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General Category => All Grain Brewing => Topic started by: Pawtucket Patriot on January 20, 2011, 09:07:39 PM

Title: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 20, 2011, 09:07:39 PM
For the past several years, my SOP re: mineral salt additions has been to use CaCO3 and/or gypsum to raise pH (I use lactic acid to lower pH, when necessary). Recently, I brewed an APA with what I figured would have a nice malty backbone to compliment the hops. I didn't add any mineral salts to the mash because it wasn't necessary to hit a pH of 5.2-5.3 (measured with ColorpHast strips). I determine whether mineral salt additions are necessary based on the estimated SRM of the beer, which works very well for pH purposes.  However, my water is quite soft and without any mineral salt additions, the APA tastes a bit thin -- not with respect to mouthfeel, but with regard to malt flavor. I am wondering how to marry the concepts of adding mineral salts for flavor and adding them to adjust pH. For example, I think my APA would have benefitted from a CaCO3 and gypsum addition for flavor purposes. But based on the projected SRM of the beer, I'm concerned that doing so would result in my mash pH being too high. Is it ok to add salts that increase pH while also adding something like lactic acid to keep the pH in check?

Incidentally, my water report is the first one listed in my post here: http://www.homebrewersassociation.org/forum/index.php?topic=1887.msg26087#msg26087

And my grain bill for my APA (5 gals) was:

7.5 # 2-row
1 # light Munich
.50 # caramel 20L
.50 # victory
.25# carapils
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 20, 2011, 09:51:58 PM
Gypsum lowers pH right?

I try and use my pH adjustment additions to get me close to a good flavor profile.  Really when you think about it your first runnings aren't too far from the final boil volume, so you're going to be pretty close.

When I have enough SO4 and Cl and at the right ratio, if I need more pH lowering I resort to lactic acid.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 20, 2011, 10:17:53 PM
I think gypsum raises pH.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: denny on January 20, 2011, 10:39:48 PM
Nope, gypsum lowers pH.  You can add stuff like gypsum and CaCl2 to the kettle for flavor if you don't want to affect your mash pH.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: jlap on January 20, 2011, 10:40:48 PM
+ 1 for gypsum lowering mash pH.  I think you should check your sources again...

If you are lacking malt character in your APA I doubt it has to do with a Ca++ or SO4-- shortage.  If anything, chloride or sodium would help with that.  I suspect the problem is elsewhere.  

One way of dealing with taste vs. mineral additions is to add salts to the kettle instead of the mash if they aren't necessary for pH adjustment.  Getting the right pH is the most critical thing though I also try to get 50ppm Ca++.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 20, 2011, 10:53:17 PM
Good info. Thanks!  Time to rethink how I use mineral salts.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 21, 2011, 01:37:56 PM
So how does this sound for a game plan going forward?

1) Continue adjusting my mash pH as I have been doing (with CaCO3 to raise, lactic acid to lower).  This has worked well for me; I haven't had pH issues with this method.

2) Depending on the style I'm brewing and the flavor profile I'm going for, add any additional mineral salts to the boil kettle at the beginning of the boil.  For example, for German Pilsner, I only need to add lactic acid to my mash to lower the pH slightly.  But I want to add some calcium and a very slight amount of gypsum to get the water profile closer to that of Munich water.  So, I would add the mineral salts to the kettle at the very beginning of the boil.

I will be using the EZ Water Calculator online to evaluate whether I need to add mineral salts and how much I should add.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 21, 2011, 02:40:24 PM
you can always add gypsum/calcium chloride in balance with chalk. I.e. you want to add them such that the residual alkalinity of the water remains the same. If you do this the pH lowering ability of the calcium is offset by the pH raising ability of the chalk.

Kai
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 21, 2011, 03:26:28 PM
Sounds like a plan Paw, as long as you have adequate calcium in your mash and you don't need to add too much lactic acid to get the pH right.  I've been told not to exceed 5ml per batch lest it might start to show up in the flavor as tartness.  Or maybe it was 5ml/gallon.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: jeffy on January 21, 2011, 03:44:23 PM
So how does this sound for a game plan going forward?

1) Continue adjusting my mash pH as I have been doing (with CaCO3 to raise, lactic acid to lower).  This has worked well for me; I haven't had pH issues with this method.

2) Depending on the style I'm brewing and the flavor profile I'm going for, add any additional mineral salts to the boil kettle at the beginning of the boil.  For example, for German Pilsner, I only need to add lactic acid to my mash to lower the pH slightly.  But I want to add some calcium and a very slight amount of gypsum to get the water profile closer to that of Munich water.  So, I would add the mineral salts to the kettle at the very beginning of the boil.

I will be using the EZ Water Calculator online to evaluate whether I need to add mineral salts and how much I should add.

That's almost exactly what I did with my last batch of Dort Export.  Lactic acid for mash pH and then salts in the boil for "flavor".  It worked out pretty well with good mash efficiency and beer reminiscent of the classic style.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 21, 2011, 03:47:44 PM
Follow up question: at what point in my brew day process is the Cl:SO4 ratio most important?  During the mash?  Or is it more a mineral balance that affects the yeast (where the post-boil mineral composition is most important)?

tomsawyer, when I use lactic acid, I only add 2.5 mL to my mash, which usually involves an infusion volume of somewhere in the neighborhood of 10-14 qts (2.5-3.5 gals).

Also, when you say "adequate calcium in your mash," can you explain why?  I thought it was most important to have adequate calcium for the yeast (which would be more dependent on calcium levels in the post-boil volume).  I guess what I'm asking is when mash pH is correct, how important is the mineral composition during that phase of the brewing process?
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 21, 2011, 03:56:28 PM
I've been told not to exceed 5ml per batch lest it might start to show up in the flavor as tartness.

5 ml per 5 gal batch sounds about right. It's about 4.5 % acid malt for a 4 kg (~9 lb) grist.

Kai
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 21, 2011, 04:00:50 PM
Thanks Kai I was having trouble remembering that rule of thumb.

Paw the time to worry about the ratio is when you drink the beer, its a flavor issue.  Sulfate enhances bitterness, chloride enhances malt flavors.  Beers with a balance can benefit for a balanced ratio, although I think you should consider what the threshold and upper levels are when formulating.

You can do all your flavor additions to the kettle, it just seems parsimonious to me to use the acidifying salts to bring me close on my mash'es pH and calcium needs, and get the flavor profile close at the same time.  But the stuff isn't expensive so either way is fine.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: narcout on January 21, 2011, 08:03:22 PM
Also, when you say "adequate calcium in your mash," can you explain why?

Calcium can assist with enzyme activity in the mash.

Although, I've mashed with very low calcium levels and not had any issues with conversion.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 21, 2011, 08:10:07 PM
I believe alpha-amylase needs calcium as a cofactor.  Typically you want 50ppm Ca in your mash.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: jlap on January 21, 2011, 08:11:05 PM
Besides having enough Ca for good conversion, I noticed a big difference in the clarity of my wort after hot break and final beer when I started boosting Ca levels into the 50-75ppm range in the kettle.  Not sure of a cause-effect but maybe someone else can say something about that...
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 21, 2011, 08:26:56 PM
Hmm. I don't have much calcium in my water and haven't had any conversion issues. I suppose there's probably some calcium in the grain itself though.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 21, 2011, 08:51:10 PM
Besides having enough Ca for good conversion, I noticed a big difference in the clarity of my wort after hot break and final beer when I started boosting Ca levels into the 50-75ppm range in the kettle.  Not sure of a cause-effect but maybe someone else can say something about that...

I've observed this too.  Might be more due to the pH issue than the presence of calcium.  Bring the pH closer to the isolelectric point of a protein and it helps it drop.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 21, 2011, 09:28:40 PM
I read about positive correlation between calcium and protein coagulation via a mechanism that is different from simply changing the pH.

The first chapter on this page (http://books.google.com/books?id=zV9bpyykNtMC&lpg=PA122&ots=FggxFctnL8&dq=Larger%20particles%20are%20favoured%20by%20cationic%20flocculants&pg=PA122#v=onepage&q&f=false) of Brigg's book makes a mention of a correlation between calcium and protein coagulation. But that's all I was able to find so far.

When it comes to beer clarity, the formation of calcium oxalate in the beer can also create haze. Calcium oxalate is not sufficiently precipitated in the fermenter when there are inadequate levels of calcium present in the beer.

Kai
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 21, 2011, 09:50:08 PM
Could also be that the proteins are in fact charged and the salts screen these charges, allowing more hydrophobic interaction that results in coagulation.

All I know is, when I started just adding a couple grams of calcium chloride I got much more of that egg drop soup look in my kettle.  The effect was quite dramatic, and pushed me into learning more about water chemistry (which I was purposely avoiding for a long time).
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: denny on January 21, 2011, 10:04:50 PM
All I know is, when I started just adding a couple grams of calcium chloride I got much more of that egg drop soup look in my kettle.  The effect was quite dramatic

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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 22, 2011, 06:50:06 PM
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?
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 22, 2011, 07:24:08 PM
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
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 22, 2011, 07:27:23 PM
All I know is, when I started just adding a couple grams of calcium chloride I got much more of that egg drop soup look in my kettle.  The effect was quite dramatic

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.

I can believe that, pils malt in general seems to have the most protein of any base malt I've used.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: denny on January 22, 2011, 08:53:13 PM
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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: mabrungard on January 22, 2011, 09:37:12 PM
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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 23, 2011, 02:47:04 PM
My research suggests that the mash buffers prevent these mineral additions from pushing pH down.  So, that doesn't matter too much.

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
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: mabrungard on January 25, 2011, 03:58:22 PM
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). 
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 25, 2011, 04:01:27 PM
The data is here: http://braukaiser.com/documents/effect_of_water_and_grist_on_mash_pH.pdf

Page 7, Figure 10.

Kai
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: mabrungard on January 25, 2011, 04:22:46 PM
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. 
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 25, 2011, 04:41:29 PM
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
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: hornets nectar on January 25, 2011, 04:42:09 PM
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  ???
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Kaiser on January 26, 2011, 03:52:48 PM
I read this forum alot , very seldom chime in and water quality has been a question in my mind .

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
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Pawtucket Patriot on January 26, 2011, 04:05:22 PM
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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: denny on January 26, 2011, 05:01:34 PM
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!
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: davidw on January 26, 2011, 05:32:27 PM
. . .  and water quality has been a question in my mind .
This is way too technical at least for me.

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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: Hokerer on January 26, 2011, 05:46:20 PM
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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: dogismycopilot on January 27, 2011, 12:36:54 AM
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
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 27, 2011, 01:14:32 AM
What can I add or do for water that is low in calcium .
I guess I need to start checking PH levels more  ???

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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: richardt on January 27, 2011, 04:42:16 AM
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.
Title: Re: Adding mineral salts for both flavor and pH adjustment purposes
Post by: tomsawyer on January 27, 2011, 01:20:42 PM
Water was the last ingredient I tackled, and it was in stages.  I started by just adding some calcium chloride, figuring calcium was good for the mash.  Turns out it had a rather noticeable effect on my hot and cold break, so I was enticed into learning the whole enchilada.  My beers are the clearest they've ever been, but I haven't been using high enough levels of the flavor components to know if I'm improving flavor.