH estimation says it is for a sample cooled to room temp. And I understand, from Palmer's book, that the mash pH is 0.3-0.35 pH lower at mash temp compared to room temp.

With my water profile, (which is medium-hard, residual alkalinity is ~100 ppm as CaCO3), and my dark stout grist, the calculator is estimating a mash pH (at room temp) of 5.7. There's a little orange arrow saying this is a bit high. But if this is a room temp, then at mash temp it's more like 5.35-5.4. Isn't that pretty ideal? Why is the calculator telling me it's too high?

I'm not certain but the estimated Ph is calculated on the site is calculated at the temperature you input in your mash field .
That's what I assumed. The calculator does the math so you don't have to

 

[Brewer #422640]

I'm not certain but the estimated Ph is calculated on the site is calculated at the temperature you input in your mash field .
That's what I assumed. The calculator does the math so you don't have to

Hmm, it doesn't seem to be linked to my mash temp field.
The * part suggests the prediction is for RT:

 

[Brew Cat]

I see that now
well its miniscule so no worries IMO
If you're adding acid maybe a tad more but its fine if you don't.

 

[Megary]

My understanding is that brewing pH is always measured and referenced at 20C / 68F. I don't believe the "correction" factor is anything hard and fast so I wouldn't put much stock in .30-.35. Yes, pH will measure lower at mash temperature but what the difference is will depend on grist, water composition and probably other factors as well.
For the OP, the calculator is telling you that your mash pH (as measured at room temp) will be a little high without the addition of a bit of acid.

 

[Megary]

the calculator is estimating a mash pH (at room temp) of 5.7. There's a little orange arrow saying this is a bit high. But if this is a room temp, then at mash temp it's more like 5.35-5.4. Isn't that pretty ideal?

To clarify, the short answer is no. Mash pH at mash temperature is, for the most part, irrelevant. The calculator is suggesting a range of pH's as measured at ≈ room temperature. What your pH measures at mash temperature (not sure how wise or accurate this would be to measure anyway) is not likely predictive to what it will measure at room temperature.

 

[Brewer #422640]

To clarify, the short answer is no. Mash pH at mash temperature is, for the most part, irrelevant. The calculator is suggesting a range of pH's as measured at ≈ room temperature. What your pH measures at mash temperature (not sure how wise or accurate this would be to measure anyway) is not likely predictive to what it will measure at room temperature.

Yes, I agree it would not be so reliable to measure pH at mash temp. It's good to know you believe pH should always be considered at room temp. I've ordered a pH meter and will in any case try to measure the mash pH after taking a sample out and cooling it.

So, according to the calculator, brewing a stout with my medium-hard water would ideally require a small acid addition?
That's not what I was expecting - I was all geared up to raise the pH a bit to brew a stout, it's what you read in all the books, I've seen stout recipes saying to add bicarb unless you have very hard water.
Also in Palmer's book: there's an example for a dark stout requiring residual alkalinity of ~200 ppm as CaCO3, and a mash pH over 6. For my water this would require a good bit of bicarb. But this is the opposite of what the calculator on here is telling me?

And as for my golden and pale ales, it seems I should have been adding a healthy slosh of acid all along!

 

[Zambi]

I hope you ordered calibration solutions with your pH meter.
They are finnicky instruments. Keep the "tips/sensors" covered in liquid

 

[Megary]

Yes, I agree it would not be so reliable to measure pH at mash temp. It's good to know you believe pH should always be considered at room temp. I've ordered a pH meter and will in any case try to measure the mash pH after taking a sample out and cooling it.

So, according to the calculator, brewing a stout with my medium-hard water would ideally require a small acid addition?
That's not what I was expecting - I was all geared up to raise the pH a bit to brew a stout, it's what you read in all the books, I've seen stout recipes saying to add bicarb unless you have very hard water.
Also in Palmer's book: there's an example for a dark stout requiring residual alkalinity of ~200 ppm as CaCO3, and a mash pH over 6. For my water this would require a good bit of bicarb. But this is the opposite of what the calculator on here is telling me?

And as for my golden and pale ales, it seems I should have been adding a healthy slosh of acid all along!

My water is similar to yours and for a Stout I also have to add a bit of acid and usually aim for about 5.6 pH. Never heard of targeting a mash pH over 6. But if it came from Palmer I wouldn’t dismiss it.

As a side note, I never target bicarbonate numbers. Once the pH is in the zone, I care not what the HCO3 says.

 

[HighVoltageMan!]

But if this is a room temp, then at mash temp it's more like 5.35-5.4.

Yes. 5.7 pH at room temperature is not out of line, expect a mash pH of 5.4-5.5. If your pH is at 5.7 at mash temperatures, then expect to read +5.9 at room temperature. pH changes with temperature and has negative temperature coefficient, meaning as temperature increases, the pH decreases.

I don't rely on mash pH calculators because, although they are often close, they are also in accurate at times (ph can change with lot numbers from the same malt). Over the years brewing and measuring pH, I found the optimal pH in the mash is 5.4 for conversion.

The other thing I learned was it's easy to lower pH and damn near impossible to raise it without adding sodium. The only reliable salt you can add easily to the mash or wort to raise pH is sodium bicarbonate (baking soda). Slaked lime works, but not as well as baking soda. Calcium carbonate is completely worthless unless it has been dissolved into solution in the presence of co2 (it needs carbonic acid to dissolve into solution).

If you are getting a pH meter, use the calculator to estimate the pH and measure it at room temperature. If your going to off on pH, it's best to be high. Acid additions reliably lower pH. You can use lactic or phosphoric acid. Make sure you know the concentration of the acid. Most lactic acids come as 88% concentrations. Phosphoric can come in anywhere from 10% to 85%. Both acids perform similarly when the concentrations are close. Lactic is the most commonly used by brewers, but personally, I prefer 85% phosphoric acid. It's what I learned on and it's very reliable.

Mash pH levels are important for starch conversion. Boil and pitch pH levels set up the overall best pH for the clarity, color and proper pH for yeast health.

This is my pH levels when brewing:

Mash pH of @ 5.6 at 80F provides the ideal environment for enzyme activity. It's a little low for alpha amylase and a little high for beta amylase, right in the middle of both. Acidifying sparge water (if you sparge) will keep the mash pH in check to avoid leeching tannins. The mash pH should never exceed 6.0 at room temperature.

I boil at 5.1 to 5.15 for light beers and 5.2-5.3 for darker beers. Pitch pH for light beers is between 5.05-5.15. Darks beers are 5.25-5.35. The pitch pH sets up the final beer pH which will be between 4.1-4.4 depending on yeast strains. The yeast will drop the pH to level the strain likes to be at. If the pitch pH is too high, the yeast struggles to lower the pH and it creates a less than optimal environment. The yeast cells excrete acids to raise the internal cell pH above the wort/beer pH. This makes it easier for the yeast cell to bring in sugars and nutrients through the cell wall.

Get a pH meter and use it. It's one of the easiest ways to positively impact beer quality.

I'll get off my soap box now.

 

[Brew Cat]

Yes. 5.7 pH at room temperature is not out of line, expect a mash pH of 5.4-5.5. If your pH is at 5.7 at mash temperatures, then expect to read +5.9 at room temperature. pH changes with temperature and has negative temperature coefficient, meaning as temperature increases, the pH decreases.

I don't rely on mash pH calculators because, although they are often close, they are also in accurate at times (ph can change with lot numbers from the same malt). Over the years brewing and measuring pH, I found the optimal pH in the mash is 5.4 for conversion.

The other thing I learned was it's easy to lower pH and damn near impossible to raise it without adding sodium. The only reliable salt you can add easily to the mash or wort to raise pH is sodium bicarbonate (baking soda). Slaked lime works, but not as well as baking soda. Calcium carbonate is completely worthless unless it has been dissolved into solution in the presence of co2 (it needs carbonic acid to dissolve into solution).

If you are getting a pH meter, use the calculator to estimate the pH and measure it at room temperature. If your going to off on pH, it's best to be high. Acid additions reliably lower pH. You can use lactic or phosphoric acid. Make sure you know the concentration of the acid. Most lactic acids come as 88% concentrations. Phosphoric can come in anywhere from 10% to 85%. Both acids perform similarly when the concentrations are close. Lactic is the most commonly used by brewers, but personally, I prefer 85% phosphoric acid. It's what I learned on and it's very reliable.

Mash pH levels are important for starch conversion. Boil and pitch pH levels set up the overall best pH for the clarity, color and proper pH for yeast health.

This is my pH levels when brewing:

Mash pH of @ 5.6 at 80F provides the ideal environment for enzyme activity. It's a little low for alpha amylase and a little high for beta amylase, right in the middle of both. Acidifying sparge water (if you sparge) will keep the mash pH in check to avoid leeching tannins. The mash pH should never exceed 6.0 at room temperature.

I boil at 5.1 to 5.15 for light beers and 5.2-5.3 for darker beers. Pitch pH for light beers is between 5.05-5.15. Darks beers are 5.25-5.35. The pitch pH sets up the final beer pH which will be between 4.1-4.4 depending on yeast strains. The yeast will drop the pH to level the strain likes to be at. If the pitch pH is too high, the yeast struggles to lower the pH and it creates a less than optimal environment. The yeast cells excrete acids to raise the internal cell pH above the wort/beer pH. This makes it easier for the yeast cell to bring in sugars and nutrients through the cell wall.

Get a pH meter and use it. It's one of the easiest ways to positively impact beer quality.

I'll get off my soap box now.

Everyone has their thing I guess

 

[Donoroto]

Yes, I agree it would not be so reliable to measure pH at mash temp. It's good to know you believe pH should always be considered at room temp. I've ordered a pH meter and will in any case try to measure the mash pH after taking a sample out and cooling it.

So, according to the calculator, brewing a stout with my medium-hard water would ideally require a small acid addition?
That's not what I was expecting - I was all geared up to raise the pH a bit to brew a stout, it's what you read in all the books, I've seen stout recipes saying to add bicarb unless you have very hard water.
Also in Palmer's book: there's an example for a dark stout requiring residual alkalinity of ~200 ppm as CaCO3, and a mash pH over 6. For my water this would require a good bit of bicarb. But this is the opposite of what the calculator on here is telling me?

And as for my golden and pale ales, it seems I should have been adding a healthy slosh of acid all along!

Another option is a few ounces of acidulated malt.

 

[Mont Y. Märzen]

I hope you ordered calibration solutions with your pH meter.
They are finnicky instruments. Keep the "tips/sensors" covered in liquid

And be sure to follow the instructions for the meter about rinsing in between samples!

 

[Mont Y. Märzen]

Yes, I agree it would not be so reliable to measure pH at mash temp. It's good to know you believe pH should always be considered at room temp. I've ordered a pH meter and will in any case try to measure the mash pH after taking a sample out and cooling it.

So, according to the calculator, brewing a stout with my medium-hard water would ideally require a small acid addition?
That's not what I was expecting - I was all geared up to raise the pH a bit to brew a stout, it's what you read in all the books, I've seen stout recipes saying to add bicarb unless you have very hard water.
Also in Palmer's book: there's an example for a dark stout requiring residual alkalinity of ~200 ppm as CaCO3, and a mash pH over 6. For my water this would require a good bit of bicarb. But this is the opposite of what the calculator on here is telling me?

And as for my golden and pale ales, it seems I should have been adding a healthy slosh of acid all along!

From what I learned here on the Forums, if you are measuring pH with a meter, forget and ignore everything about Residual Alkalinity(RA). RA is a 'rule of thumb' for those who can't/don't measure pH.

If you're mashing all of your grains together, then I'd doubt an acid addition would normally be required, but I've seen it happen when my tap water's pH was high. An alternative to acid would be to cut your source water with distilled/RO. That will also affect your salt calculations, but the Advanced Water Calc can handle such blended source solutions.

Keep in mind, any suggestion you see that isn't qualified is likely making assumptions. That is, 'all the books' telling you to raise pH for a Stout are unqualified, and are assuming your source water pH is 'standard' or 'average'. (which is likely also not defined) Now, it could be that they do offer qualified specifics, but maybe in a footnote, or it was worded in such a way that you didn't catch it.

My source water can vary from 7.8 to 8.6 throughout the year. I measure pH each batch of strike water in the kettle before dough-in and adjust my water calc as needed.

Since I now hold back my dark grains for Vorlauf, I'm always adding acid because for most of the mash, it is essentially a pale beer.

 

[Mont Y. Märzen]

As a side note, I never target bicarbonate numbers. Once the pH is in the zone, I care not what the HCO3 says.

I do this too, but I might be about to change that.

HCO3 is difficult, if not impossible to lower by adding anything to the strike. Mine is fairly high at 220ppm, but I like to brew Amber to Black beer so I never really concerned myself with it. My Pales turn out fine anyway.

My brewing buddies sometimes cut in distilled or switch to it entirely for their pale beers with good results, so I may start doing the same.

But for one particular recipe, I might try entirely distilled and then adding lots of Baking Soda with a pinch of Table Salt. When I first brewed this experimental-style batch, I nailed it. But that was before I got into water calcs and pH. I haven't been able to duplicate it since. That first run was a 'gypsy' brew at my Mom's house. Just recently, I had a water test done there and the Bicarbonate and Sodium were WAY off from my usual source water here at home. (220 v. 257 HCO3 & 29 v. 116 Na) So when I make another attempt, just for that one recipe, I think I'll try going all distilled and building up to match that water report and see if it makes a difference in the final product.

 

[Brew Cat]

I rarely use my Ph meter other than for kettle sours, After verifying the water calculator on BF was pretty much spot on it seemed redundant. A pt up or down doesn't make a difference in my experience

 

[Brewer #422640]

Thanks all for lots of useful insights.

I used to use pH meters in the lab at my previous job, so I'm confident with looking after them, calibrating etc.

This is my pH levels when brewing:

Mash pH of @ 5.6 at 80F provides the ideal environment for enzyme activity. It's a little low for alpha amylase and a little high for beta amylase, right in the middle of both. Acidifying sparge water (if you sparge) will keep the mash pH in check to avoid leeching tannins. The mash pH should never exceed 6.0 at room temperature.

I boil at 5.1 to 5.15 for light beers and 5.2-5.3 for darker beers. Pitch pH for light beers is between 5.05-5.15. Darks beers are 5.25-5.35. The pitch pH sets up the final beer pH which will be between 4.1-4.4 depending on yeast strains. The yeast will drop the pH to level the strain likes to be at. If the pitch pH is too high, the yeast struggles to lower the pH and it creates a less than optimal environment. The yeast cells excrete acids to raise the internal cell pH above the wort/beer pH. This makes it easier for the yeast cell to bring in sugars and nutrients through the cell wall.

So does this mean you add some acid to hit your mash pH of 5.6, and then once sparged/lautered/drained you add a bit more acid to hit your boil pH of 5.1?

From what I learned here on the Forums, if you are measuring pH with a meter, forget and ignore everything about Residual Alkalinity(RA). RA is a 'rule of thumb' for those who can't/don't measure pH.

If you're mashing all of your grains together, then I'd doubt an acid addition would normally be required, but I've seen it happen when my tap water's pH was high. An alternative to acid would be to cut your source water with distilled/RO. That will also affect your salt calculations, but the Advanced Water Calc can handle such blended source solutions.

Keep in mind, any suggestion you see that isn't qualified is likely making assumptions. That is, 'all the books' telling you to raise pH for a Stout are unqualified, and are assuming your source water pH is 'standard' or 'average'. (which is likely also not defined) Now, it could be that they do offer qualified specifics, but maybe in a footnote, or it was worded in such a way that you didn't catch it.

That's good to know, I think I've been getting too tied up with my RA and trying to coax it into recommended range as well as worrying about mash pH.

The whole "Dublin has hard water so they brew stout" argument was what I was referring to in 'all the books'. So I was prepared to make my water a bit harder, or leave it alone. When I learned I might to go the other way and add a bit of acid, that's when I got confused and started questioning my whole understanding. But I've learned more from 30mins reading forum posts than any book so that's something.

Anyway, I will try to measure my pH and see how I go. I have acid on hand should I fancy using it. The best way to learn is by messing it up.
To be honest I'm more worried about overcarbonating it - this seems to be my achilles heel at the moment and I keep messing it up!

 

[Craigerrr]

I don't use the software here, but I trust the software that I use to make the calculations for me. I use RO water and add calcium chloride, gypsum, Epsom, canning salt, and acid malt to get to desired water profile for pales, and additionally baking soda for stouts/porters. I tried a few different meters that I found to be ineffective, and have no inclination to spend $200+ on a higher end meter. Courses for horses... I have had great results trusting the predictions of the software I use, but I can't comment on how reliable the water calculator is on Brewers Friend.

 

[Dave Y]

The whole "Dublin has hard water so they brew stout" argument was what I was referring to in 'all the books'. So I was prepared to make my water a bit harder, or leave it alone. When I learned I might to go the other way and add a bit of acid, that's when I got confused and started questioning my whole understanding. But I've learned more from 30mins reading forum posts than any book so that's something.

My local brewery let me bounce a bunch of questions off of them when I added the RO water. They add zero chemicals other than acid. Nothing.
They get the pH set, and rock and roll.

Humans have been brewing beer for thousands of years. It’s unlikely we’re going to find a new way to screw it up.

 

[Brew Cat]

I don't use the software here, but I trust the software that I use to make the calculations for me. I use RO water and add calcium chloride, gypsum, Epsom, canning salt, and acid malt to get to desired water profile for pales, and additionally baking soda for stouts/porters. I tried a few different meters that I found to be ineffective, and have no inclination to spend $200+ on a higher end meter. Courses for horses... I have had great results trusting the predictions of the software I use, but I can't comment on how reliable the water calculator is on Brewers Friend.

Well I've used Brewers Friend and BeerSmith water calculators and got similar results also used a Ph meter to check. Those all worked