Water chemistry Primer questions/advice

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grathan

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It says to sharpen hop bitterness use additional sulfate. Sulfate wasn't mentioned in the baseline additions. One of the other posts refers to Gypsum as being (calcium sulfate). Is it add gypsum to increase hop bitterness?

It says for more sweetness add chloride. Is chloride the same as the aforementioned calcium chloride dihydrate?
 
It says to sharpen hop bitterness use additional sulfate. Sulfate wasn't mentioned in the baseline additions. One of the other posts refers to Gypsum as being (calcium sulfate). Is it add gypsum to increase hop bitterness?

Sulfate isn't in the baseline because lots of people don't like sulfate. The guideline does recommend some gyspsum (CaSO4.2H2O) for those doing British beers because they are commonly brewed with fairly gypseous water.

It says for more sweetness add chloride. Is chloride the same as the aforementioned calcium chloride dihydrate?
Yes - CaCl2.2H2O.

motobrewer said:
what about really hard and salty water?

Na - 211
HCO3 - 352

The real problem here is the alkalinity which is about 285 for a water with this much bicarb. It would have to be diluted down by 9:1 to get that alkalinity down to 28 which is still pushing things a bit. I'd probably just go with RO water (but note that 90% rejection of bicarb by your RO unit would would still leave alkalinity at 28.5. Check the rejection specs that come with the unit.
 
For starting out (and probably most home brewing) GE makes an under-the-sink model which produces about 5 gallons a day. It's a little over $100 at Home Depot. Lots of guys here seem to have obtained systems for their aquaria. I personally use a Titan system.
 
Sulfate isn't in the baseline because lots of people don't like sulfate.

Hi, ajdelange,

Your comments about the taste imparted by sulfates in this, and other, posts have led me to think they could be the main problem in my beers. For the sake of having a basis for comparison, would you mind commenting on the sulfate levels in Sierra Nevada Pale Ale? I figure that's probably one of the most readily available brands for anyone reading this post. So, if you pop open a bottle of SNPA and pour a glass...do you detect that sulfates are used in their brewing process? And if so...roughly in what range? I'm hoping you say that they are either NOT present, or are only present in very low levels (which would validate my current theory, haha). But of course, I'd rather hear the truth if it's not the case :)

The problem I've been having in my (several) attempts at cloning this and other American PA/IPA's is that they come out way too bitter. People have told me to watch my sparge temps, watch my mash pH, etc. I monitor all of these things...and they are all within appropriate levels. So, at this point, there's really no where in my process that I can pinpoint--except water chemistry.
 
So, if you pop open a bottle of SNPA and pour a glass...do you detect that sulfates are used in their brewing process? And if so...roughly in what range?

I am extremely flattered that someone thinks my palate is that good! What I can do is pop open the presentation that one of their guys gave at an ASBC conference a couple of years back. Chico water is pretty low in sulfate but they dose it with gypsum to the extent of 60 mg/L sulfate. They found that that was OK if they controlled mash pH with acid but if they tired to control it with CaCl2 they 1) didn't control it very well and 2) got harsh beer. This is just more ammunition for me in my crusade to get people to control mash pH and de-emphasize mineral additions.

The problem I've been having in my (several) attempts at cloning this and other American PA/IPA's is that they come out way too bitter. People have told me to watch my sparge temps, watch my mash pH, etc. I monitor all of these things...and they are all within appropriate levels. So, at this point, there's really no where in my process that I can pinpoint--except water chemistry.

Try a beer with reduced sulfate and see if you like the result better. Control mash pH and see if you like the beer better.
 
The real problem here is the alkalinity which is about 285 for a water with this much bicarb. It would have to be diluted down by 9:1 to get that alkalinity down to 28 which is still pushing things a bit. I'd probably just go with RO water (but note that 90% rejection of bicarb by your RO unit would would still leave alkalinity at 28.5. Check the rejection specs that come with the unit.

what's the issue with RA? If i brew darker beers will that get me into an acceptable pH range?
 
I am extremely flattered that someone thinks my palate is that good!

:)

Chico water is pretty low in sulfate but they dose it with gypsum to the extent of 60 mg/L sulfate.

A quick google search tells me that this is the same as 60ppm, which is much lower than the levels I've used in the past...and therefore validates my current hypothesis (that sulfates have been harshing up my beer!).

By the way...that information about SN is awesome. I've heard Steve Dressler in interviews and I've read some of his (alleged) posts online; he doesn't seem to hold his cards too close when it comes to recipes, which is really cool. But this is the first I've EVER heard about their actual water. I emailed them a couple of months back and asked specifically about the water they use; the information I got back was vague. Still...I thought it was pretty cool that they responded.

Try a beer with reduced sulfate and see if you like the result better. Control mash pH and see if you like the beer better.

I currently do the latter...pH meter and all. I plan to try the former with my next batch using your baseline/primer approach (fingers crossed that it helps!).

Thanks again.
 
We all know that the use of dark malt was a mechanism early brewers adopted to combat high water alkalinity. The use of roast and high color crystal malts lowered mash pH but perhaps not as much as we would like by today's standards. For water with alkalinity this high you doubtless could brew a pretty good dark beer but alkalinty that high would be a real problem for a lighter beer such as a pilsner.

Now if you cut that alkalinity by 10 and try to brew a dark beer you will probably be OK but you really should check mash pH and if it is too low add some chalk to the mash.

thanks for the info. i've been brewing with ice mountain spring water previously since my water obviously sucks, and my darker beers seem to have a twang to them. i've been thinking that the relatively soft spring water is the culprit, so i wanted to try a dark beer with tap water in the mash.

with spring water my lighter bitters/ambers/ipas have been great.
 
I have very hard, highly alkline, high iron content water. My first extract batch was undrinkable; my research indicated that I could brew extract with RO water, so I brewed 12 very good batches of beer. I had my water tested by Ward Labs in preparation for going AG; diluted my brew water with about 37% RO, used the E-Z water ss to get all my ions into the acceptable range & get the Cl/SO4 ration into the "Balanced" range. Usually adding Lactic Acid, Gypsum & Epsom Salt. This worked OK for pale beers; but browns, ambers, & porters were terrible (these didn't have any Lactic Acid added). Even though extract versions of these recipes were very good. Several months ago I started reading ajdelange's posts regarding pH, Sulfates etc. The harsh bitterness he describes, associated with high Sulfates was exactly what I was tasting. I purchased some ColorPhast strips, used the NEW version of the E-Z water sheet, added CaCl2 & Lactic Acid to get the predicted pH to 5.3 & SO4 level of 38. I proceeded to brew a Nothern Brown Ale. (My measured pH was 5.4). This brew has been in the bottle for 3 weeks now, it is the best beer I have brewed so far!:ban::ban: I now have a Cream Ale fermenting that has a SO4 level of only 12, the hydro sample tasted great. So, I am a believer.
 
I have very hard, highly alkline, high iron content water. My first extract batch was undrinkable; my research indicated that I could brew extract with RO water, so I brewed 12 very good batches of beer. I had my water tested by Ward Labs in preparation for going AG; diluted my brew water with about 37% RO, used the E-Z water ss to get all my ions into the acceptable range & get the Cl/SO4 ration into the "Balanced" range. Usually adding Lactic Acid, Gypsum & Epsom Salt. This worked OK for pale beers; but browns, ambers, & porters were terrible (these didn't have any Lactic Acid added). Even though extract versions of these recipes were very good. Several months ago I started reading ajdelange's posts regarding pH, Sulfates etc. The harsh bitterness he describes, associated with high Sulfates was exactly what I was tasting. I purchased some ColorPhast strips, used the NEW version of the E-Z water sheet, added CaCl2 & Lactic Acid to get the predicted pH to 5.3 & SO4 level of 38. I proceeded to brew a Nothern Brown Ale. (My measured pH was 5.4). This brew has been in the bottle for 3 weeks now, it is the best beer I have brewed so far!:ban::ban: I now have a Cream Ale fermenting that has a SO4 level of only 12, the hydro sample tasted great. So, I am a believer.

That is great to hear; your story is similar to mine in that I first tried to get all my ions into acceptible range using the EZ water spreadsheet. The beers were drinkable for the most part except for APA's, which were just way too harshly bitter (sadly...I had to literally dump a couple of batches down the drain; there's just no way I would have served them to anyone...and I wasn't gonna waste my time choking it down for the sake of what?). I also used the newest version of the EZ water spreadsheet and had the same problem with harsh bitterness. I watch the pH (using a meter) and make sure it is within acceptible range so I know it's not that. The only thing left that I can see is the Sulfates (after reading ajdelange's posts). I think the ranges that Palmer suggests (which are used in the EZ water spreadsheet) are just well...much different from my personal tastes. Read: way too high.

I won't know for sure until I brew my next batch using this approach...but your personal account is reassuring that I'm on the right track. Cheers.
 
Can anyone recommend a good RO system or manufacturer?

wwwdotthefilterguysdotbiz

I've bought from them many times for my reef keeping hobby. They're systems are solid, customer support is great, and you can upgrade like crazy as you see fit.
 
Or dark crystal malts (but you will obviously be adding color and flavor with those too)

Any salt/mineral that adds Ca will acidify the mash, because it forces H+ into solution (they come from the malts). But I have never measured the extent of acidification from CaCl, CaSO4, CaCO3, etc. Even though CaCO3 is typically used to raise pH, in the case of a mash, it actually lowers pH b/c the malt is buffering the carbonate (which raises the pH) and the Ca are going to bond with the phosphates in the malts, releasing the H+ into solution (the mash liquor).

ghpeel - do you have hard water? Water high in carbonates? Are you just curious? Do you get city water?

Most of the time you don't have to worry much about water chemistry, unless you water is hard and high in carbonates (has a naturally high buffering capacity = pH too high). Or if you have extremely soft water and are brewing dark beers. (pH too low).

ajdelange - I love the cynicism and completely agree. Damn Na, always messing things up.
 
Any salt/mineral that adds Ca will acidify the mash, because it forces H+ into solution (they come from the malts)... Even though CaCO3 is typically used to raise pH, in the case of a mash, it actually lowers pH b/c the malt is buffering the carbonate (which raises the pH) and the Ca are going to bond with the phosphates in the malts, releasing the H+ into solution (the mash liquor).

Careful here. Remember the formula for Residual Alkalinity:

RA = alk - ([Ca]/3.5 +[Mg]/7)

where alk is the alkalinity and [Ca]and [Mg] the calcium and magnesium hardnesses. All three of these are in the same units, typically ppm as CaCO3. In those units decreasing the RA by 100 ppm as CaCO3 reduces (approximately) mash pH by 0.17. Now if you add 100 mg CaCO3 to 1L of water you have increased its alkalinity by 100 mg/L as CaCO3 (should be no surprise there) but you have also increased the calcium hardness by 100 mg/L Thus the RA is 100 - 100/3.5 = 71.4 mg/L greater than it was before and the mash pH would be expected to be 0.714*0.17 = 0.12 units higher than it was before. In words, the carbonate part of calcium carbonate raises mash pH lots more (3.5 time more) than the calcium lowers it.

Another thing to keep in mind is that it takes a lot of calcium to achieve an appreciable pH reduction. Suppose a soft water mash give a (typical) pH of 5.7 or so and it is desired to reduce this to 5.3. That's a pH drop of 0.4 and would require calcium hardness of 100*0.4/.17 = 235 ppm as CaCO3 equivalent to 20*235/50 = 94 mg/L calcium. That would be way too much for a Bohemian Pils (though perhaps not too much for a German one or an Export).
 
ghpeel - do you have hard water? Water high in carbonates? Are you just curious? Do you get city water? Most of the time you don't have to worry much about water chemistry, unless you water is hard and high in carbonates (has a naturally high buffering capacity = pH too high). Or if you have extremely soft water and are brewing dark beers. (pH too low).

My purpose out of this is that I want to use 100% RO water for cost reasons. My city water is full of chorlamines and nasty stuff.

Ideally I want to have 3-4 mineral profiles to add to the beer depending of if the beer is light/dark, hoppy/not-hoppy, malty/not-malty.

I want an Idiots Guide to Water Chemistry really. I want Ikea-style directions for additions to RO water to make a few styles of beer. I don't want to have to understand chemistry to make beer. :D

So if someone could make a recipe list so to speak, that would look like this it would be AWESOME:

"Start with 100% RO water"
"Hoppy Light beer: 1 tsp foobar, 1 tsp lactic acid (88%)"
"Dark Malty Beer: 2 tsp gypsumite sulfate, 1/2 tsp calcium something-or-other"
"Dark Hoppy Beer: eye of newt, 1 tsp calcium chloride"
 
ajdelange - your alkalinity eq. doesn't take the ions from the grist into consideration. But it works awesome for a beaker of water and some salts.

I can't give you eq. to back up my claims. Its empirical data. 3 g CaCO3 in 5 gal mash isn't going to raise the pH with my (soft, city) water. Those grains have buffering capacity, that's why your pH drops when you mix it with the water.
 
See the first post of this thread.

Ok I've re-read that, still not groking it 100%, but here's a stab at another way of listing itL:

Pilsner or soft water styles: 1/2 tsp calcium chloride, 3% sauermalt
American Pale Ale: 1 tsp calcium chloride, 1 tsp gypsum, 2% sauermalt
British Pale Ale: 2 tsp calcium chloride, 1 tsp gypsum, 2% sauermalt
Hoppy/Strong British Ale: 4 tsp calcium chloride, 2 tsp gypsum, 2% sauermalt
Porter or Stout: 1 tsp calcium chloride (no sauermalt)
Cascadian Dark Ale (hoppy): 1 tsp calcium chloride, 1 tsp gypsum (no sauermalt)

Are these right? What about Hefe's, do they fall into the soft water style?

What about: Wits, Belgians, or Irish Red's where do they fall?

A listing of all the BJCP styles and the adjustments needed to RO water to get a proper baseline would really be helpful to a lot of folks. Water chemistry is (to me anyway) by far the most complex part of brewing I've had to deal with.
 
ajdelange - that SN presentation you have must be pretty cool. Could you post it so we can download/view it?
 
Ok I've re-read that, still not groking it 100%, <duly circumcised>

Please note. The guidelines are just a starting point for those of us trying to figure out the water chemistry issue. In the end it is a 'to taste' or, if you prefer, a 'to guidelines' issue. This sticky was not meant to be a 'cover all'. My first brew using this info is a Scottish 70 that won't even go into the bottle for another week. I know, this is HBT and I should be raving about the expected results already, but I'm a patient man. The little that didn't go into the secondary went into the hydrometer tube and then me. So far so good.
 
ajdelange - your alkalinity eq. doesn't take the ions from the grist into consideration. But it works awesome for a beaker of water and some salts.

Thanks for the compliment but that equation is attributable to Kolbach - not me. You can find a translation of his paper at www.wetnewf.org (Kolbach's 1953 paper). While the 0.17 increase in pH per increase of 100 ppm as CaCO3 he observed (he actually observed in dH) is approximate it does take into account the buffers in malt. In fact it is a sort of measure of the buffering capacity of pure base malt grists.

I can't give you eq. to back up my claims. Its empirical data. 3 g CaCO3 in 5 gal mash isn't going to raise the pH with my (soft, city) water. Those grains have buffering capacity, that's why your pH drops when you mix it with the water.

If you are seeing a drop in pH when you add calcium carbonate to mash then you are measuring pH wrong. The grains do, of course, contain buffering systems but if you stress a buffer with alkalai (carbonate) pH goes up, not down. For a rather detailed explanation go to the same website and download the article "Cerevesia 2004" which goes into the phosphate and carbonate chemistry involved in this process. If you do that you will find that the main mechanism by which calcium lowers pH is precipitation of hydroxylapatite

10Ca++ + 6(PO4–--) + 2H2O &#8596; Ca10 (PO4 )3(OH)2 + 2H+

in which 10 moles of calcium precipitated releases 2 moles of hydrogen ions. Approximately 12 more moles of hydrogen ions are released as monobasic inorganic phosphate from the malt is converted first to dibasic and then tribasic phosphate for a total of 14. If the calcium comes from calcium carbonate 10 moles of calcium imply 10 moles of carbonate which require a bit less than 20 moles of hydrogen ion to lower the pH to desired mash pH. Thus there is a deficit of 0.6 mole of H+ for each mole of calcium precipitated and mash pH goes up. This is a gross simplification but the Cerevesia paper shows some results of simultaneous solution of both the carbonate and phosphate buffering systems. Under certain assumptions these models reproduce Kolbach's result. Lots of equations here, yes, but experiment confirms.


You should be aware that it is widely accepted that adding chalk to a mash raises its pH and that many brewers, home and professional, use this means for mash pH adjustment as reference to any of the many water adjustment spreadsheets will show you. While this is true if you put as much as 3 grams of chalk into a 5 gallon mash most of it will not dissolve because there simply isn't enough acid in malt to dissolve that much chalk and even if there were the reaction would be very slow. pH will rise but not to the extent that the stoichimetry might predict.
 
So I have a question regarding this.

I have figured the amounts of Calcium Chloride and Calcium Sulfate I need to add for my Pale Ale. I have this amount figured out for 3 gallons of water, 5 gallons, and 10 gallons.

I have 7 pounds of grain, so I'm going to mash with about 11 quarts of water, that'd be about 2.75 gallons. So I can just add the amount of salts I would need for 3 gallons of water to my mash no problem.

My question is--I want to treat my sparge water too so that I can have all the water in my beer have the same profile. I figure I'll sparge with about 5.5 gallons. The goal is to collect about 4 gallons of wort for my 3.5 gallon batch. So I'll need about 10 gallons of treated water (8.25 for mash and sparge plus a little extra if I need to top off, raise temps etc.)

Would it be advisable to treat all 10 gallons of water? I.e. add enough CaCl and CaSO4 for ten gallons of water (in a pot) and let it dissolve? Then I can just use that water how I please?

Or should I add the salts to the mash for 3 gallons and then treat the other 7 gallons separately?

I realize my wording is confusing but what is the best way to go about this so that ALL my water has the same profile (not just the mash).
 
Would it be advisable to treat all 10 gallons of water? I.e. add enough CaCl and CaSO4 for ten gallons of water (in a pot) and let it dissolve? Then I can just use that water how I please?

That's exactly what I do. Both of those dissolve readily in room temperature water.
 
Or should I add the salts to the mash for 3 gallons and then treat the other 7 gallons separately?

It doesn't matter, six of one, half dozen of the other. You are doing the same thing. In one its just all in one container, in the other its in two containers.
 
Cool. Thanks for the advice. I redid my calculations and actually only need 6.75 gallons of water total. 2.75 for mash and 4 for sparging. That total volume of water requires four grams of CaCL and four grams of CaSO4 to get the results I want.

So I think what I'll do is put 1.75 grams of each in the mash, and put the other 2.25 grams in my 4 gallons of water when I heat it to sparge. Mostly just because I don't have a bucket big enough to hold 7 gallons of water. But I'll also feel better knowing that at least my Mash PH will be right if the CaCl and CaSO4 don't dissolve as much as they should, or something weird like that.
 
Are you using 100% distilled water? Regardless, 4 grams of gypsum is going to be one hell of a bitter beer (the sulfate intensifies bitterness perception). This is from much experience with adding salts, esp. gypsum (its my favorite mineral! not just in terms of brewing).

Are you trying to make Burton on Trent water? What is your goal with the salt additions
(you may want to start a new thread for this question)

Also, gypsum and CaCl2 won't change the pH of water (I guess the additional Ca2+ ions could lower the pH some once mixed with the grist, maybe......)
 
Are you using 100% distilled water? Regardless, 4 grams of gypsum is going to be one hell of a bitter beer (the sulfate intensifies bitterness perception). This is from much experience with adding salts, esp. gypsum (its my favorite mineral! not just in terms of brewing).

Are you trying to make Burton on Trent water? What is your goal with the salt additions
(you may want to start a new thread for this question)

Also, gypsum and CaCl2 won't change the pH of water (I guess the additional Ca2+ ions could lower the pH some once mixed with the grist, maybe......)

According to Palmers Spreadsheet, those additions should make for a good water profile for my beer. I'm making a Pale Ale at 7 SRM.

It'll bring my minerals to this: Chloride 78, Sulfate 89. RA of -19. Perfectly acceptable for 4-9 SRM beer. That'll be nice and balanced (for the Cl to SO4) and well within the range I need. I'm using 50% distilled and 50% tap.

So according to Palmer's spreadsheet I'm good. I'll get a beer that is dry, sharp, and slightly bitter but still with a nice balance. Also, using the easy water chemistry spreadsheet (found here) it says my Mash PH will be about 5.6.

What am I missing?
 
Well sounds like nothing is going to change your mind. So brew it and see what you think. That is really the best way to learn.

Serving the beer warmer (say 50 F) will help if it ends up being too bitter to your taste.

What is your tap water profile? What does a negative RA mean?
 
Well sounds like nothing is going to change your mind. So brew it and see what you think. That is really the best way to learn.

Serving the beer warmer (say 50 F) will help if it ends up being too bitter to your taste.

What is your tap water profile? What does a negative RA mean?

My tap water is this:

Calcium 28, Sodium 20, Magnesium 8, Chloride 7, Sulfate 7, Total Hardness in CaCO3 95.

I've seen people say they add 1-2 tsps (4-8 grams) of salts when they brew with no bad effects.

I'm just curious why you think it'll be bitter if I'm also adding chloride to balance? I'm certainly open to suggestions/advice.

I genuinely want to know if there's something I'm not taking into account because Palmer's spreadsheet says I'll be okay. So am I misinterpreting the data?
 
What does a negative RA mean?

RA = alkalinity - (calcium_hardness + magnesium_hardness/2)/3.5

It is the alkalinity which is not "neutralized" by hydrogen ions released when calcium (and, to a lesser extent magnesium) reacts with malt phosphate. Distilled water has no alkalinity (well, it does actually have a wee bit but that's a technicality arising out of how it is defined and measured) so if you add even a small amount of calcium chloride or calcium sulfate these could react with malt phosphate to produce hydrogen ions which could neutralize more bicarbonate than is present. Thus, the RA is < 0.
 
RA = alkalinity - (calcium_hardness + magnesium_hardness/2)/3.5

It is the alkalinity which is not "neutralized" by hydrogen ions released when calcium (and, to a lesser extent magnesium) reacts with malt phosphate. Distilled water has no alkalinity (well, it does actually have a wee bit but that's a technicality arising out of how it is defined and measured) so if you add even a small amount of calcium chloride or calcium sulfate these could react with malt phosphate to produce hydrogen ions which could neutralize more bicarbonate than is present. Thus, the RA is < 0.

So do my numbers look okay in my posts above? My final water profile is this: calcium level is right around 100. Chloride and sulfate both around 80. Magnesium is below 5. Sodium is below 10. RA is negative and effective hardness is 68.
 
ajdelange - that's what I assumed. But...

which could neutralize more bicarbonate than is present.
Doesn't make sense, because if the HCO3 isn't present, then it isn't going to be neutralized. So a -RA is bogus in application. It means that your mash pH is going to drop, yes (because of H+ going into solution), but negative alkalinity is not something that actually exists. That's why I asked.


Ben_Persitz - you are prolly doing everything right with the spreadsheet (but its a spreadsheet; use it as a guideline. Its not a mechanistic aqueous speciation model).

Looking at your water data, I wouldn't even dilute with distilled water. But I guess your hardness is a bit high.

Just brew it the way you want to brew it. Then post back here with your results. Your salt additions aren't going to ruin the pale ale. But we would all love to hear your results.
:mug:
 
ajdelange - that's what I assumed. But...


Doesn't make sense, because if the HCO3 isn't present, then it isn't going to be neutralized. So a -RA is bogus in application. It means that your mash pH is going to drop, yes (because of H+ going into solution), but negative alkalinity is not something that actually exists. That's why I asked.


Ben_Persitz - you are prolly doing everything right with the spreadsheet (but its a spreadsheet; use it as a guideline. Its not a mechanistic aqueous speciation model).

Looking at your water data, I wouldn't even dilute with distilled water. But I guess your hardness is a bit high.

Just brew it the way you want to brew it. Then post back here with your results. Your salt additions aren't going to ruin the pale ale. But we would all love to hear your results.
:mug:


It'll be awhile, but will do!
 
Doesn't make sense, because if the HCO3 isn't present, then it isn't going to be neutralized. So a -RA is bogus in application. It means that your mash pH is going to drop, yes (because of H+ going into solution),...

Neutralize in this context is not the same as in the usual meaning (that's why I put it in quotes) but it is similar. In the usual meaning, to neutralize means to add enough acid or base to a solution to bring it's pH to the point where the solvent is dissociated to the point where there are equal numbers of its cations and anions in solution i.e. 7 for water at 25 °C. In the context of RA "neutralize" means to add as much acid or base to a mash made with the water in question as is necessary to bring its pH to the pH of a mash with the same grist but doughed in with distilled water. If a water contains a lot of bicarbonate but little calcium or magnesium it will take acid to do this and we call the RA positive. If the water contains a lot of calcium and/or magnesium it will take base to get to the pH of a distilled water mash - not that we would want to do that but if we did, that's what we would have to do. Addition of base is the same as the subtraction of acid. Each OH- added combines with an H+ to form water or, if HCO3- is used as the base, to form H2CO3 (a small adjustment is needed for the effects of pH shift) and so we call the RA negative if the mash pH with the water in question is less than the DI water mash pH. It is perfectly valid to have water with negative RA and the best example of water that does is the water of Burton on Trent but Dortmund, Edinburgh and Vienna (according to commonly available water reports for those cities) also do. There is a chart at http://www.pbase.com/agamid/image/57446374 that plots several well known brewing cities by effective hardness vs. alkalinity. Lines of constant RA are drawn on this chart from which one can determine the RA associated with any combination of effective hardness and alkalinity.

RA is, of course, ultimately a model and a model is valid if it allows us to predict something. RA is validated because it predicts, at least approximately, the pH of a base malt mash and it does this equally well when RA is negative as it does when it is positive. If it didn't, it would not represent a valid model and we wouldn't be talking about it.

but negative alkalinity is not something that actually exists. That's why I asked.

I'm sure you meant to say that negative residual alkalinity doesn't exist but just in case you did mean alkalinity I'll point out that it is possible to have negative alkalinity for the same reason that it is possible to have negative RA. Alkalinity is defined as the amount of acid that must be added to a sample to lower its pH to some agreed upon pH. Unfortunately, there is more than one agreement out there so in brewing I use 4.3 irrespective of the water's composition. The other approach is to titrate until the number of hydrogen ions is equivalent to bicarbonate. Using 4.3 as the titration end point it should be clear that any sample with pH > 4.3 at the outset will require the addition of acid to lower the pH to 4.3. Such samples have positive alkalinity. But any sample with an initial pH < 4.3 (don't brew with such water!) would require the addition of base to raise the pH to 4.3 and such a sample would be said to have a negative alkalinity. You will never see negative alkalinity (water chemists would titrate with base to pH 7 and call the result acidity) but in terms of being able to calculate the actual sample chemistry of a carbo only system, a negative alkalinity or a positive acidity are equally informative.

Maybe another way to look at it is in terms of your bank balance which can be (but we hope is not) negative. A positive bank balance is the amount of money you can take out to bring the balance to 0. A negative balance is the amount of money you have to put in to avoid a nasty call from the bank manager. No, there are no dollars in the account when the balance is negative but you certainly had better not ignore a negative balance on this basis.
 
ajdelange - I will read your post later (too busy), but thanks for taking the time to explain. So, "RA" is a brewing "chemistry" term and not a general chemistry theory?

That's cool, it just didn't make sense for me in theory. Mathematical of course it does, but math isn't theory or reality, its a tool.
 
Yes, the term is due to Kolbach.

The paper where Kolbach introduced RA is available for download on AJ's website.
 
Can anyone answer this question? As the poster mentioned, it would be extremely helpful to those of us that aren't into the chemistry.

Is it impossible to answer appropriately or something? All we need is a baseline to work from and a list to cover most basic styles.

The IKEA reference is perfect ;)

Ok I've re-read that, still not groking it 100%, but here's a stab at another way of listing itL:

Pilsner or soft water styles: 1/2 tsp calcium chloride, 3% sauermalt
American Pale Ale: 1 tsp calcium chloride, 1 tsp gypsum, 2% sauermalt
British Pale Ale: 2 tsp calcium chloride, 1 tsp gypsum, 2% sauermalt
Hoppy/Strong British Ale: 4 tsp calcium chloride, 2 tsp gypsum, 2% sauermalt
Porter or Stout: 1 tsp calcium chloride (no sauermalt)
Cascadian Dark Ale (hoppy): 1 tsp calcium chloride, 1 tsp gypsum (no sauermalt)

Are these right? What about Hefe's, do they fall into the soft water style?

What about: Wits, Belgians, or Irish Red's where do they fall?

A listing of all the BJCP styles and the adjustments needed to RO water to get a proper baseline would really be helpful to a lot of folks. Water chemistry is (to me anyway) by far the most complex part of brewing I've had to deal with.
 
Thanks for the info!

Regarding the learning aspect... I learn much easier when I have the basics laid out... At least when I start out. It will give me and a lot of other folks a great foundation to start experimenting from.

I would personally be happy with with a short list, maybe 'ipa, light ale, porter and hefe'. I/we are not asking for a final answer on this... Just a starting point so we don't make 10 'dumpers' right of the bat. :)

It would not be impossible to provide a list of additions for each entry in the BJCP style guidelines but if someone were to do that

1. There would be conflicts because, for example, the Belgian Abbey beers are made with water ranging from very soft to very hard. Weizens are brewed all over Germany and Austria with water which is quite diverse.

2. You wouldn't learn anything if someone just laid it out for you

3. Within a given style there can be a fair amount of variation.

4. What suits your palate within a given style may not suit mine.

The guidelines were never intended to replace a cookbook nor to cover every situation. As they make quite clear they represent a starting point. You must tweak the recommendations until you are happy with the result.

If the problem is not understanding what to do with a Weizen, for example, because it is not specifically mentioned in the sticky you might try the following approach. Go to http://www.pbase.com/agamid/image/57446374 and find a city where Weizen is brewed. Munich is an obvious choice but so is Vienna and they probably brew it around Dortmund and Köln too. Identify the style that is in the sticky that is brewed in one of those cities. In this case, most are lager cities (clearly excepting Köln). Start out with the lager profile. You should also research the beer you are brewing. Though many of the AHA monographs are short on water information (in Warner's Weizen for example it isn't even mentioned). A great source is Ray Daniels "Designing Great Beers" (I think it is). And of course you can also garner information by posting questions like "I'm contemplating brewing a Weizen. How do you all treat your water for this style?" to forums like this one.
 
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