I experienced exactly the same thing. I made a pils recently where I really concentrated on the water, and it was the nicest looking break I’ve gotten in nearly 400 batches.
Another follow-up question: Is residual alkalinity (RA) really most important during mashing? How concerned should I be about it with regard to my final, post-boil wort?
Mash and boil pH matter. But if the mash pH is optimal, the boil pH is generally fine as well. The boil pH can end up much higher than the mash pH if you use lots of high residual alkalinity sparge water.
Kai
I can believe that, pils malt in general seems to have the most protein of any base malt I’ve used.
I’d agree with that. But I’d used several bags of the same malt from the same lot and hadn’t experienced a break like that until I got my water dialed in.
I’m finding that residual alkalinity is only a component to understanding and predicting a desirable mash pH. The beer color versus residual alkalinity recomendations that I’ve made in the past and many water calculators use, are woefully inadequate.
It turns out that the variation in grain acidity that Kai deciphered over a year ago is very key to the refinement in our ability to assess what might happen in the mash before we actually brew. To brewers that don’t have pH meters and the time or inclination to fine tune their brewing water, there is the potential that better water calculators can be devised.
Another thankful property of our brewing grists appears to be its tendency to buffer the over application of either gypsum or calcium chloride and not push mash pH too low. I’ve complained in the past about brewers that espouse creating water with negative residual alkalinity. My research suggests that the mash buffers prevent these mineral additions from pushing pH down. So, that doesn’t matter too much. If you want to create negative RA brewing water, it is OK, but it doesn’t really do anything extra for the mash.
Mash water chemisty is still very complicated, but hopefully we will move beyond the misinformation that is out there now and devise tools that a regular brewer can apply. I’m trying and I know there are others.
That sounds interesting. But i did find that calcium and magnesium salts do lower the pH. Maybe not at the rate suggested by the residual alkalinity formula but still fairly linear up to at least up to a calcium hardness of 800 ppm as CaCO3, which is well above what brewers would add.
Kai
Kai,
That is an interesting finding, but possibly I’m misunderstanding you. You’re telling me that you’re depressing the residual alkalinity to around -400 (this assumes there is maybe 150 ppm HCO3) and the pH continued to drop? Did the slope of the pH per RA relationship became much shallower around the low 5 range? I would be surprised to hear that the phosphate buffer system would allow the pH to drop like it does in the upper 5 to 6 range (ie, the slope of that line is the same in the upper range as the low 5 and under range).
The data is here: http://braukaiser.com/documents/effect_of_water_and_grist_on_mash_pH.pdf
Page 7, Figure 10.
Kai
Unfortunately, the figure does not disprove what my original contention was. Possibly I stated it incorrectly.
The buffer system in the mash prevents the pH from dropping much lower than the low 5 range. Adding a bunch of calcium or magnesium in order to reduce RA into the negative range has little effect. That is a good thing.
Maybe Kai could continue the experiments he presented in that excellent paper and see if my contention is incorrect? I think that something other than a Ca or Mg vs. phosphate buffer interaction is needed to bring the pH lower than the low 5 range (ie acid).
The point I’m trying to make is that it appears to me that a normal mash is naturally incapable of dropping below about 5 without adding an external acid. (PS: I see that some dark cyrstal & roast malts do have enough acidity to drop below 5, but those are used sparingly in a normal mash).
Good work, Kai.
Martin,
Thanks for the compliments on my work.
It’s possible that the curve becomes non-linear at some point. In fact it has to run into saturation since there is only limited amount of phosphate available and when there is too much calcium the calcium is not the critical substance anymore
But, I’m not sure how much further I want to take the water research. While each rock that is turned reveals more questions I do want to stop at some point and shift my focus to other aspects of brewing science which is why I don’t think I’m going to rerun many of these experiments unless we find a practical brewing question that needs answers.
One experiment I do want to rerun, though, is the acidity testing of malts. Let’s see how happy NB or MoreBeer will be when someone orders 2-4 oz of each malt they sell :). Maybe I should contact them upfront. Bob Hanson from Briess offered me to send me samples as well. Maybe I should take him op on that as well.
Kai
This is all good and sounds really interesting, buuuut , most of us are not chemist and I can only speck for myself
you guys are getting extremly technical for the average homebrewer that needs some guidence
with making his or her bers better,
We are not brewing on a large scale .
I read this forum alot , very seldom chime in and water quality has been a question in my mind .
This is way too technical at least for me.
What can I add or do for water that is low in calcium .
I guess I need to start checking PH levels more ???
Thanks for bringing this up. This has been on my mind on occasions. Sometimes a very simple post may lead to a rather technical discussion that is largely irrelevant or even confusing for the OP. However, many interesting discussions are started this way. Usually the OP’s question is answered within the first few posts though.
I don’t want to discourage us from going off on tangents but would like to address these concerns since a large number of home brewers will be confused buy the more technical discussions. Should we be more aggressive in splitting threads? So far we have only done this on rare occasions where a discussion on a totally different topic was started. In this case the technical discussion is still on topic and wouldn’t fit that criteria.
I might split this discussion off this thread if it gets some traction.
Kai
As the OP ;), I have to say I’ve really enjoyed where this thread has gone. I’ve gained exactly the information I was looking for and have significantly improved my understanding of mash/water chemistry (while acknowledging that we don’t all agree with how these things work, e.g., the buffering power of certain grain bills). I’m happy to say that I’ve got a revised approach to adding mineral salts that is based on better data than I had before. I used my revised process for an oatmeal stout session last weekend and will be using it for a schwarzbier this weekend. Incidentally, by paying more attention to my mash RA for the stout, I noticed a mash efficiency bump. Could have been random, but it could have been due to a more favorable conversion environment, namely a higher RA.
There are 2 sides to this coin…I fond that it’s too unusual for me to get lost in the discussions and just wish for a simple “do this” answer. OTOH, even when that happens, I find that by reading the discussions my understanding increases each time. I think splitting off the technical discussions would mean that less of that learning takes place. It’s not difficult to just skip over the stuff that makes my brain hurt!
I think a good tactic would be to start with reading Palmers chapter on water:
http://www.howtobrew.com/section3/chapter15.html
That will give you a basic overview of what is significant.
Also, a couple years ago Bill Pierce wrote an article in either BYO or Zymurgy which, for me anyway, was a good starting point to dive deeper into water chemistry. Unfortunately I don’t remember or have a link to it, perhaps someone else here will.
I, too, don’t feel that there’s any need to split off the “uber-techno” parts of these kinds of discussions. They’re very interesting and informative and, if you get overwhelmed, it’s easy enough to just ignore and proceed on.
I agree with Denny. Some of this was over my head, but I still learned something that I probably would not have, had the topic been split. Thanks
Question one, add a teaspoon of calcium chloride. Thats probably around 3g.
Question two, no need. Just look at your hot and cold break, if it gets more pronounced when you add that calcium salt, you can bet you improved your mash pH.
Don’t split the thread. Newbies can skim or skip over the uber-geeky stuff and glean the info again at a later date, if interested.
Several years ago, when I first read John Palmer’s book How to Brew, I skimmed over the water chemistry and adjusting your mash pH chapters. I remember thinking to myself: “That’s just overkill! You don’t need pH meters, and water chemistry, and stir plates, and Erlenmyer flasks, and temp controllers for your fridge. And, come on, yeast is yeast…!”
Well… I get it now.
One day, hornets nectar, you’ll understand it, too. It takes time and effort.
Stick with the AHA forum, and join a homebrew club if you don’t already belong to one. Ask a ton of questions. Read the books and magazines. Re-read them periodically. Brewing is complicated and nuanced enough that you can’t understand it all at once. I think you’ll like the homebrewer community–we’re a pretty friendly and generous bunch.