Water chemistry Primer questions/advice

[mrpiper]

ajdelange,

Thank you very much for the primer! Time will tell, but it seems that this will allow me to turn another random element of my process into a variable that I can control.

 

[martinworswick]

very informative thread,i've read through it over a few days.

one question though, and i'm sure this has been asked but i can't recall seeing the answer

if i have a high bicarb figure and i have no r/o or distilled water to use then what would a baseline be to work from?

my figures are

ca 29.3,mg 4.1,na 2.5,s04 7.6,cl 1.1,hco3 100

 

[ajdelange]

Bicarbonate of 100 implies and alkalinity of about 82. Lots of people have brewed lots of beers with water this alkaline. I'd say just go ahead and brew with it being sure to use the sauermalz as recommended. I would hope that you would get a pH meter and monitor mash pH but for the time being just brewing with the water you have should work.

 

[martinworswick]

Bicarbonate of 100 implies and alkalinity of about 82. Lots of people have brewed lots of beers with water this alkaline. I'd say just go ahead and brew with it being sure to use the sauermalz as recommended. I would hope that you would get a pH meter and monitor mash pH but for the time being just brewing with the water you have should work.

thanks.
i have recently acquired a ph meter and used it for the first time today,ph 5.24,
i'm brewing jamils smoked porter recipe, i skipped the sauermalz for the simple reason i have none and added calcium chloride according to the recommendations

 

[ajdelange]

If you are getting pH 5.24 (room temperature, meter calibrated before taking measurments) then you don't need sauermalz. In fact you might want to consider adding a small amount of alkali (calcium carbonate or pickling lime) to the mash to pull the pH up to 5.3 - 5.4 (room temperature).

 

[orangehero]

When brewing a stout with soft water, would it be good practice to avoid adding calcium salts to the mash, instead waiting to add to kettle in order to avoid unnecessarily lowering the mash pH?

From what I understand, some of the calcium added to mash/sparge liquor is left behind in the mash, so kettle additions should therefore be reduced.

 

[jmf143]

You'll want at least 50 ppm calcium in the mash. the rest can go into the kettle.

 

[emjay]

(I apologize in advance that my own reply is mostly copy+pasted from the other thread... but, having just recalled this one even existed, it seemed apropos.)

Where do you get your phosphoric acid? Star San?

Most homebrew supply shops should have both lactic acid and phosphoric acid. I use lactic acid for German beer styles which traditionally would use saurmalz, and phosphoric acid for everything else since it is flavorless.

Yeah, that's why I asked. I've never actually seen it at any homebrew store though...

I would definitely ask them to carry it. 90% of the pro breweries I have been to use phosphoric acid.

As luck would have it, my lhbs JUST started carrying it. I picked up a gallon jug of the stuff - 70%. I take it this should last quite a while?

Interestingly, it's a Five Star product. It even has instructions for yeast washing right on the side of the jug.

He mentioned that he was getting a smaller size in soon as well. But the whole jug cost me $20 (and pretty much everything at my LHBS is overpriced), so I just went for it.

Still, it's a heck of a lot cheaper than a sack of acidulated malt, let alone a lifetime supply.

But, a big question for AJ: How much 70% phosphoric acid should I add to reproduce the pH adjustment per gram (or whatever unit you're comfortable with) of sauermalz?

 

[ajdelange]

The answer depends on a lot of things. Most obvious is how much acid is contained in a given weight of sauermalz and that varies. The thing I like about sauermalz is that the rule of thumb seems to work.

That aside the relative amounts of acid required depend on the pH shift. Assuming that you want to go from pH 5.6 to 5.4 it takes only slightly less 85% phosphoric acid, than 88% lactic acid. For example, if it takes 8.48 mL of lactic acid to lower the pH of a mash from 5.6 to 5.2 you can get the same result with 8.32 mL (2% less) of phosphoric. By weight, the same mash would require 0.824 grams of phosphoric acid but only 0.799 grams of lactic acid (because while phosphoric acid is a stronger acid it has a higher molecular weight). From this you should be able to figure our relative amounts of phosphoric and lactic of any strength and compare to sauermalz of any assumed % lactic.

 

[jmf143]

Is this a linear relationship we can simplify? If 8.32 ml of 85% phosphoric acid is eqivalent to 8.48 ml of 88% lactic acid and both reduce pH from 5.6 to 5.2, can we assume using 1/4 as much of either would reduce pH by .1? And does this hold true along the entire range of pH values likely to be encountered in a mash?

 

[ajdelange]

Forgot to mention that (phone rang). The math is definitely not linear but I think that over the limited range of pH adjustment we are talking about in correcting mash it is fine to model it as linear. Also, though the volume calculations I did were for 88% lactic and 85% phosphoric and acids of other strengths will have different densities I think it is safe to assume linearity there too as long as you aren't going too far away from the 70 - 90% range.

 

[emjay]

The answer depends on a lot of things. Most obvious is how much acid is contained in a given weight of sauermalz and that varies. The thing I like about sauermalz is that the rule of thumb seems to work.

Yeah, I know it depends on the amount of acid in the sauermalz, but wouldn't the rule of thumb HAVE to be assuming a certain acid content?

The answer depends on a lot of things. Most obvious is how much acid is contained in a given weight of sauermalz and that varies. The thing I like about sauermalz is that the rule of thumb seems to work.

That aside the relative amounts of acid required depend on the pH shift. Assuming that you want to go from pH 5.6 to 5.4 it takes only slightly less 85% phosphoric acid, than 88% lactic acid. For example, if it takes 8.48 mL of phosphoric acid to lower the pH of a mash from 5.6 to 5.2 you can get the same result with 8.32 mL (2% less) of lactic. By weight, the same mash would require 0.824 grams of phosphoric acid but only 0.799 grams of lactic acid (because while phosphoric acid is a stronger acid it has a higher molecular weight). From this you should be able to figure our relative amounts of phosphoric and lactic of any strength and compare to sauermalz of any assumed % lactic.

Acid content of sauermalz is measured in % w/w? So if I want to measure out the 70% phosphoric acid in volume, I have to convert that lactic acid content to volume first, and then convert to 85% phosphoric acid as you've done, and then adjust that volume for the 70% acid I have?

If that sounds about right... do you know what the density of 88% lactic acid is?

EDIT: Just noticed you MIGHT have kind of given it already as 0.799g/8.32mL. Is that accurate? Your use of the words, "For example, if it takes..." makes me think there's a slight possibility it may not be.

it takes only slightly less 85% phosphoric acid, than 88% lactic acid.

For example, if it takes 8.48 mL ... you can get the same result with 8.32 mL (2% less) of lactic.

Lastly, just for clarification - don't these two quotes sort of contradict each other?

 

[ajdelange]

Yeah, I know it depends on the amount of acid in the sauermalz, but wouldn't the rule of thumb HAVE to be assuming a certain acid content?

Probably but I don't know. It's Weyermann's rule of thumb.

Acid content of sauermalz is measured in % w/w? So if I want to measure out the 70% phosphoric acid in volume, I have to convert that lactic acid content to volume first, and then convert to 85% phosphoric acid as you've done, and then adjust that volume for the 70% acid I have?

Yes but of course to do that you would have to make and assumption about the lactic acid content of the malt. I think 2% (w/w) is probably a good assumption.

If that sounds about right... do you know what the density of 88% lactic acid is?

Yes, it's 1.206 gram/cc. 85% phosphoric is 1.690 gram/cc.

Lastly, just for clarification - don't these two quotes sort of contradict each other?

Yes, they do. My error. Acid names were reversed. I fixed it in the earlier post.

 

[RoadKing]

I'm getting ready to brew for the season and want to start fine tuning my water.
My water report from Ward is..calcium7 magnesium <0 sodium8 sulfate12
chloride10 bicarbonate 12.
I'm trying to use primer and spread sheets to have a starting point for adjustments. I haven't brewed, but am checking the numbers based on an all pale grist (20 lbs @ 1.3 water ratio)
My question is if I add sauermalz my alkalinity and ra goes into the negative
Is that OK or do I need some Alkalinity?
Also using that pale grist, EZ water estimates a PH of 5.7 and Bru'n water says 5.4, I have a PH meter and will check actual ph but after mashing in,but one is telling me to adjust up and the other down which makes it kind of confusing as to what additions I may need to make.
I've been reading alot and I am just trying to understand this stuff (my head hurts)
Thanks.

 

[ajdelange]

It is unusual to "need" akalinity and when you do it usually occurs when the beer has a lot of dark (crystal and or roast) malt in the grain bill. Sauermalz (acid) and alkalinity (base) offset one another so if you need alkalinity in a brew with sauermalz it means you have used too much sauermalz.

Your pH meter is really your best friend here. It will tell you whether you need more or less sauermalz (and in the cases where you need alkalinity it will guide you there too). Just remember that when sauermalz is used the initial pH reading is very probably going to be low - perhaps startlingly low. Be sure to recheck mash pH after about 15 - 20 minutes.

With a pale beer you are likely going to be fine with 2% - 3% sauermalz. You might want to grind 3%, add 2 and hold the last one in reserve to be added if the pH is too high with only 2%.

Remember to check mash pH on a sample cooled to room temperature.

 

[-TH-]

...Just remember that when sauermalz is used the initial pH reading is very probably going to be low - perhaps startlingly low. Be sure to recheck mash pH after about 15 - 20 minutes.

AJ, is that the time you generally recommend taking a measurement to get it's "true" mash pH, 15 - 20 minutes? Would you recommend not making any adjustments prior to that time?

 

[MichaelBrock]

AJ, is that the time you generally recommend taking a measurement to get it's "true" mash pH, 15 - 20 minutes? Would you recommend not making any adjustments prior to that time?

I was wondering the same thing. I have read in a different thread that most of the mashing "action" occurs in the first 20 minutes. How late is "too late" to adjust the ph?

 

[ajdelange]

It's a good question. If you measure the mash pH and it doesn't stabilize until 15 - 20 minutes then if it is correct, most of the conversion (for whichever enzyme is active at that temperature range) will have completed. If, however, it is not correct then you might assume that the conversion will not have been complete because of incorrect pH and that correcting it will allow the enzyme to finish its job. While that conceptually may be true it's probably also true that the resulting beer will not be as good as it would be if the mash pH were correct at the time of check. This pH monitoring is not really about a couple of points of efficiency. It is about beer flavor. Beer brewed with attention to mash pH just tastes better.

Thus if you are off and have to correct your beer will doubtless be good but not as good as it will be the next time you brew it because the fact that you corrected teaches you to use more or less acid (or alkali) the next time you brew this beer.

 

[jkarp]

I was wondering the same thing. I have read in a different thread that most of the mashing "action" occurs in the first 20 minutes. How late is "too late" to adjust the ph?

I think pH adjustments are really batch iterative. Learn from the current batch and apply to the next. If you taste the wort immediately after doughing in, it's already sweet. These reactions are darn near instantaneous.

 

[ajdelange]

A way around the lag question is to make a test mash - i.e. scale everything down to about a pound of grist and check the pH. If it doesn't come in right adjust the acid and try again. You will then know what to do for the main mash.

 

[-TH-]

AJ, how many minutes have you seen it take for a mash pH to stabilize?

 

[ajdelange]

Hard question to answer as pH changes continuously throughout the mashing process. The only time one really has to wait, in my experience, is when sauermalz is used. The pH can be alarmingly low at a first measurement but then drifts upward at a pretty good rate. After 10 minutes it will have increased dramatically. After 15 it should be close enough to it's "final" value that you could consider that an appropriate time to determine whether you have hit your target or not. Beyond 20 min it shouldn't change much.

If CaCO3 is used I'd expect equally long, or longer stabilization times but then I never use CaCO3 so I haven't much experience with that.

 

[emjay]

I'm surprised to hear that about sauermalz. I would have expected pH to be a bit high at first, and then drift downwards.

And why does CaCO3 take a long time? Is it just the poor solubility?

I just moved, so I have yet to brew a batch where I intentionally adjust pH. I have a gallon of Five Star 75% phosphoric acid, and also a small container of calcium hydroxide (for raising pH) that I bought in a Tamil grocery store, of all places. While looking for a specific ingredient for a beer I was planning, no less. No idea what they use it for (the owner took another little container and just showed me that he gets a bit on his finger and puts it on his tongue!), but it's clearly food-grade.

One thing I'm wondering though is that, even though the CaOH is a powder, the ingredients list says it contains both calcium hydroxide AND water. Is there a typical hydrate or something, or am I going to have to perform a titration to figure out what I'm working with?

 

[ajdelange]

I'm guessing that the lactic acid is quickly "washed" off the surface of the malt thus acidifying the liquor but takes time to penetrate into the grist where it reacts with the buffers in the malt.

Yes, calcium carbonate reacts slowly unless the pH is very low. IOW, if you put it in a beaker and pour strong mineral acid over it it will fizz giving off carbon dioxide. If you put it in water and bubble CO2 through the water it will take seemingly forever to dissolve.

Ca(OH)2 is used in western food preparation to offset acidity especially in the making if pickles.

Don't think slaked lime (calcium hydroxide) has water of hydration but if it is exposed to humid air it will, as will most substances, adsorb some water. It's probably not enough that it needs to be accounted for except in the most precise work.

 

[pickles]

A way around the lag question is to make a test mash - i.e. scale everything down to about a pound of grist and check the pH. If it doesn't come in right adjust the acid and try again. You will then know what to do for the main mash.

When doing this test is it appropriate to scale the mash water quantity down as well or is it irrelevant? Also, should it be mashed at the actual mash temp for the desired recipe?

 

[ajdelange]

Yes (it's relevant though mash pH is not strongly dependent on amount of water) and yes, test mash should be doughed in at the strike temperature you plan to use though the sample of liquid on which the pH is measured should be cooled to room temperature.

 

[jmf143]

Yes (it's relevant though mash pH is not strongly dependent on amount of water) and yes, test mash should be doughed in at the strike temperature you plan to use though the sample of liquid on which the pH is measured should be cooled to room temperature.

What if you re using an ice bath to cool the sample and wait too long i.e. it cools to 40 - 50 degrees? Will the pH measurement still be accurate?

 

[ajdelange]

No, the pH will continue increase as the temperature decreases.

 

[J_MAR]

Did you put it in the EZ 2.0? I've had pretty good luck with it so far.

I know for beers with SRM > about 40 things get skewed and I am working on that.

,

So 0.4g of Chalk or 0.28g of pickling lime is potentially enough to move the mash pH from 5.2 to 5.4? That seems like very little. Is it that much per gallon?

 

[TastyAdventure]

Hey guys, I'm about to brew an Octoberfest Ale and have been reading that soft water is important for this style. All I have ever really done before in the past is adjust for mash pH and add some calcium chloride (per this website: http://www.brewersfriend.com/mash-chemistry-and-brewing-water-calculator/ ) to as close to what they call a "Balanced profile"

Anyways, here's my water stats. How can I make my water softer?
Alkalinity: 73
Calcium: 48
Mag: 7
Sodium: 33
Sulfate: 74
Bicarbonate: 73
Chloride: 38
Hardness: 144

Thanks!