[mtnandy]

I will be brewing a traditional bock in a few weeks and am working up my water profile. I think I am finally starting to get a grasp on the relationships among the malt, pH, and the minerals. I use Bru'n water for all my water needs. Here is the recipe and profile I have worked up for my bock:

13 lbs Best Dark Munich 10L
Mash Water to grist ratio: 1.54

Ca: 39.6
Mg: 6.5
Na: 6.5
SO4: 25.7
Cl: 10
Bicarb: 120.9
Alkalinity: 100
RA: 68

How does this profile look? One question I have is on the SO4/Cl ratio. Bru'n water says that it should be below .5 for very malty beers, but I have also read that it doesn't matter at low concentrations of sulfate and chloride. Is this true? If so, what is the threshold at which the ratio becomes important? Also, Bru'n water lists Magnesium Chloride and Pickling Lime as possible water additions. I have not been able to find either of those. Where can those be obtained from and are they ever really useful?

Thanks for the help!

[a10t2]

I have also read that it doesn't matter at low concentrations of sulfate and chloride. Is this true?

I would say yes. In this case, for a malty bock, I'd shoot for 100-150 ppm Cl. That will make the ratio work out to something ridiculous, but it doesn't really matter.

Actually, I would argue that the ratio *never* matters and that what you should be doing is targeting specific SO4 and Cl concentrations.

Also, Bru'n water lists Magnesium Chloride and Pickling Lime as possible water additions. I have not been able to find either of those. Where can those be obtained from and are they ever really useful?

MgCl₂ is widely available as de-icing salt, although to find a food-safe source you might need to go through a chemical supplier (Cole-Parmer et al). Calcium chloride is more readily available and will do the same thing.

Pickling lime (aka slaked lime, canning lime, etc.) is calcium hydroxide. Any grocery store with a good selection of canning supplies should stock it. It's useful for reducing alkalinity if you have alkaline water. http://braukaiser.com/wiki/index.php?title=Alkalinity_reduction_with_slaked_lime

[mtnandy]

I would say yes. In this case, for a malty bock, I'd shoot for 100-150 ppm Cl. That will make the ratio work out to something ridiculous, but it doesn't really matter.

Actually, I would argue that the ratio *never* matters and that what you should be doing is targeting specific SO4 and Cl concentrations.

Isn't 100-150 ppm Cl too high? Bru'n water says the recommended range is 10-100.  What concentrations of SO4 should I be targeting? How well would this profile work?

52.8 Ca
6.5 Mg
26 Na
25.7 SO4
40.1 Cl
137.3 Bicarb
72 RA

[a10t2]

Isn't 100-150 ppm Cl too high? Bru'n water says the recommended range is 10-100.  What concentrations of SO4 should I be targeting? How well would this profile work?

I'm sure Martin's forgotten more about water chemistry than I'll ever know, but here's what Palmer says:

Brewing Range = 0-250 ppm.
The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds

Remember, recommendations are just that. I've never personally noticed any issues with 100-150 ppm, and that's almost always what I target for a malty beer like this. For SO4, I would avoid adding any. If you're getting 26 ppm from your water, that should be fine. The exception would be in a Maibock, where I shoot for ~100 ppm Cl and ~50 ppm SO4 to make sure the hop bitterness is more pronounced.

[mabrungard]

Unfortunately, Palmer's recommendations on chloride are flat-out wrong.  There is only one water profile from a historic brewing center that has chloride greater than 100 ppm or even near it (Dortmund).  I also have a profile for West Flanders that has high chloride, but surprise...its by the sea.  Salt water intrusion probably has an influence there.  I'm not sure if good beer is brewed in that area since the raw water is a little salty.

Keeping chloride below 100 ppm is a good idea, but you could go above that if you want a minerally note to the beer, like in a Dortmunder Export. 

The sulfate/chloride ratio (or vice versa) is mostly applicable when at least one of those ions is in the mid range of desirable chloride or sulfate concentration (in the vicinity of 50 ppm).  That way you can either have a reasonably high chloride or sulfate concentration without the clashing that occurs when both ions are over 100 ppm.  I strongly suggest that a10t2's recommendation might get some brewers into trouble.  Don't use the ratio as the only criteria.  I see that in a way he is implimenting my recommendation in that he might jack up the chloride, but keeps sulfate low.  The ratio has an influence when at least one of those ions is less than 100 ppm and that should be a more important criteria.  The other time the ratio falls flat is when either or both of the ions are at relatively low concentration.  I don't think you could taste their impact then. 

Enjoy!

[a10t2]

I strongly suggest that a10t2's recommendation might get some brewers into trouble.

Would that be when sodium concentration is also high?

The reason why I so strongly oppose the use of a Cl:SO4 ratio is that almost every day, I see a post from a home brewer who has carefully tweaked his salt additions to get the ratio just right, but has the actual concentrations at ludicrously high or low levels. I have to assume that for every brewer who bothers to ask about it, there are a dozen others who are naively calculating the ratio without knowledge of the caveats that go into using it.

[mtnandy]

The sulfate/chloride ratio (or vice versa) is mostly applicable when at least one of those ions is in the mid range of desirable chloride or sulfate concentration (in the vicinity of 50 ppm).  That way you can either have a reasonably high chloride or sulfate concentration without the clashing that occurs when both ions are over 100 ppm.  I strongly suggest that a10t2's recommendation might get some brewers into trouble.  Don't use the ratio as the only criteria.  I see that in a way he is implimenting my recommendation in that he might jack up the chloride, but keeps sulfate low.  The ratio has an influence when at least one of those ions is less than 100 ppm and that should be a more important criteria.  The other time the ratio falls flat is when either or both of the ions are at relatively low concentration.  I don't think you could taste their impact then. 

So, if I am understanding you correctly, since the sulfate is at 25.7, the ratio is somewhat important at this range. So, now I have raised the chloride level to 54 ppm, which puts the ratio at 0.5, and keeps it well below 100. I can't lower the sulfate at all because I need the epsom salt addition to get the required magnesium. How does this profile stack up?

66.3 Ca
6.5 Mg
19.5 Na
25.7 SO4
54 Cl
137.3 Bicarb
62 RA

Thanks for the help guys!

[a10t2]

That look fine. There *probably* isn't any reason to add additional Mg, and you certainly won't get any benefit from an additional 6 ppm.

http://www.scientificsocieties.org/jib/papers/1997/1997_103_5_287.pdf

[euge]

Why not add sulfate too?

[Pawtucket Patriot]

The profile you posted in reply #6 is almost exactly what I would do for a bock.  I have pretty soft brewing water; most of the time, all I try to do is get my Ca level to between 40-60 ppm with either CaCl or CaSO4, depending on whether I want to favor Cl or SO4 ions.

[mabrungard]

OOPS!

I just reread a10t2's post.  They were recommending DISREGARDING the ratio, not advocating it.  In my original read, I thought they were advocating it.  Sorry. 

As mentioned in that posting and mine, targeting chloride and sulfate levels is more important than targeting a ratio of those ions.  a10t2's comments on the shortcomings in their next post help illustrate why its not a good idea to target the ratio and lose sight of the total concentrations of either of the ions. 

For mtnandy, unless there is a flavor goal for the increased magnesium concentration, there is not a pressing need to boost that concentration.  A malt wort supplies some magnesium and I've hypothesized that a minimum Mg concentration of 5 ppm in the water is good insurance that the wort will have sufficient Mg for good yeast performance.  The 5 ppm Mg value came from another published paper that apparently used a sugar-based wort.   

The paper cited above shows a pretty high Mg concentration in the base wort used in the study, but there is not an indication of what the starting Mg concentration of the water used in the wort was.  In addition, the wort was fortified with Peptone Yeast Nutrient that happens to have a significant Mg content.  The base wort showed Mg concentration of 106 ppm.  The problem is that I can't decipher if all that Mg came from the mash and not from the nutrient or mash water. 

I keep hearing that grain and malt based wort's provide a lot of Mg to the wort, and as shown above, I still can't confirm that with definitive numbers.  That's why I currently recommend a 5 ppm Mg minimum just to be safe.  Going beyond that is a matter of desired taste.  Mg has a sour bitterness that may be desirable in some beers.  Going above the 30 ppm range might change that perception to astringent and bitter.

Sorry for the confusion and keep up the good work!

[hopfenundmalz]

Pickling lime can be found at Farm supply stores in the canning section most imes of the year.  It is seasonal in the northern states.

I find it very useful if I want to raise the pH of the mash.  It dissoles readily.

[mtnandy]

OOPS!

I just reread a10t2's post.  They were recommending DISREGARDING the ratio, not advocating it.  In my original read, I thought they were advocating it.  Sorry. 

As mentioned in that posting and mine, targeting chloride and sulfate levels is more important than targeting a ratio of those ions.  a10t2's comments on the shortcomings in their next post help illustrate why its not a good idea to target the ratio and lose sight of the total concentrations of either of the ions. 

For mtnandy, unless there is a flavor goal for the increased magnesium concentration, there is not a pressing need to boost that concentration.  A malt wort supplies some magnesium and I've hypothesized that a minimum Mg concentration of 5 ppm in the water is good insurance that the wort will have sufficient Mg for good yeast performance.  The 5 ppm Mg value came from another published paper that apparently used a sugar-based wort.   

The paper cited above shows a pretty high Mg concentration in the base wort used in the study, but there is not an indication of what the starting Mg concentration of the water used in the wort was.  In addition, the wort was fortified with Peptone Yeast Nutrient that happens to have a significant Mg content.  The base wort showed Mg concentration of 106 ppm.  The problem is that I can't decipher if all that Mg came from the mash and not from the nutrient or mash water. 

I keep hearing that grain and malt based wort's provide a lot of Mg to the wort, and as shown above, I still can't confirm that with definitive numbers.  That's why I currently recommend a 5 ppm Mg minimum just to be safe.  Going beyond that is a matter of desired taste.  Mg has a sour bitterness that may be desirable in some beers.  Going above the 30 ppm range might change that perception to astringent and bitter.

Sorry for the confusion and keep up the good work!

Wow, the rabbit hole keeps going deeper and deeper  This stuff fascinates me...
So, let me make sure I have this straight. Since bock is a malt focused style, I want a water profile that accentuates the malty sweetness in the beer. Because of this, I want to target elevated levels of Cl (below 100 ppm), while keeping the SO4 low. Since there are no definitive answers about Mg required, I will keep the concentration at 6.5 ppm with epsom salt, which sets the SO4 at 25.7 ppm. If I elevate the Cl to 54 ppm, I get a good ratio of 0.5 SO4 to Cl while keeping the Cl at moderate levels well below the taste threshold.

Hypothetically, if for some reason I could not get a good ratio AND keep the Cl below 100 ppm, it would be more important to keep the Cl levels below the threshold than to have a good ratio. Am I thinking about this correctly now?

Again, thank y'all for all the help. Up until now, I have just been plugging numbers into Bru'n water to try and match a recommended profile, and it has been working great. I am just now starting to look at the "why" of the mineral additions.

[a10t2]

I keep hearing that grain and malt based wort's provide a lot of Mg to the wort, and as shown above, I still can't confirm that with definitive numbers.

Anecdotally, I've tested worts for all of our beers with a basic home testing kit and found 380-510 ppm total hardness, 190-230 ppm Ca hardness. The base water has 50-60 ppm Ca and 2-7 ppm Mg after salt additions. So that works out to the malt contributing 16-32 ppm Ca and 37-78 ppm Mg, assuming my math is right. I'm assuming that the wide spreads are at least in part due to the wide gravity range (10.4-16.5°P), since the base malt was the same in all cases and made up at least 3/4 of each grist.

[mabrungard]

Sean,

That's better than what I've found to date.  And as mentioned above, the evidence is that about 5 ppm Mg is enough to make yeast perform better.  This implies that Mg is optional when brewing with high percentage malt worts (ie. not much simple sugars added).