Dark beer mash pH

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Beerrific

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I brewed a porter this weekend. First time I have ever used a pH meter to measure the mash pH. Thought I would share the results.

Original water (ppm):
Ca: 4
Mg: 1
Alkalinity as CaCO3: 22

In 5 gallons of mash water I adjusted to:
(Added 3g of CaCl2)
Ca: 47
Mg: 1
Alkalinity as CaCO3: 22

This gives an RA of -14.

Two commonly used water chemistry guides:
Palmer:
Using Morey this is a 31 SRM beer. Plamer calls for an RA of 256 to 315. To get the low end you would need 8g of baking soda in the mash.

Tasty Brew 2.0:
15.5 lbs total grain, 2.5lbs specialty non-roasted, 1.25lbs roasted. 31 SRM. Predicts a mash pH of 4.96 and I would need 8g of baking soda in the mash to get a pH of 5.2 which is my target.

Both those leave me with about 73ppm of sodium in the final beer. So not bad, below the threshold for a salty taste. I am lucky I have <10ppm Na in my tap water. If I did not have a pH meter, I could probably add this and not worry too much.

Actual brew day:
dough in, pH: 5.15
add 2g baking soda, pH 5.27
I let it sit for 5 minutes and checked it again: 5.24 and this is where it stayed for the length of the mash.

So a RA of 25 is sufficient for brewing a 31 SRM beer. I know others have said they have done similar things, but I guess it is nice to confirm this myself. I hesitate to draw any other conclusions from this being that it was just 1 sample. But, I am going to really try to take the mash pH for every beer from now on.
 
I checked mine for the first time this weekend. The ez water calculator estimated the ph @ 5.25, my new meter read 5.3, kinda cool.
 
interesting. so what would a RA of 287 do? i'm brewing a porter this weekend and my tap has a RA of 287
 
interesting. so what would a RA of 287 do? i'm brewing a porter this weekend and my tap has a RA of 287

If you plug your water numbers into the ez water spread sheet it will give you an approx ph, then you can do salt additions if necessary.
 
dough in, pH: 5.15
add 2g baking soda, pH 5.27
I let it sit for 5 minutes and checked it again: 5.24 and this is where it stayed for the length of the mash

So a RA of 25 is sufficient for brewing a 31 SRM beer.

And for a 4 SRM beer and a 84 SRM beer. There is really very little connection between color and RA. As you are now checking mash pH you can pretty much forget that you ever heard that the 2 are correlated (they are, of course, but it shouldn't affect the way you brew).

As you seem concerned about increased sodium in your beer let me suggest that instead of increasing mash pH with sodium bicarbonate you use calcium carbonate or calcium hydroxide (pickling lime) as the source of alkalinity. In either case you do the same thing - sprinkle the dose onto the mash, mix in thoroughly, wait a few minutes and then measure pH. Calcium carbonate is probably the most commonly used for this purpose because it is found in every LHBS. It works but slowly because it is insoluble and, according to Kai's experiments, not completely for that same reason. Lime, OTOH, is quite soluble and should, thus, work as fast as the sodium bicarbonate. It can be obtained in the canning department of most large supermarkets. In either case you are increasing desirable calcium rather than undesirable sodium in the course of adjusting mash pH.



I hesitate to draw any other conclusions from this being that it was just 1 sample. But, I am going to really try to take the mash pH for every beer from now on.

Just write your obervations in your brewing log and draw conclusions when you have accumulated a number of them. What you saw seems completely normal to me.
 
As you seem concerned about increased sodium in your beer let me suggest that instead of increasing mash pH with sodium bicarbonate you use calcium carbonate or calcium hydroxide (pickling lime)...

At what point should i start worry about the sodium? With 2g in the mash and none in the sparge that leaves something like 24ppm before the boil. From this experience I doubt I will ever need much more than 2g. I have some pickling lime in the closet, maybe I will try that next time.
 
And for a 4 SRM beer and a 84 SRM beer. There is really very little connection between color and RA. As you are now checking mash pH you can pretty much forget that you ever heard that the 2 are correlated (they are, of course, but it shouldn't affect the way you brew).

BTW Kai found that: "the specific acidity (titratable acidity per kg of malt) of crystal malts increases at a slope of about 0.13 mEq·kg-1·EBC-1 (r2= 0.77), [and] roasted malts have a specific acidity of about 40 mEq·kg-1 regardless of their color." (see: http://braukaiser.com/documents/effect_of_water_and_grist_on_mash_pH.pdf Sections 3.3 - 3.5 PLEASE READ).

The reason I mention this is to point out that the EZ 2.0 asks for SRM (and % of malt types) for the purpose of figuring out the breakdown of the grist - i.e. how much (and what color) is crystal, how much roasted, etc., so it can then, based on kai's experiments, estimate mash pH. It does not necessarily use SRM to make a direct correlation to RA as a whole.

Just write your obervations in your brewing log and draw conclusions when you have accumulated a number of them.

AJ, I presume that by now you have made a substantial number of entries in your brewing log. Any chance you would be able to share some of your data with me?
 
At what point should i start worry about the sodium? With 2g in the mash and none in the sparge that leaves something like 24ppm before the boil. From this experience I doubt I will ever need much more than 2g. I have some pickling lime in the closet, maybe I will try that next time.

Unless your doctor has told you to avoid sodium then you should start worrying about it when you find the beer tastes of it more than you want it to. I often suggest people dissolve a little sodium bicarbonate in a glass of water to get a feel for what it tastes like. When you use sodium bicarbonate to set mash pH most of the bicarbonate turns into CO2 and escapes but not all of it. At pH5 4% remains; at pH 5.2, 6%; at pH 5.4, 9.5% and so on. If you use chalk (calcium carbonate), the same thing happens but you wind up with less residual at a given pH because it takes half as many CO3-- ions as HCO3- ions to neutralize the same amount of acid (and you get the secondary benefit of beneficial calcium instead of useless sodium as the cation). If you use lime (Ca(OH)2), there is no residual bicarbonate (the product of the neutralization is water) and you get calcium as the anion.

Now some authors feel that some residual bicarbonate is important in some beers. For example, Daryl Richman in his monograph on Bock beer recommends it.

Once you get the mash pH under control by proper use of a pH meter, salts, acids and grains (the science part) , the rest of the job is tuning for taste - the artsy part.
 
Awesome thread. This PH problem with dark grains is amplified in PM brews.

Having gone back to PM's I put baking soda in any dark brew.

I believe this is the source of the extract TWANG myself, which I have eliminated.
 
partial mash? lol

my tap water has a sodium level of 211 ppm (softened water...) and it doesn't taste salty
 
No, I was actually referring to post marital brews.:drunk:

The alternatives to AG being extract and partial mash, take your best guess.
 
WOW. That is my strangest ever thread jack.

Yeah Partial Mash..........

So anyways, baking soda in dark PARTIAL MASH brews.:drunk:
 
So a RA of 25 is sufficient for brewing a 31 SRM beer. I know others have said they have done similar things, but I guess it is nice to confirm this myself. I hesitate to draw any other conclusions from this being that it was just 1 sample. But, I am going to really try to take the mash pH for every beer from now on.

An update to this. I brewed another dark beer this weekend. Darker: 41 SRM.

I mashed in with an RA of -14 and hit a mash pH of 5.3. I had the pickling lime ready to go, but did not need any. So with limited (n=2) results I am starting to conclude that it is not SRM that drives pH (obviously) but rather which specialty/roasted grains you have in there or the ratio of specialty/roasted to base malt.
 
An update to this. I brewed another dark beer this weekend. Darker: 41 SRM.

I mashed in with an RA of -14 and hit a mash pH of 5.3. I had the pickling lime ready to go, but did not need any. So with limited (n=2) results I am starting to conclude that it is not SRM that drives pH (obviously) but rather which specialty/roasted grains you have in there or the ratio of specialty/roasted to base malt.

To take this further, what about your sparge water? Have you used the meter and taken the pH during the sparge?

I guess what I'm thinking is that I haven't really acidified my sparge water, but I need to in order to really follow through with my water chemistry. Initially, I treated all my water. But I noticed that some of the salts were still in the bottom of the HLT. So I started focusing on the mash, and noticed that many techniques involved adding salts to the BK. I've been sort of ignoring that final frontier.

My question is twofold, I guess- if the sparge water needs acidified, would it be better to use lactic acid (liquid) or to work harder to dissolve the salts in the HLT, and of course, when the mash was 5.24, what was the sparge?
 
My question is twofold, I guess- if the sparge water needs acidified, would it be better to use lactic acid (liquid) or to work harder to dissolve the salts in the HLT, and of course, when the mash was 5.24, what was the sparge?

Lactic (or another) acid is really the only choice here. The salts we use are those of potassium (rarely), magnesium, calcium and sodium. The hydroxides of all these are strong bases so any salt from a strong acid (sulfuric or hydrochloric) e.g. calcium sulfate, calcium chloride, magnesium sulfate, magnesium chloride, potassium sulfate, potassium chloride will be neutral (no effect on pH) whereas salts of a weak acid (carbonic) such as sodium carbonate, sodium bicarbonate, and calcium carbonate will be basic and raise pH. The pH lowering calcium - phosphate reaction does not take place in the sparge as it takes place in the mash and there should not be much phosphate left to react. Perhaps in a mash with very little calcium some phosphate might make it through to the sparge but as malt is about 0.15% magnesium by weight I'd think magnesium phosphate (about a quarter as soluble as chalk) might clean out any phosphate not grabbed by calcium.

But you really shouldn't have to treat sparge water unless the untreated water is quite alkaline. Measure pH and gravity as you run off. If pH goes above about 6 while gravity is still bigger than, say, 5° P then yes, you should acidify. OW, don't worry about it.
 
Lactic (or another) acid is really the only choice here. The salts we use are those of potassium (rarely), magnesium, calcium and sodium. The hydroxides of all these are strong bases so any salt from a strong acid (sulfuric or hydrochloric) e.g. calcium sulfate, calcium chloride, magnesium sulfate, magnesium chloride, potassium sulfate, potassium chloride will be neutral (no effect on pH) whereas salts of a weak acid (carbonic) such as sodium carbonate, sodium bicarbonate, and calcium carbonate will be basic and raise pH. The pH lowering calcium - phosphate reaction does not take place in the sparge as it takes place in the mash and there should not be much phosphate left to react. Perhaps in a mash with very little calcium some phosphate might make it through to the sparge but as malt is about 0.15% magnesium by weight I'd think magnesium phosphate (about a quarter as soluble as chalk) might clean out any phosphate not grabbed by calcium.

But you really shouldn't have to treat sparge water unless the untreated water is quite alkaline. Measure pH and gravity as you run off. If pH goes above about 6 while gravity is still bigger than, say, 5° P then yes, you should acidify. OW, don't worry about it.

Thanks! My untreated water is quite alkaline. One of the fixes I've found for the mash has been dilution with RO water, usually in the neighborhood of 35% and adding some salts in small amounts- usually 3 grams CaCl2 and often a couple of grams of CaSO4. I've been focusing on the mash, but I think the next frontier, so to speak, will be checking the pH and gravity of the sparge.

To cover my bases, I've been batch sparging lately, using the same % of my tap water and RO water. Kind of taking the easy way out, at the moment!
 
I batch sparge and have taken the pH of the mash with the sparge water in there and it is always in the 'safe' range (has always been in the 5s). This is in agreement with most batch sparging "experts."

I treat my mash water with salts separately in the mash vs. sparge. I add the mash salts directly to the mash and the rest to the boil kettle. I would treat it all at once, but I have small second kettle so I have to heat it all separately.
 
I batch sparge and have taken the pH of the mash with the sparge water in there and it is always in the 'safe' range (has always been in the 5s). This is in agreement with most batch sparging "experts."

I treat my mash water with salts separately in the mash vs. sparge. I add the mash salts directly to the mash and the rest to the boil kettle. I would treat it all at once, but I have small second kettle so I have to heat it all separately.

Thanks for the info!

Maybe sometime soon I'll go back to fly sparging and checking my sparge pH and gravity, the way ajdelange suggests. I'm definitely learning more about water chemistry every day- but I have to do baby steps.

My understanding is that batch sparging does change the importance of water treatments- that's why I've started batch sparging again after all this time!
 
As you seem concerned about increased sodium in your beer let me suggest that instead of increasing mash pH with sodium bicarbonate you use calcium carbonate or calcium hydroxide (pickling lime)....

How much pickling lime should I expect to need to add? In general. Like 1 gram? More/less?

Also, all these pH measurements people quote, they are at room temp (20C), right? All the ones I mentioned above were at mash temps. So at room temp my mash numbers would have been higher, like 5.6. So I did not really need to add any baking soda at all.
 
How much pickling lime should I expect to need to add? In general. Like 1 gram? More/less?

Also, all these pH measurements people quote, they are at room temp (20C), right? All the ones I mentioned above were at mash temps. So at room temp my mash numbers would have been higher, like 5.6. So I did not really need to add any baking soda at all.

The second paragraph more or less answers the question posed in the first. One has to be careful when looking at given pH data as it is all too often that the temperature at which the measurement is taken is not given. This is even so in the professional literature. One could, at one time, assume that pH measurements were at lab temperature based on the need to move a sample to a laboratory to make the measurement but with modern, handheld meters this is no longer the case. Everyone knows, or should know, that high temperatures shorten electrode life appreciably and that's a pretty good basis for assuming that measurements are room temperature measurements but it's not certain that this is the case.

The answer to the lime question is "as much as is needed to get mash pH into the right range" and that amount should be 0 in most cases. If mash pH is indeed too low then add in very small increments - say 0.1 gram. Stir in thoroughly, wait and check pH repeating as necessary. Make a note of how much you use. You should then be able to hit it pretty close with a single addition the next time you brew this beer.
 
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