Potential Water Pitfalls in All Grain Brewing

[toxdoc49]

Basic question: Should the pH of the water or the pH of the mash be measured, since adding grain to the water will alter the pH depending on the grain. Meaning, do you start the mash and then measure pH and adjust accordingly or adjust the pH of the strike water prior to mashing?

 

[day_trippr]

Chasing mash pH in real time is a losing proposition in many ways (temperature maintenance a big one). The goal is to have calculated the minerals/salts and acid required - given the grain bill and water volumes needed - in advance, so hopefully if there is any pH error it's small.

I use Bru'n Water for this, but there are other tools.

I take a pH reading 10 minutes after dough-in (then cooled to 68F).
If the mash pH was over or under I note it for the next time I brew that recipe...

Cheers!

 

[toxdoc49]

Chasing mash pH in real time is a losing proposition in many ways (temperature maintenance a big one). The goal is to have calculated the minerals/salts and acid required - given the grain bill and water volumes needed - in advance, so hopefully if there is any pH error it's small.

I use Bru'n Water for this, but there are other tools.

I take a pH reading 10 minutes after dough-in (then cooled to 68F).
If the mash pH was over or under I note it for the next time I brew that recipe...

Cheers!

Thank you for that information. I did wonder how it would be possible to have an acceptable pH range especially if using multi step infusion. It seems that one does not want to wait 10 minutes to know the pH when using the multi step method. So I intend to begin pH measurement after dough in, unless pH is not as important for the protein rest step

 

[ajdelange]

Unfortunately, mash pH does not stabilize for about 20 minutes so we really don't have much choice in the matter. You can take readings before 20 minutes and with a little practice predict pretty closely from a 10 minute reading what the 20 minute reading will be but to get the equilibrium mash pH (or close to it) you will have to wait 20 minutes or more. The object is, as stated in #32, to have made additions that will get you close to the desire pH as verified with a test mash. Small errors in the equilibrium pH should be noted for adjustment of the amount of acid (or base) used to set pH in future brewings of this beer. Large errors should be corrected and while they will not completely remove problems that have been caused by improper mash pH fully at least you will be going into the kettle and fermenter with pH in the right range.

 

[mabrungard]

I settled on testing pH on 15-minute intervals during the mash. I find that the first pH result at 15 minutes into the mash is only a few hundreths off the following measurement results. When I used to collect at the 10 minute mark, the difference was larger. I'd say that AJ's recommendation for about 20 minutes is close enough.

 

[toxdoc49]

Ok, 20 minutes. Given that there is an initial protein rest step for 10 minutes at 122 F, what should be done for pH there? Or will it not affect the later steps where the temperature is raised?

 

[mabrungard]

Ok, 20 minutes. Given that there is an initial protein rest step for 10 minutes at 122 F, what should be done for pH there? Or will it not affect the later steps where the temperature is raised?

If you've applied the measures recommended from a competent brewing water chemistry tool, the pH should be close enough. I don't chase pH after I've applied those measures. I just monitor pH and log the results in my record so that I can alter my target in future brews.

 

[ajdelange]

Ok, 20 minutes. Given that there is an initial protein rest step for 10 minutes at 122 F, what should be done for pH there? Or will it not affect the later steps where the temperature is raised?

A malt's influence on mash pH depends on its DI mash pH and a couple of buffering terms which describe its resistance to pH change as protons are added (from acid) or taken away (absorbed by a base). The DI pH depends on temperature. The buffering terms less so. Thus when a malt's acid/base characteristics are measured it is done at some temperature reasonably representative of mash conditions. At the same time the rate of change of DI mash pH with temperature is measured. In order to determine the amount of acid needed for a particular malt for a particular pH one uses the formula a*(pH - pHDI) + b*(pH - pHDI)^2 + c*(pH - pHDI)^3 in which pH is the pH of interest (target pH), pHDI the DI mash pH and a, b and c the buffering coefficients. Strictly speaking this malt characterization is accurate only for the temperature at which the measurements of a, b, c and pHDI were made. But as the expansion is about pHDI we can obtain the proton requirement (or surfeit) at any temperature simply by changing the pHDI value by the amount of temperature glide (as I like to call it). Thus, from measurements ( a complete set would be pHDI, a, b, c, T at which these were measured and the glide i.e. rate of change of pHDI per degree temperature) made at, say 40 °C we can obtain the deficit at 50 °C (122 °F), 25 °C (room temperature) or any other temperature of interest. Temperature of interest is an input parameter to a spreadsheet that implements the pH control/prediction algorithm correctly. Unfortunately, none do this but then none that I am aware of implement the deficit formula properly either.

Now since one is going to check mash pH at room temperature the obvious temperature to enter into the calculator is room temperature. Thus one could make a proper spreadsheet or calculator which implements the formula properly by shifting each malts pHDI to room temperature if it were understood that all estimated pH's are for room temperature and, in the control mode, all acid additions are for target pH as measured at room temperature.

As pHDI, a, b, c, T, and ∂pHDI/∂T are all measured 25 minutes after the sample is 'doughed in' it also has to be understood that results obtained using them only strictly apply to measurements of mash pH made 25 minutes after strike. The idea here is that if the glide theory reasonably represents reality (and it appears to but this does need to be investigated further) it doesn't matter if you dough in in the cold, at a ß-glucan rest temperature, at a protein rest temperature, or at a saccharification rest temperature.

 

[toxdoc49]

Went back to the bible (John Palmer). Also looked at a few other sites. Best to adjust pH after doughing-in the mash. No one really knows in advance what will happen to pH when grains are added unless one has the experience. Since I do not, The basic approach will be to measure pH after grain addition to strike water and have something on hand to adjust it if needed. Yes, a water report is a good idea to get. I think the bottom line is that one can make 'good' beer without necessarily fretting over pH, but it would be a lot better beer if pH is paid attention to and one knows the composition of the water being used. The commercial breweries are certainly aware! There are so many possible grain combinations that of course pH should be measured after grain and water are well mixed. Since this particular recipe I have calls for the option of multi-step infusion (and I am going to try it), I will probably be constantly monitoring pH especially the first protein rest step.

 

[ajdelange]

The problem with the approach you are proposing to follow is that by the time you get a stable mash pH reading (20 - 25 min), calculate the correction needed (how will you do that if you don't know the buffering?), measure out the acid or base add it to the mash and get it mixed in it is really too late to obtain the major benefits of proper mash pH (but it is better than doing nothing). There is a simple way around this, however, and that is to mash a small portion of grains using scaled water treatment. If you miss your target, try again with a small correction to the acid amount. From the change in pH brought about by the change in the amount of acid you can calculate the buffering and thus the amount of acid required to hit the target. Scale that back up to the full mash and proceed. This is some extra work but well worth it. As you note, with experience you won't need the test mash. Your notes from previous brewing of this beer will direct you though you may still make some small changes based on those notes. If your water is stable (use RO or the 0 effective alkalinity method to insure that it is) seasonal variations in the malts shouldn't have much effect.

 

[toxdoc49]

I appreciate the time everyone took to address my questions. Very helpful advice!

 

[Buckeye_Hydro]

I just bought property with a well that hasn't been used for years. What has to be done to get an accurate test sample for the well?

We always advise folks NOT to buy residential property that has a well without making the deal contingent up the well producing suitable drinking water. How would you know?
http://www.buckeyehydro.com/drinking-water-test/

 

[toxdoc49]

That part is true, you have to know that the well is producing water. Assuming it is, typically a plumber will get it up and running and shock it with chlorine, then you will run all the faucets for a time to clean out the pipes. Once the chlorine has gone from the system you would test the water just like any other supply. You can test it at the tap and also from an outside faucet or hydrant if you have one.

 

[day_trippr]

fwiw, said well might not be the sole potable water source on said property...

Cheers!

 

[toxdoc49]

But the water can be potentially good. Mine is unfortunately hard water, so I have a softener syatem, but that makes it difficult to use for brewing. I can bypass the system and have the well water itself tested and may be able to use that, at least get the composition of minerals in the water

 

[Buckeye_Hydro]

And if its not good, then run the softened water through an RO.

 

[toxdoc49]

I also have an RO system, just not set up for large volumes.

 

[Bobby_M]

I also have an RO system, just not set up for large volumes.

That can be remedied with a bucket and a float valve. 20 bucks max.

 

[Buckeye_Hydro]

That can be remedied with a bucket and a float valve. 20 bucks max.

And an Auto shut off valve.

I also have an RO system, just not set up for large volumes.

Remember that any membrane 24 gpd thru 200 gpd with fit in a standard residential housing - so you can speed your system up if desired.

 

[ajdelange]

A couple of tips:

If a softener is involved be sure to test the water at the input to the softener. It is trivial to compute the ion content of the water at the output of a softener from the input values but not the other way around.

When testing a well be sure to get the bacteriological test done (or do it yourself). The county, city, state or your insurance company may have something to say about this.

[Edit: There used to be instructions here for shocking your well yourself but as there was potential for personal injury (or in extreme cases death) if not done right I thought I'd better remove them. Call a plumber]

 

[toxdoc49]

I ended up brewing an all grain recipe from NB (German alt). I violated a few rules here (used pH test strips for one). The grain had some dark malts in it so the pH was decreased and i did not add anything (I buy spring water, I have not had my well water tested but I know it is hard water so I don't use it). I usually only learn by trial and error and do know the advice on this site is good. Besides probably not using enough sparge water I came close to the stated OG; I will just have to see how it turned out. Yes I dove right in with multi-step infusion and full 5 gallon boil!

 

[MT's AZ Ale Haus]

What would be the harm in using RO water with no additives.
Will it effect the wort tast or will it reduce efficiency?

 

[ajdelange]

You will find the beer thin in body and flavor from lower than desirable chloride content. I you like the effects of sulfate on hops bitterness perception and with respect to dry finish you will find those attributes missing. You will not obtain the benefits of calcium WRT enzyme protection, runoff clarity, oxalate precipitation etc.

 

[mabrungard]

What would be the harm in using RO water with no additives.
Will it effect the wort tast or will it reduce efficiency?

AJ's comments are valid. However, it won't necessarily thin the body. The flavor can be duller and disinteresting with no mineralization, but that could be OK in some styles...and a real detriment in others. RO with minor additions of calcium chloride and/or gypsum is an easy way to avoid dullness.

 

[ajdelange]

There may be cases where chloride content is decoupled from body/fullness (though I can't think of one) so I'll change my statement to "You will probably find the beer thin in body and flavor..." I do remember an experiment I did with a series of Kölsch brews in which I wanted to see "how low can you go" on the CaCl2. Below a certain level the thinning effect was so dramatic that perhaps it incorrectly set into my mind this notion that chloride and body are related. OTOH it doesn't take one long to find statements like this

"The chloride ion is believed to promote a palate fullness, sweetness, or mellowness within the flavor profile of beer."

in articles backed up by references like

Bernstein, Leo, and Willox, I. C. “Water.” In The practical brewer, ed. Harold M. Broderick, 13–20. Madison, WI: Master Brewers Association of the Americas, 1977.

Kerwin, Larry. “Water.” In MBAA practical handbook for the specialty brewer, volume 1: Raw materials and brewhouse operations, ed. Karl Ockert, 7–12. Madison, WI: Master Brewers Association of the Americas, 2006.

Kunze, Wolfgang. “Raw materials.” In Technology brewing and malting, 2nd ed., 69–73. Berlin: VLB Berlin, 1999.

It does say "believed to". I'm a believer.

Others can find out whether they are believers or not with some simple taste tests with a beer made with low chloride water (e.g. PU) and a salt shaker.

Such discussions usually prompt me to mention that I have been around so long ("how low can you go" is a clue) that I can remember when salt shakers were set along the bar and the guys that I, at that time, considered to be old timers, would regularly dump it into their beer.

 

[Todd Terczynski]

I was told by many that you should mix RO water with regular water 50/50 so you still had necessary Ca and Magnesium for hardness and RO water helps with pH. Makes a project balance. I personally haven’t seen a noticeable difference in taste either way

 

[Jag75]

I was told by many that you should mix RO water with regular water 50/50 so you still had necessary Ca and Magnesium for hardness and RO water helps with pH. Makes a project balance. I personally haven’t seen a noticeable difference in taste either way

Think it depends on your water report like AJ said .

 

[BrewinInPA]

Any problem with using a little lemon juice to adjust mash pH? I almost always have fresh lemons on hand for cocktails, and I doubt the small amount needed would affect the beer's flavor too much.

 

[mabrungard]

Any problem with using a little lemon juice to adjust mash pH? I almost always have fresh lemons on hand for cocktails, and I doubt the small amount needed would affect the beer's flavor too much.

Citric acid (in lemon juice) has a low taste threshold and you would likely taste it in your beer. If you like lemony beers, give it a go. I find that most beer drinkers prefer 'beer' flavored beers.

 

[madscientist451]

I don't brew on a regular basis, sometimes I brew 4 times a month, sometimes I don't brew anything for 4-6 months. (cider and wine season + hot summer months), so I never got a PH meter because you're supposed to keep the probe/sensor in a solution and I figure I'll forget about it, let it dry out and ruin it. So I just brew with tap water and use 50/50 tap/distilled for lagers. All the beer gets consumed and I haven't heard any complaints, but is there a way an occasional brewer can use a PH meter without worrying about ruining it?