pH Consistently Below Calculations

[brodymnasse]

Hey friends. With my last four batches (10 gal.), I’ve been having trouble with hitting my pH targets (I’ve been low with each batch). Looking for some help if anyone is interested and has time. A few points:
- I use the EZ Water Calculator Excel spreadsheet
- I use 100% RO H20
- My additions are a combination of Calcium Chloride and Calcium Sulfate. I dose all water in the HWT, so all water is the same profile (I know some recommend adding these to the mash, but it seems like these additions have less impact than lactic acid on pH. Interested in hearing how others make their additions, but will try to focus on the lactic addition here)
- I’ve been using Meussdoerffer Acidulated Malt (changed somewhat recently from the LHBS)
- My pH meter has been calibrated for accuracy within the past month, and stored in storage solution since
I’m going to give the expected and actual (room temperature = 70F) post-mash and post-boil pH measurements. For the sake of simplicity, let’s assume that I’m using the spreadsheet correctly to calculate the expected pH correctly, and that I’m making the correct additions according to the calculations. I’ll break the batches into two categories
Lighter Beers where Acid Malt was Used
1. Saison: Target = 5.51, Post-Mash = 5.41, Post-Boil = 5.37 (the closest of the bunch)
2. ESB: Target = 5.48, Post-Mash = 5.19, Post=Boil = 5.16
Darker Beers where No Acid Malt Needed
1. Dark Mild: Target = 5.54, Post-Mash = 5.13, Post-Boil = 5.07, Finished Beer = 3.87 (boo)
2. Irish Stout: Target = 5.48, Post-Mash = 5.23, Post-Boil = 5.12
Some additional factors that may be useful to know:
- I use a Water/Grist ratio of 1.25 quarts per pound
- Typical mash time = 60 minutes
- I take my readings at the end of the mash (I know I should take them earlier and adjust, but I’ve been lazy…). I will recirculate ~2 gallons in the mash before taking a reading
I know there are a lot of factors that go into pH, but my recipes seem to run the spectrum. Here are some things that I’m going to try to isolate/test:
- I’ve purchased new pH 4.0 and 7.0 solution. Mine is about three years old. Does this stuff go bad?
- I will recalibrate my pH meter
- Check to see if Mussedoerffer Acid Malt has a higher acid content than others? Not sure how to find this out
- For the ESB, Mild, and Stout, I’ve been using a different base malt than usual (Crisp Gleneagles Maris Otter). Trying to figure out if this has a drastically different impact on pH than other Maris Otter (T. Fawcett, Muntons). Any thoughts?
- I’m going to do a few small test batches with all base malt, a wort ~15 SRM, and a dark test at 40+ SRM
Some other questions. If you look at the info and see something obvious that I’m doing wrong, that may be the best place to start
- Does anyone else use the EZ Water Calculator with good results?
- Which programs work best to calculate pH?
- Acid malt, lactic acid, or phosphoric acid? Any strong opinions for one over the others?
- When/How do you take initial mash pH readings? I’ve read that the pH will settle within 10-15 minutes. What’s the quickest way to cool the sample to get a room temperature reading (freezer?)
Long email, so kudos to anyone still reading. Apologies for the lengthy post, but this has been kicking my ass the past few brew days. Thanks all.

 

[bajaedition]

OK first you need a base line

do a beer and get use that as a base line

then do the same beer changing one item , and only one item

that way you know what you changed and how it effected the beer

then do the beer again, and change something else

when you get the thing correct, you will know what you were doing wrong

trying to fix something by changing the entire recipe is like throwing dust in the wind and trying to pick it all up again, never going to know where it all went

you need a base line of a single beer recipe and uses everything in the exact same amounts but one item so you know if that is the item you have to change

 

[Silver_Is_Money]

Do your beers taste good. Are your efficiencies typical for your setup? If so, then where is the concern?

 

[Oginme]

Based upon your results, target a bit higher for pH in the EZ Water Calculator by the mean difference you are seeing based upon your use of acid malt or not.

Realize that not every calculator can take into account the pH contribution of every malt existing. EZ Water uses a general pH contribution for 'toasted/roasted' malts, which covers a pretty large range of malts. I know from experience that there are vast differences in the mash pH for even 'standard' 2-row malts (Rahr ends up much lower than Breiss, for instance).

Given your excellent documentation so far, it should not be too hard to estimate where to set your aim to get the pH into the range you desire for the mash, which is all these calculators are intended to do.

 

[VladOfTrub]

The pH adjustments are made according to the optimum pH of the enzyme being activated at the optimum temperature of the enzyme. Before adding anything into the brewing water allow the inherent pH of the malt to adjust the mash liquid pH. Depending on the base malt and with using 100% RO @ 7.2 pH the inherent pH of malt can reduce mash pH to 5.8. Any pH adjustments performed should take place before enzymatic action occurs.
For many years I used Weyerman Sauer Malz. When Meussdoerffer became available a few years ago I tried it and stuck with it. In my opinion Meussdoerffer has a smoother, not as sharp tartness to it as Weyermans does. Do not assume that 10 percent addition of sauer malz shifts pH a point or whatever number is indicated in books about making home made beer. The pH of sauer malz varies.
Marris Otter is highly modified malt. The saving grace is that it is low in protein which means that it is loaded with sugar. However, due to the malt being highly modified the enzymatic richness is poor. I'd look more into the quality of the malt before worrying about the pH of the malt. In my opinion the malt being low in enzyme richness and very high in sugar content makes it very good malt for producing grain alcohol and maybe not so good for producing Ale, although the marketers selling the grain says it is fit for the liquid in the Holy Grail. Grain distillers use the same method as home brewers, single infusion. The single temperature method works because there is only one enzyme left in the malt to cause saccarification, Alpha. The sugar which Alpha releases is glucose a simple sugar which yeast loves and non fermenting sweet tasting sugar. The wort drawn from single infusion is sugar imbalanced. There's more to worry about than pH, starting with the brewing method and the malt.

 

[Yooper]

My advise is to try a different calculator. EZ water was always off for me, by about .3 (high), but Bru'nwater and often Brewer's Friend have been pretty accurate.

That's to predict a mash pH. The mash pH changes during the mash, so the mash pH is generally checked about 15 minutes in. The post-mash and post- boil pH will be lower.

Also, recalibrate your pH meter each brewday. Once a month just isn't going to cut it- it needs to be done before each testing day.

 

[Horseflesh]

I use Bru'n Water and find that my mash pH is consistently about 0.1 -
0.15 higher than the estimate. This isn't terrible, but I'd still like to improve it.

Is the best way to manage this to just fudge it, or is there a method to "calibrate" the spreadsheet?

 

[Silver_Is_Money]

Perhaps you could find an earlier version of Bru'n Water. The very latest versions seem to predict lower mash pH's than did earlier versions. Either that, or tweak your grains Lovibond colors a tad to compensate for the differential you are seeing.

For EZ Water you can tweak each grains DI Mash pH directly to bring the spreadsheets mash pH predictions into line with your measured actual mash pH readings. And while you are at it, you can also remove grains you don't use, and replace them with grains that you do use. Very quick and easy to do in this spreadsheet. And (until you decide to change them) the adjustments are permanent.

Or you can do what I've done, which is to abandon all of the current mash pH software, and create your own.

 

[Ceaver]

IME, one thing you'll want to double-check is the pH of your RO water. I have two different RO/DI systems and both produce water that is below 4 pH. Now, many people will tell you that pH of RO water doesn't matter and that all of your salt and possibly acid additions will get it where it should be.

However, that is not my experience. I've gotten the Ward labs analysis of my tap water, so I conducted a little experiment in which I made up two batches of a specific water profile for a recipe, using Bru'n Water, one using my tap and the other the RO. Lo and behold, the beginning pH of those two waters was quite different, after all additions were made, and I simply don't believe anyone who says that doesn't make a difference.

Wondering which batch had the significantly lower pH? It was the RO.

I'm still working on "fixing" my RO water, because I would prefer it, but not there yet...

 

[Yooper]

IME, one thing you'll want to double-check is the pH of your RO water. I have two different RO/DI systems and both produce water that is below 4 pH. Now, many people will tell you that pH of RO water doesn't matter and that all of your salt and possibly acid additions will get it where it should be.

However, that is not my experience. I've gotten the Ward labs analysis of my tap water, so I conducted a little experiment in which I made up two batches of a specific water profile for a recipe, using Bru'n Water, one using my tap and the other the RO. Lo and behold, the beginning pH of those two waters was quite different, after all additions were made, and I simply don't believe anyone who says that doesn't make a difference.

Wondering which batch had the significantly lower pH? It was the RO.

I'm still working on "fixing" my RO water, because I would prefer it, but not there yet...

It's not the pH of the water- it's the buffering capacity. The tap water obviously had some alkalinity in it, likely in the form of bicarbonate. That will mean a higher mash pH than using RO water with no to very little bicarbonate.

Water pH has very little to do with the mash pH.

 

[Silver_Is_Money]

Water pH has very little to do with the mash pH.

To expound upon this truth, mash pH is related to the waters alkalinity, and alkalinity is the measure of the waters carbonate content (typically reported as the waters CaCO3 and/or MgCO3 content), which is not something that is related to the waters pH.

 

[Ceaver]

Sure, that is generally what I've read and heard. I still think there's more to the puzzle here, though. For example, most people are lucky enough to have 7.0/7.2 pH RO water, as a previous poster mentioned. My research thus far has suggested that the reason my RO water doesn't is due to dissolved CO2 in the water, which RO cannot remove. So if the RO water has less buffering capacity AND a lot of dissolved CO2, which ultimately results in more H+ ions, perhaps this leads to a lower-than-desired mash pH. I haven't messed around with degassing yet and would prefer not to have to. Maybe the OP here is having a similar issue?

 

[Silver_Is_Money]

My homes RO water has alkalinity in the neighborhood of 26 ppm as CaCO3. That is because my well water that is its source has a whopping 436 ppm of alkalinity as CaCO3, and the RO unit can't get it below 26.

My RO water is also repeatedly measured to have a slightly acidic pH of 6.08.

 

[erock2112]

My recommendations:
- Calibrate the pH meter immediately before use. Otherwise you can't trust that it hasn't drifted.
- Use lactic or phosphoric acid instead of acidulated malt, since you can't be sure of the acid content of the acidulated malt.
- Make sure you're not reusing your buffer solutions, or they're going to be inaccurate.
- Use Brun Water to calculate mash pH. Many have found that it's the only calculator that gets anywhere close.

 

[Ceaver]

My well water is also repeatedly measured to have a slightly acidic pH of 6.08.

For curiosity's sake, what does your RO pH measure coming out of your unit?

FWIW, I have trouble hitting mash pH with my RO water, not my tap water. Something is amiss, and it may go beyond the basics of water chemistry. I'm no chemist, but I can say through experience that something is up.

Thanks for the input. Cheers!

 

[Silver_Is_Money]

For curiosity's sake, what does your RO pH measure coming out of your unit?

Oops, I somehow typed "well" when I should have typed "RO" in my post above. It is my RO that measures 6.08 pH, and I have corrected the above post (with comment).

For what its worth, my well water (with whoppingly high alkalinity at 436 ppm) measures a nearly neutral pH of 7.2.

 

[Ceaver]

Forgive me, all, if this is getting a little tangential, but I think this conversation will probably (hopefully?) help the OP solve his water/pH problem.

Please correct me where I'm wrong:

So the pH of water is determined by the presence of H+ and OH- ions, which contrubite to acidic and basic pH, respectively. The alkalinity refers to the buffering capacity, which is the capacity to "absorb" H+ and OH- ions that are introduced, and therefore protect against pH swings. This is related to why Bru'n Water has you add acid to reduce the alkalinity of your sparge water, right, because the acid "uses up" the alkalinity buffer that's in your sparge water and gets its pH lower.

Grains, especially darker ones, must somehow add H+ ions to your mash liquor, which is why the pH drops during the mash. However, if that drop isn't enough, then we add some acid to the mash water as well, to get the drop into the desired range. RO water doesn't tend to have much alkalinity, as you have pointed out, so this needs to be taken into account in the calculations. For instance, when I compared my two water profile creations from tap and RO--again, using Bru'n Water--it had me add acid for the tap batch, but not for the RO batch (typical IPA grain bill and water profile). Would this be because the RO batch had less alkalinity (i.e., buffer) to begin with, as Yooper pointed out, so the pH was more easily swayed?

So what then is the net effect when there's an additional variable in the mix, such as lots of dissolved CO2 gas in the RO water? It doesn't have much buffering capacity to begin with, and the CO2 reacts with molecules to produce an excess of H+ ions, which results in crazy low pH to begin with (this part, at least, is fact and not conjecture). So then salt additions and possibly acid additions are introduced, as well as the grains, all of which would tend to lower pH, presumably through some kind of contribution of H+ ions through some reactions? If the water profile, resulting from the salt additions, doesn't end up with enough alkalinity (or hardness, as Bru'n Water calculates?), can this result in overshooting the predicted drop in pH?

Btw, I've noticed that Bru'n Water asks for pH and alkalinity of source water on the source worksheet, UNLESS you're using purely RO water, which is just entered into the water adjustment worksheet with the estimated properties of RO water (i.e., near pure). Therefore, it seems Bru'n Water isn't accounting for differences in RO water, such as high amounts of dissolved CO2, which produces H+ ions, which will eventually "use up" some of (a lot of?) the buffering capacity that is added through the salt additions?

I hope that makes sense, and that someone can help me and others understand the process a bit better.

Thanks in advance!

 

[Silver_Is_Money]

This would best be asked in the Brew Science forum, where AJ DeLange will have a chance to see it and give you a reliable answer.

 

[mabrungard]

I'm curious, where on the Water Report Input sheet does Bru'n Water ask for pH and Alkalinity? The only place that I know of is for the Alkalinity Conversion tool and that information is not used anywhere else in the program. You have misinterpreted the program.

Water pH is virtually inconsequential in the mash due to the strong buffer system created by the malt. However, there is ONE place in Bru'n Water where water pH is used. That is on the Sparge Acidification sheet where there is no strong buffer other than the water's alkalinity. That is the one place that water pH does have a minor effect on the amount of acid you should add to your sparging water.

 

[Ceaver]

I don't have the spreadsheet in front of me at the moment, but I thought I recalled that the water input sheet, where you enter results from a lab analysis, was where it asked for pH and alkalinity, or perhaps it was total hardness. Obviously you know better than I, and now that you mention it, I am recalling that it is the sparge water treatment sheet that asks for those metrics. Sorry, I'm at work and trying to recall the whole spreadsheet from memory.

I apologize for apparently hijacking the initial thread, though I do hope the OP found some use in it. I have posted my question about excess H+ due to dissolved CO2 in the brew science forum, as suggested, and will continue to trouble shoot whatever may or may not be there...

Cheers!

 

[Silver_Is_Money]

For all practical purposes, alkalinity and bicarbonate are interlocked, with a 50/61 molecular weight and valence relationship (rounded), so if a program asks for the input of one of these it is effectively asking for the other as well.