Just need some opinions...water for stout

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Pugs13

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Hey guys I put together this water profile using Bru'n Water's Black Balanced Desired Water Profile. This is for a Dry Irish Stout using 100% dilluted RO water calcs. Just need some opinions on the final numbers. Thanks :mug:

Calcium - 80
Magnesium - 8
Sodium - 12
Sulfate - 53
Chloride - 46
Bicarbonate - 169

Hardness - 234
Alkalinity - 140
RA - 78
SO4/CL Ratio - 1.15
pH - 5.5
 
For Dry Irish Stout as typified by Lewis's (Ashton) recipe in Lewis's (Michael) book in the AHA series that is too much alkalinity. I brew that recipe with tap water with alkalinity of about 80 and come up with a mash pH which is a little high (5.5 or so). I don't think you need to add acid here if you back off on that alkalinity. I'd guess 50 would be just about right based on my experience.
 
For Dry Irish Stout as typified by Lewis's (Ashton) recipe in Lewis's (Micahel) book in the AHA series that is too much alkalinity. I brew that recipe with tap water with alkalinity of about 80 and come up with a mash pH which is a little high (5.5 or so). I don't think you need to add acid here if you back off on that alkalinity. I'd guess 50 would be just about right based on my experience.

Thanks. Would you say 5.5pH is pretty standard for a darker/malty beer? Also, I have searched around to try and gain some knowledge on the sulfate to chloride ratio but have not really come up with anything showing the way that it is displayed in Bru'n Water. If it is 1.1 is that balanced? If it is 1.65 what is that? What if it's 2.45 or something to that nature? I understand the effects of each mineral and what they do...I don't understand the way it's portrayed I guess. Thansk again.
 
Yes, I think 5.4 - 5.5 is the 'sweet spot' for most beers with perhaps ales at the lower end and lagers at the higher and I think you can go outside that range without too much detriment.

I don't place much stock in the sulfate/chloride ratio thing. If I want dry, prominent, harsh bitterness I add sulfate. If I want round, mellow, sweetish beer with good mouthfeel I add chloride. The ratio comes out to be whatever it comes out to be (which is 0 in most beers I brew but that's my personal taste). I know that if I have to brew with water that boasts 200 mg/L sulfate I can't 'fix' it by supplementing the chloride to the 200 mg/L level. I know I have to get rid of the sulfate.

Thus I don't understand the ratio thing either. The chemistry of brewing water and the mash tun are very intricate and brewers often grasp in desperation at things that they think might simplify this aspect of their brewing. Setting RA according to color was one of those and this ratio is another. Of course if I tell you x and y or x and y/x I am giving you the same information so the ratio may be a useful piece of information for you. Just don't use it as a design parameter.
 
Thanks. Would you say 5.5pH is pretty standard for a darker/malty beer? Also, I have searched around to try and gain some knowledge on the sulfate to chloride ratio but have not really come up with anything showing the way that it is displayed in Bru'n Water. If it is 1.1 is that balanced? If it is 1.65 what is that? What if it's 2.45 or something to that nature? I understand the effects of each mineral and what they do...I don't understand the way it's portrayed I guess. Thansk again.

I know you didn't ask me. Anyways, I don't know about standard pH for darker beers, but I've seen some people say they prefer a slightly higher pH (e.g. 5.5, compared to 5.4) for darker beers because they feel it mellows the roasty edge a bit. Also, as far as the chloride to sulfate ratios, don't worry about those too much. Certainly don't worry about specific ratios like 1.1 or what not. I go by the general rule of adding only calcium chloride for malty or balanced beer, and a little calcium chloride (25-50 mg/L chloride) and a quite a bit of calcium sulfate (100+ sulfate) for a hoppy beer.
 
I was asking whomever had an explanation, procedure, experience or opinion. I appreciate the help. The problem I am having with this is that I cannot get my pH up to where I want it without having at least 75-80 in my alkalinity. When I fall within the target water for black balanced the pH is not where I want. Does RA really play a role here? The profile I posted above was pretty close to London on the Water Charts that Bru'n Water provides...do they really use that water in London, not sure but...it is what it is I guess...
 
I was asking whomever had an explanation, procedure, experience or opinion. I appreciate the help. The problem I am having with this is that I cannot get my pH up to where I want it without having at least 75-80 in my alkalinity. When I fall within the target water for black balanced the pH is not where I want. Does RA really play a role here? The profile I posted above was pretty close to London on the Water Charts that Bru'n Water provides...do they really use that water in London, not sure but...it is what it is I guess...

Well, as AJ stated, he brews his dry stout with 80 alkalinity, so perhaps you want to try that.
 
I've gone up to about 95-100 alkalinity for an oatmeal stout I brewed recently, that had a large amount of specialty grains. It turned out with a good background of that coffee flavor AJ often mentions when he talks about his stout.
 
The problem I am having with this is that I cannot get my pH up to where I want it without having at least 75-80 in my alkalinity. When I fall within the target water for black balanced the pH is not where I want.
How are you measuring pH? Strips tend to read 0.3 low and I'd guess they are even harder to read with a dark colored mash. The inexpensive meters home brewers use tend to be unstable (but you can beat that with frequent cal checks and, if required re-cals).

Does RA really play a role here?
RA was another one of those straws home brewers have grasped at. RA is very useful for its intended purpose: comparing water supplies but takes a back seat to alkalinity which is the main 'enemy' of the brewer. The reason for this is that the phytin calcium reaction usually produces only a small portion of the acid required to set proper mash pH. The majority either comes from roast or caramel malts (or barley) or is added by the brewer.

The profile I posted above was pretty close to London on the Water Charts that Bru'n Water provides...do they really use that water in London, not sure but...it is what it is I guess...

I'll leave it to Martin to fully explain the philosophy behind the profiles he chose to include but I believe the intent is to give a profile which is physically realizable (many published profiles aren't) and that is reasonably representative of the associated region. This profile seems entirely suited to stouts and porters but should probably have the alkalinity reduced for a dry stout. I don't speak to the other types because I don't brew them.
 
The bottom line is that the color-based water profiles include first-guesses for the calcium and bicarbonate content needed to brew a particular class of beers. The actual grist will determine if those levels should be elevated or reduced to produce a desirable mash pH. An alkalinity of 80 might work with some recipes and be insufficient in others. That is what these tools are for, so you don't have to listen to someone's opinion of what worked for their water and their recipe. You will have something that is scientifically- and empirically-based to assess what direction you might need to go. YMMV.
 
I have played around a bit with it. Here are some new numbers.
Ca - 58
Mag - 7
Sodium - 15
Sulfate - 54
Chloride - 45
Bicarbonate - 103

Hardness - 173
Alkalinity - 85
RA - 40
Ratio - 1.21
pH - 5.4
 
I'd go with the 2nd profile and see what that gets you. Once you brew the beer again you can make adjustments.

Kai
 
I guess I am just still trying to understand the Alkalinity and RA for stouts. I have seen some off the chart numbers that seems to work for others but now I am trying to get down to 80-85 Alkalinity while maintaining a pH of 5.4-5.5, which only leaves me with 39 RA?? Is that right? Then you look at other profiles and some of the Bicarbonates are crazy as well is 103 suitable...Sorry just trying to understand...want to have a nice water recipe to use every time I brew this beer.
I will try this second profile above and see what happens. Again, thank you for all your help.
 
Ca 58/20 ~ 2.9 mEq/L Ca Hardness
Mg 7/12.15 ~ 0.576 mEq/L Mg Hardness
Effective hardness ~ 2.90 + 0.576/2 = = 3.188
Alkalinity 85 ~ 1.6 mEq/L
RA = 50*( 1.7 -3.188/3.5) = 39.5
4o is close enough for government work.

As I noted in a previous post RA really doesn't have a lot to do with it. If you look at a plot like this one: http://www.wetnewf.org/pdfs/kolbach-ra.html you'll see the RA's of the waters of various cities and the assumption is often made that if I want to brew stout I need to have water with RA smilar to that of Dublin but there are two Dublins on that chart one with an RA of 25 and one with an RA of 130. Which is right? Probably neither. What yoy need is to get the mash pH in the right window. If you use a profile like your most recent one you will probably be in the right window.

I know it is difficult. You have the option of relying on a model (and we all know the situation with respect to models) or peoples' experiences and we all know the potential problems with that. You must really experiment. A test mash is a good idea. I asked earlier how you were measuring mash pH. That is very important. Lots of people use strips, conclude that their mash pH's are too low and dump in alkali (strips seem to have a pretty consistent bias of 0.3 pH to the low side).

As to some of the crazy RA, hardness and alkalinity numbers you see: if they are off the chart (i.e. the one linked to above) consider them 'off the chart'.
 
I asked earlier how you were measuring mash pH. That is very important. Lots of people use strips, conclude that their mash pH's are too low and dump in alkali (strips seem to have a pretty consistent bias of 0.3 pH to the low side).
I use a pH probe the checker from HANNA. I do the 7.01 and the 4.01 before every brew session and recalibrate if need be.

As to some of the crazy RA, hardness and alkalinity numbers you see: if they are off the chart (i.e. the one linked to above) consider them 'off the chart'.

That's awesome...haha...love that response. This water stuff has been a struggle but little by little I am getting it.
 
Ca 58 ~ 1.04 mEq/L Ca Hardness
Mg 7 ~ 0.58 mEq/L Mg Hardness
Effective hardness ~ 1.04 + 0.29 = 1.43
Alkalinity 80 ~ 1.6 mEq/L
RA = 50*( 1.6 - 1.43/3.5) = 60
How did you get 40?

40 is what it is saying on Bru'n waters RA cell. If I try and change that it falls below that and/or it raises my Alkalinity above 80 closer to 90
 
AJ, both of those Dublin profiles are probably correct. Much of the city gets its water from the Wicklow Mountains to the south of the city. That water has relatively low hardness and alkalinity. The north part of the city gets water from a carbonate area. The areas to the west of the city are very much in a carbonate landscape and would be quite subject to high alkalinity.

To everyone else, there is no correct RA that you can assign to stout or porter or pils, etc. Its dependent upon the grist. As AJ points out, you can create a grist that could be brewed quite well with somewhat low alkalinity. Conversely, you could create a grist that requires much more alkalinity. It depends.
 
This is what I am working with.
12gal. batch

13lbs - Maris Otter
2lbs. - Flaked Barley
1lbs./12oz. - English Roasted Barley (500 srm)
12oz. - Chocolate Malt (350 srm)

Total Grains: 17.50lbs.
SRM - 34.7
IBU - 36.5
Est. ABV - 4.3%

Maybe that will help a little more...
 
You have about half again as much dark stuff in there as the recipe in the monograph so you can expect the pH to be lower - perhaps 5.4 but you should still be OK. That is, of course, given that your black malt/barley aren't unusually acidic. Your pH meter will tell you that. It is always a good idea to do a test mash before brewing a recipe using dark grains for the first time.
 
You have about half again as much dark stuff in there as the recipe in the monograph so you can expect the pH to be lower - perhaps 5.4 but you should still be OK. That is, of course, given that your black malt/barley aren't unusually acidic. Your pH meter will tell you that. It is always a good idea to do a test mash before brewing a recipe using dark grains for the first time.

Yea I played around with it a little by taking out some of the roast/black barley out but I start loosing that nice rich black color. Would you suggest just taking out or lowering the chocolate? How much of a difference would scrapping the 12oz. really make? If I lower the roast/black malts but lock in a good water profile and pH is spot on, could that make up for taking out some grain by contributing to color and taste? Or just leave what I got, go with a pH of 5.4 and see what happens?
 
It's hard to say because I didn't use materials identical to those you have in hand. Taking out some of the black stuff will obviously raise pH and reduce color but it's hard to predict. In lab experiments I found 10% roast barley gave me mash pH of about 5.55 and 30% 5.19 so shifting around a few percent shouldn't make that much difference. WRT color I have found that 10% roast barley gives me colors that varied from 64 to over 80 for different batches. That's plenty 'black' as far as I'm concerned.
 
It's hard to say because I didn't use materials identical to those you have in hand. Taking out some of the black stuff will obviously raise pH and reduce color but it's hard to predict. In lab experiments I found 10% roast barley gave me mash pH of about 5.55 and 30% 5.19 so shifting around a few percent shouldn't make that much difference. WRT color I have found that 10% roast barley gives me colors that varied from 64 to over 80 for different batches. That's plenty 'black' as far as I'm concerned.

Sounds good. I think I may just brew a batch this weekend and see how it goes. I will shoot for pH 5.4. Another thing I wanted mention was that after reading about your thoughts on "chalk" I did not use any of that in the water profile, I used real small amounts of pickling lime, gypsum, ca chl, Epsom.
 
It's hard to say because I didn't use materials identical to those you have in hand. Taking out some of the black stuff will obviously raise pH and reduce color but it's hard to predict. In lab experiments I found 10% roast barley gave me mash pH of about 5.55 and 30% 5.19 so shifting around a few percent shouldn't make that much difference. WRT color I have found that 10% roast barley gives me colors that varied from 64 to over 80 for different batches. That's plenty 'black' as far as I'm concerned.
I thought there was a visual threshold that is a lot higher than that anyhow. I don't remember it off hand and and my googlefoo is weak today.
 
All in all...I am still not understanding if you take for instance Bru'n Water "Black Balanced" and fall within all the "Target Water Adjustments" by using the different salts why that is not considered to be perfect for brewing the style you are wanting to brew using 100% RO water. This is of course done only if you don't care about what the Hardness, Alkalinity, RA, and Ratio turns out to be after you plug the numbers in. I would think that as long as you get within reason of what the targets suggest and your pH is spot on then go for it...but now there is talk about keeping Alkalinity around 50-80...its impossible to get that low and keep your Bicarbonates in check along with pH wanting to be in the 5.5 range. Unless I am completely missing something. Again, if I play around with the numbers this is what I get if I stay within the guidelines of the Target profile. It comes out to be close to the London profile on the charts..and I get 5.5 for pH but on the other hand...Alkalinity is well above 50-80...my head is going to explode...

Ca - 65
Mag - 9
Sodium - 8
Sulfate - 47
Chloride - 35
Bicarbonate - 142

Hardness - 197
Alkalinity - 118
RA - 66
Ratio - 1.35
pH - 5.5
__________________
 
I thought there was a visual threshold that is a lot higher than that anyhow. I don't remember it off hand and and my googlefoo is weak today.

There is no such thing as black beer. It always lets a little light through. Black beers, such as stouts, are actually red as you can demonstrate to yourself by shining a flashlight through some. If you have to get down to 1/2" in the bottom of the glass before you see any light coming through then you have a pretty dark beer.

What looks black in a glass depends on several things such as the size of the glass, the nature of the light, whether it is backlight and so on. Generally speaking I guess I'd call anything more deeply colored than 30 SRM or so black.
 
There is no such thing as black beer. It always lets a little light through. Black beers, such as stouts, are actually red as you can demonstrate to yourself by shining a flashlight through some. If you have to get down to 1/2" in the bottom of the glass before you see any light coming through then you have a pretty dark beer.

What looks black in a glass depends on several things such as the size of the glass, the nature of the light, whether it is backlight and so on. Generally speaking I guess I'd call anything more deeply colored than 30 SRM or so black.
30 is the number my memory had queued up but I didn't want to throw it out there since I couldn't find a reference. Everyone is allowed to have their own criteria but throwing in more black barley just to drive the color lower probably isn't worth the flavor shift at some point.
 
I would think that as long as you get within reason of what the targets suggest and your pH is spot on then go for it...but now there is talk about keeping Alkalinity around 50-80...its impossible to get that low and keep your Bicarbonates in check along with pH wanting to be in the 5.5 range. Unless I am completely missing something.

It is entirely possible to hit pH 5.5 with no alkalinity whatsoever. I do it every time I brew lighter beers. It is also quite possible to hit pH 5.5 with alkalinity of 80 in a stout with 10% roast barley. I do it every time I brew stout. I think you are putting too much faith in spreadsheets and calculators. They provide valuable guidance for someone wishing to brew a particular style of beer for the first time but they are based on a model as to how Maris Otter behaves and have assumed characteristics for roast barley built in and etc. If you use a roast barley that has twice the acidity of the roast barley that the model builder used then you will get a very different result than what the spreadsheet tells you. This is why you ask around for hard data. I'm giving you hard data. But if you brew using a roast barley that is half as acidic as the one I use you are going to get a different result from the one I got. So you have to make your best guess and brew. Then you have really good data: your own and you can use that to guide you in the future.

All you have to do to brew a decent Irish stout from RO water is add a tsp of calcium chloride to each 5 gal or if you want some hop punch, half a tsp of calcium chloride and half a tsp. of calcium sulfate. You should, of course, check mash pH and if it comes out at 5.1 add some bicarbonate next time. But it isn't likely to come out at 5.1. But if it come out at 5.4 you can stop obsessing on alkalinity and concentrate on the amounts of calcium chloride and gypsum because it is quite probable that you will find some schedule for those other than half a tsp of each that gives you a beer you like better.
 
It is entirely possible to hit pH 5.5 with no alkalinity whatsoever. I do it every time I brew lighter beers. It is also quite possible to hit pH 5.5 with alkalinity of 80 in a stout with 10% roast barley. I do it every time I brew stout. I think you are putting too much faith in spreadsheets and calculators. They provide valuable guidance for someone wishing to brew a particular style of beer for the first time but they are based on a model as to how Maris Otter behaves and have assumed characteristics for roast barley built in and etc. If you use a roast barley that has twice the acidity of the roast barley that the model builder used then you will get a very different result than what the spreadsheet tells you. This is why you ask around for hard data. I'm giving you hard data. But if you brew using a roast barley that is half as acidic as the one I use you are going to get a different result from the one I got. So you have to make your best guess and brew. Then you have really good data: your own and you can use that to guide you in the future.

All you have to do to brew a decent Irish stout from RO water is add a tsp of calcium chloride to each 5 gal or if you want some hop punch, half a tsp of calcium chloride and half a tsp. of calcium sulfate. You should, of course, check mash pH and if it comes out at 5.1 add some bicarbonate next time. But it isn't likely to come out at 5.1. But if it come out at 5.4 you can stop obsessing on alkalinity and concentrate on the amounts of calcium chloride and gypsum because it is quite probable that you will find some schedule for those other than half a tsp of each that gives you a beer you like better.

I tried using that method of just adding a tsp of either and it seemed even with the right pH the beer tasted great out of the fermentor but when carbonated it lacked in taste, it was a bit dull/watered down and maybe even a little minerally. I thought maybe by playing around with pH and different salts it would help aid in this problem. I will try that last water profile with roughly 80 alkalinity and 40 RA and see how that turns out. Thanks again for all the support. I appreciate it more than you know.
 
I tried using that method of just adding a tsp of either and it seemed even with the right pH the beer tasted great out of the fermentor but when carbonated it lacked in taste, it was a bit dull/watered down and maybe even a little minerally. I thought maybe by playing around with pH and different salts it would help aid in this problem. I will try that last water profile with roughly 80 alkalinity and 40 RA and see how that turns out. Thanks again for all the support. I appreciate it more than you know.

So this was your opinion of the beer created using just RO water and a tsp of either gypsum or calcium chloride? If they were stouts, then your result is typical. The reduced mash pH does enhance the fermentability of the resulting wort and adds a tartness. The low pH also reduces the extraction of color and flavor from the roast malts. A beer like this just doesn't taste like a stout should. That increased fermentability comes at the cost of breaking down more of the less fermentable sugars and dextrins and that reduces your perception of the beer's body and mouthfeel.

Feel free to try AJ's recommendations, but I'm pretty sure that you'll find that an appropriate level of alkalinity is quite beneficial for the flavor and other perceptions of a beer like this. It might need 80 ppm alkalinity or it might need a lot more. That is what Bru'n Water is there to help you with.
 
So this was your opinion of the beer created using just RO water and a tsp of either gypsum or calcium chloride? If they were stouts, then your result is typical. The reduced mash pH does enhance the fermentability of the resulting wort and adds a tartness. The low pH also reduces the extraction of color and flavor from the roast malts. A beer like this just doesn't taste like a stout should. That increased fermentability comes at the cost of breaking down more of the less fermentable sugars and dextrins and that reduces your perception of the beer's body and mouthfeel.

Feel free to try AJ's recommendations, but I'm pretty sure that you'll find that an appropriate level of alkalinity is quite beneficial for the flavor and other perceptions of a beer like this. It might need 80 ppm alkalinity or it might need a lot more. That is what Bru'n Water is there to help you with.

You know I might just try with an alkalinity of about 90 just so I can keep my pH up around 5.4. I mean I was hoping to get to 5.5 but seems like that would mean I would be in the 100's for alkalinity and that may be stretching it...but then again maybe not...haha
 
The reduced mash pH does enhance the fermentability of the resulting wort and adds a tartness. The low pH also reduces the extraction of color and flavor from the roast malts. A beer like this just doesn't taste like a stout should.

Then I guess you are saying that Guiness doesn't taste the way a stout should taste because what you are describing is a pretty good description of an Irish stout including the ones I've brewed using Lewis's recipe. So I'm a little confused here. I always thought Guiness was pretty good stuff but I do remember putting this beer in a contest and getting a low score back with the comment 'This tastes like Guiness' which I took as a compliment though it clearly wasn't meant as one. But the part about color extraction is off. I consistently measure 60 - 80 (and so does Guiness BTW). And I guess you are saying that pH 5.5 is too low. How high should he go to get a 'real' stout? And what should the color of a real stout be?
 
Ah, thank you for asking. Yes, Guinness is a less than pleasant stout. Acrid, ashtray flavor and the only reason it has any body is the large dose of beta glucans from the barley. Another interesting component is that the nitrogen addition to Guinness dry stout is probably in part to reduce the acidity fostered by straight carbonation. Guinness is truly one of those strange animals where odd parts are added on until the creature is functioning. It does taste good enough, but it is a compilation of work-arounds and compromises. Better Irish stouts include Beamish and Murphys. Better stout can and is made with more alkaline water.

Both Beamish and Murphys are made by the same brewer in Cork, IRE where the water has significantly more alkalinity than the southside of Dublin where the Guinness James Gate brewery is located. Interestingly, some of the finest stouts and porters in the world are made (not surprisingly) in the Midwest where alkalinity is king. Using that terrior label, this is the result of that dumb luck where recipe and water mesh well. If I recall correctly, an Ohio brewery (Weasel Boy) won gold in either WBC or GABF with their stout. I've tasted it and can attest that it blows a beer like Guinness into the weeds. Do not mistake marketing success for good taste. If marketing success was the criterion, then Bud is the best tasting beer in the world.

I'm sorry that you received that 'tastes like Guinness' comment, but I have to say I would be one of the judges that may respond in the same way. Guinness is not a pleasant stout and is not the pinnacle of the style. Better stouts are made with more alkalinity.
 
Well...it seems as if this has turned into a pretty good conversation. Tell you what...I will brew this next stout with higher alkalinity and higher pH and compare it to my existing recipe of 1 tsp of calcium chloride. From there I can determine if there is a difference. I will keep you posted. BTW I think Guinness is great and is my go to beer when I am at the pub...I agree it could be more but I think many out there can agree that Guinness was their gateway drug that got them into either craft beer or home brewing. I have won contests with my 4.3% stout with only adding 1 tsp additions...but being who I am, I am always seeking to make things better...which I know I don't have the best stout but it could be better...I have the advantage of using Irish whiskey infused oak cubes that add a little more flavor and complex into my stout but without that I know it should be more flavorful I guess. So all in all, I agree with both of you but we'll see what happens...
 
Going back to the discussions of going through the trouble of dissolving chalk to emulate certain styles I was under the impression that it was considered a waste of time because when you corrected your mash pH it would precipitate out anyhow. Did I come away with a wrong impression there? I just used a calculator and dumped some baking soda in and then neutralized it with enough acid to get the mash pH back to where it had been and the alkalinity and RA are both higher now.
 
Interesting comments. They got me to haul Lewis off the shelf and have a quick glance through. I'm posting one diagram here, a spiderweb plot comparing Guiness, Beamish and Murphy's, neither of which I like nearly as much a Guiness - de gustibus non est disputandem I suppose. I'm not quite in agreement with the fellow that wrote "The beer [from Cork] is by far the worst I have ever tasted." but I'll take a Guiness over a Murphy's or Beamish any time it's available. But that's my personal taste. I'll come back to that.

Anyway there are substantial differences in the hoppy, sweet and fruity/estery axes none of which you mentioned as being responsible for the supposedly poor quality of Guiness. Astringent/phenolic variation is much less than these as is roasted.

I also found the acidity comment interesting as while it is true that Guiness does contain somewhat more titratable acidity than the other 2 Murphy's pH is lower at 3.97. And while on the subject of pH (to which the palate responds - it doesn't care about the buffering behind it)
I'm also attaching the cumulative pH distribution of the 21 stouts Lewis studied. The data show the median pH to be 4.25 and the mean 4.02. Stouts are sour beers. Note that the pH of Guiness at 4 puts it in the bottom decile whereas Beamish at 4.3 is in the 40%tile and Murphy's is off the chart to the left at 3.88.

As to the alkalinity issue. Lewis brewed 9 experimental beers in which he varied the amounts of roast barley and used 3 different waters: DI, DI + CaSO4 and simulated Dublin. Rather than paraphrase I'll quote:

"We found that when additional roasted material was added it increased the roasted and burnt flavor and aroma characters - not a very surprising result. Furthermore, the more alkaline water consistently increased the total sensory bitterness of the stouts, though as far as we could tell it did not much change the sensory quality of that bitterness. These two effects were quite marked, but no other consistent sensory effect of brewing water showed up in these trials."

But that's sensory. The pH's of the beers made with more alkaline water were higher (that's a note to Kai if he is reading this).

So higher alkalinity water doesn't make a better stout. It makes one that Martin prefers. This is classic confirmation (or cognigtive) bias. It is hard as hell to fight that and win (I can't). Guiness isn't bad beer or a bad example of a stout. It is typical (look at the other spider diagrams and the PC plots in Lewis's book if you have it. Nor, though he calls Guiness "the quintessential stout" does he say it is the best stout. It is a typical stout. I prefer it to Murphys or Beamish and I prefer the qualities that Martin doesn't like - in particular the dry tartness with the hint of coffee and of course the head. But I won't tell anyone that he has to like it or that Murphy's and Beamish aren't good beers. They can't be as they enjoy pretty wide markets.

Stouts.jpg


StoutpH.jpg
 
How much of the pH in the final product is related to carbonation? Doing a quick google I see references to bicarbonate playing a buffering roll in the process. Would this play a role in what volume of CO2 you wished to carb at?
 
Carbonic acid is an acid and clearly the more you dissolve the lower the pH is going to be but it is a weak acid with first pK = 6.38. This is more than 2 units from the pH of all but two of the beers Lewis studied. Thus the pH of the beer will be determined mostly by the acids secreted by the yeast and less so by the carbon dioxide.
 
So...back to the old saying...I will have to just experiment. I didn't mean to stir up such a ruckus...but definitely some good insight into Stouts and most importantly I have learned some things as well.
 
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