Water treatment for a multi step mash

[Blackdirt_cowboy]

I am starting to brew some traditional german beers using multi step mashes. Currently my mash tun is a converted cooler, so the only way to accomplish this is boiling water infusions. I use bru’n water to adjust my water profile. When calculating the amount of minerals to add, do I need to estimate the total amount of water it will take to get me to mash out and enter that as the mash volume? Then enter the remainder for the sparge volume?

On a side note, what mash thickness should I target for the protein rest? I normally mash with 1.25 quarts/pound of grain, but obviously, with a step mash, this ratio will change throughout the mashing process. Perhaps I should look at it as how much water should I leave to sparge and work backwards from there to calculate my infusion amounts.

 

[cactusgarrett]

I can't answer to the first part, as I don't typically do steps. However, I think BruNWater (maybe just the free version?) would only utilize numbers for the overall mash. Just talking it through here: the important part of the water treatment is the pH of the mash, so it should be important to have that correct upon initial dough-in (for the first rest); that's what I've done when I actually have done step mashes. However, any subsequent infusions will throw that overall pH/water content off unless the infused water is treated, as well. Good question, and I'm curious as to the best answer.

When i have done step mashes (including protein), I've started no lower than 0.9 qt/lb and ended anywhere between 1.5 and 2.0 qt/lb. I'm a double batch sparger, though, so that requires some adjustment to normal practices, like reducing the number of batch sparges and/or reducing the sparge volume. If you've got a bigger grain bill, it might just be an issue of resigning yourself to the idea that you won't be able to sparge as much as you typically do.

Planning ahead will help you figure out your plan better than doing it on brew day, so you're on the right track.

 

[ajdelange]

I am starting to brew some traditional german beers using multi step mashes. Currently my mash tun is a converted cooler, so the only way to accomplish this is boiling water infusions.

One of the simplest approaches to water treatment in brewing (and some of the commercial operations are adopting it) is to add acid to the entire volume of water you intend to use to the point that the pH is at the desired mash pH. Your water's alkalinity, wrt mash pH, is now 0 and you enter that into your calculator in order to determine how much additional acid you need to accommodate the alkalinity of the malts. Should the answer be that you need some alkali things become a little more complicated as you don't want to add acid only to neutralize it with alkali. In such cases you would need to separate out the volume to be used for sparging and dilute it with source water until the effective acid addition is reduced by the amount of the alkali required for 0 alkalinity water. This really isn't at all hard to do but I am sure it sounds confusing and in such cases it may be better to proceed in the more usual fashion which is as you have suggested...

I use bru’n water to adjust my water profile. When calculating the amount of minerals to add, do I need to estimate the total amount of water it will take to get me to mash out and enter that as the mash volume? Then enter the remainder for the sparge volume?

On a side note, what mash thickness should I target for the protein rest? I normally mash with 1.25 quarts/pound of grain, but obviously, with a step mash, this ratio will change throughout the mashing process. Perhaps I should look at it as how much water should I leave to sparge and work backwards from there to calculate my infusion amounts.

This is the problem with multi step mashes. At each step you require a larger volume than the last step because you are trying to warm a larger mass (grain plus the strike water plus the mass of each previous infusion's water). You should make a simple Excel spreadsheet in which you can track the temperature rise with infusions. You may well find that you cannot reach your goal by this method but in any case you will want to strike with as little water as possible in hopes of reaching mashout before the cooler overflows or the water to grist ratio is so low that you will be boiling all day to concentrate the wort. Many find that some of the steps need to be carried out with external heat.

 

[DurtyChemist]

What I do is add the total volume of water needed to mash to my kettle and modify that water to what I want. Add the first step, bring water to a boil, add second step, bring water to a boil etc.

 

[mabrungard]

One of the simplest approaches to water treatment in brewing (and some of the commercial operations are adopting it) is to add acid to the entire volume of water you intend to use to the point that the pH is at the desired mash pH. Your water's alkalinity, wrt mash pH, is now 0 and you enter that into your calculator in order to determine how much additional acid you need to accommodate the alkalinity of the malts.

Since I don't want readers to look at only the first part of the message above and think they're done, I'll emphasize an important qualifier.

Water pH prior to adding the malt is NOT likely to be equivalent to your mashing pH. For light-colored beers, the pH of the acidified water is likely to be well below 4. The water's alkalinity is effectively below zero and has a surplus of hydrogen protons. When the malt is added to the water, the buffers and alkalinity in the malts will then bring the wort pH back into the targeted range (assuming you've calculated your acid addition properly).

In the case of dark beers, the water pH may actually be greater than your targeted mashing pH.

My message is for brewers to understand that water pH prior to the introduction of malt, is an inadequate guide for predicting mashing pH.

 

[ajdelange]

Since I don't want readers to look at only the first part of the message above and think they're done, I'll emphasize an important qualifier.

This does take some thinking about.

Water pH prior to adding the malt is NOT likely to be equivalent to your mashing pH.

It is if you set it to your desired mash pH following the procedure I gave in the post i.e. just add acid until you reach the desired mash pH. You don't, of course, need to do this for RO water. Its alkalinity is already effectively 0.

For light-colored beers, the pH of the acidified water is likely to be well below 4.

Not if you acidify to 5.4 (or whatever your target pH is).

The water's alkalinity is effectively below zero and has a surplus of hydrogen protons.

It is if you acidify to below 4.5 but then we aren't advocating that. We are advocating acidifying to the target mash pH. I think perhaps you missed that important point. At mash pH the alkalinity of the water is 0 with respect to mash pH. The point being that the proton deficit of the water is then taken care of. That's why you enter 0 for alkalinity in any calculator you are using.

When the malt is added to the water, the buffers and alkalinity in the malts will then bring the wort pH back into the targeted range (assuming you've calculated your acid addition properly).

Again this makes me think that you have misread the suggestion such that you think I'm advocating calculating acid addition considering water and grain and then adding that to the mash water. I'm not.

My message is for brewers to understand that water pH prior to the introduction of malt, is an inadequate guide for predicting mashing pH.

It's not the whole story, of course as one needs to know the malt alkalinities too. But as noted above and in the original post, setting the water pH to the target pH removes it from further consideration as its alkalinity is now 0 (WRT mash pH) thus simplifying calculation of additional acid requirements. If one uses a robust pH estimation algorithm (totting up proton deficits and surfeits), entering 0 for alkalinity and if one feeds the program good data re the malts he will get a good estimate of the acid required to be added to the mash in addition to that already added to the water.

Try thinking of it this way. Under the usual procedure you send some water off to Ward labs and they come back with a report as to how much acid you need to add to a liter of it to get it to pH 4.5 (this is the alkalinity in ppm as CaCO3 divided by 50). A robust program then calculates how much acid is needed to get a liter of it to target mash pH (a not so robust program knows this is about 90% of the alkalinity). It then multiplies that by the liters of water to get the proton deficit for the water and adds that amount of acid to the acid amounts it calculates for getting the malts to target mash pH.

If we simply acidify the water to the desired mash pH we have effectively done the titration, calculations and addition all in one step without any calculations. The water is taken care of and we can now turn our attention to the malts.

A big advantage of doing things this way is that it automatically compensates alkalinity differences between what is in your Ward Labs report and the alkalinity of the water before you in the HLT. This could be significant for those whose water alkalinities vary appreciably over time (as many peoples' do).

 

[mabrungard]

So you've just advocated a 2-step process that has no real benefit since it ends up in the same condition as if calculated? In addition, it relies on pH measurements at both points to guide the acid additions? I think I'll stick with a proper calculation for mash acidification.

 

[ajdelange]

So you've just advocated a 2-step process that has no real benefit since it ends up in the same condition as if calculated?

I think a major benefit is that you automatically compensate for variations in alkalinity as you are incorporating the alkalinity titration into the water treatment regimen thus accounting for secular variations in that parameter relative to what the operator thinks his alkalinity is based on a Ward Labs report. It also moots the question as to what end point pH was used by the lab.

In addition, it relies on pH measurements at both points to guide the acid additions?

No, just the measurement that insures that the water has reached the desired mash pH.

I think I'll stick with a proper calculation for mash acidification.

The wording suggests that something is improper which implies that you still don't understand what is being suggested. Please be sure that you do before you make a judgement as to whether it simplifies things or not. Apparently Chico brewing has decided that it is the way to go as they do it on at least some of their beers. Of course whether you see a benefit on no is entirely up to you. These ideas are offered for those who see the potential benefit to the point where they will try things out. I'm not suggesting that people necessarily have to do this to make better beer. It won't do that as the end pH should be the same - well I guess it will in the cases where alkalinity varies but you can always handle that by doing an alkalinity check before each brew. Is the alkalinity check followed by the calculation simpler than just acidifying to target pH? Up to the user to determine that for himself.

 

[Blackdirt_cowboy]

I’m not real sure where to go from here. My source water is terrible for brewing, sky high alkalinity. I’ve got an RO system that I’ve been using and building my water up from there. The pH of my RO water is 6.5. AJ, are you suggesting to add acid to that to bring it down to target mash pH, for example, 5.3? Surely when I add the salts back into the water, the pH will change, won’t it? Won’t the grains also affect the pH?

For now, my plan is to input all the water required to perform the step mash into bru’n water as the total mash water and treat it. Then I’ll treat the remainder of the sparge water seperately. This is what I’ll do this weekend when I brew, unless I can get clarification on what AJ is suggesting.

 

[ajdelange]

I’m not real sure where to go from here. My source water is terrible for brewing, sky high alkalinity. I’ve got an RO system that I’ve been using and building my water up from there. The pH of my RO water is 6.5. AJ, are you suggesting to add acid to that to bring it down to target mash pH, for example, 5.3?

No. As it says in No. 6, you don't need to do that for RO water. If you tried to you would probably undershoot as RO water has nearly 0 alkalinity and only a tiny amount of acid would be needed.

Surely when I add the salts back into the water, the pH will change, won’t it?

. If you add CaCl2 that contains some Ca(OH)2, as some does, or Ca(OH2) or NaHCO3 there will be a small change in pH but we assume here, as in all other calculations, that these impurities are not present.

Won’t the grains also affect the pH?

Well yes. That is why you have to do the remainder of the calculations with alkalinity set to 0. You would do the same thing here with your RO water.

For now, my plan is to input all the water required to perform the step mash into bru’n water as the total mash water and treat it. Then I’ll treat the remainder of the sparge water seperately. This is what I’ll do this weekend when I brew, unless I can get clarification on what AJ is suggesting.

To be perfectly clear on this, my suggestion does not apply to RO water.

 

[Blackdirt_cowboy]

I missed where you said it was not necessary to do this with RO water. It makes perfect sense now. Thanks for all the help.