how much acid are you typically adding to the mash?

[ajdelange]

... it's the San Francisco water profile from BeerTools Pro.

Ca - 36
Mg - 25
Na - 17
HCO3 - 80
SO4 - 20
Cl - 26

As is so often the case with published profiles, this one cannot exist. It has twice as much charge from positively charged ions as negatively charged ones. The two must balance. This profile cannot be synthesized by nature or me. I suspect that the calcium and magnesium numbers may be hardnesses, not ion content and that may explain why the balance is so far off.

The following profile, taken from the SFPUC 2009 water report represents the average values from the report, balances and can be synthesized.


Ca - 12 mg/L (as the ion)
Mg - 4.5 mg/L (as the ion)
Alkalinity - 50 ppm as CaCO3 corresponding to 58.4 mg/L bicarbonate
Sulfate - 17 mg/L
Cl - 9.5 mg/L
Na - 14 mg/L

To put together 9 gallons of water with this profile starting with deionized water you would need to add:
0.033 g CaCl2.2H2O
0.506 g NaCl
1.520 g MgSO4.7H2O
1.001 g CaCO3
1.021 g NaHCO3
0.779 g CO2

The procedure is to suspend all the salts in the full volume of water and then bubble CO2 through it while stirring until all the CaCO3 is dissolved and the pH is close to 7. This is how nature got the bicarbonate in the San Francisco water and you must do the same. If you are willing to go to this trouble you can realize the given profile with a maxium error of 2.3% which is pretty darn tight. However, doing the CO2 sparging thing is a big pain and not really worth it. You are going to that trouble in order to get the alkalinity close to the profile's alkalinity and as you are going to add acid to set mash pH with HCl a waste of time. Nearly all the bicarbonate (the chalk and CO2) you put in will be converted to CO2 gas again and escape. The consequences of skipping the carbonate and bicarbonate would be less acid required to establish mash pH and lower sodium and calcium. These can easily be made up for by adding more CaCl2 and NaCl.

Adding 1.19 grams of calcium chloride, 0.73 grams deiodized table salt, 0.33 grams gypsum and 1.1 grams of epsom salts would get you

Ca - 11.8 mg/L
Mg - 3.2 mg/L
SO4 - 17.9 mg/L
Na - 0.5 mg/L
Cl- 29.9 mg/L

which I would think would be a reasonable profile with which to brew. Note that calcium, magnesium and sulfate are about right but that sodium is low and chloride high. You would wind up with high chloride as a consequence of neutralizing bicarbonate with hydrochloric acid and so that seems acceptable. If you want more sodium for taste then simply add more sodium chloride. Extra chloride won't hurt at these levels but sodium really doesn't do much unless you want the beer to taste a bit salty.

[beltbuckle]

As is so often the case with published profiles, this one cannot exist. It has twice as much charge from positively charged ions as negatively charged ones.

Well damnit - who the heck is making up these profiles? Does some cruel person dream them up to give homebrewers pain? I jest because in BeerTools it has this water profile, and in the comments it says something like "used for brewing steam beer" so of course I thought this must be the perfect one for a cal common...

Adding 1.19 grams of calcium chloride, 0.73 grams deiodized table salt, 0.33 grams gypsum and 1.1 grams of epsom salts would get you

Ca - 11.8 mg/L
Mg - 3.2 mg/L
SO4 - 17.9 mg/L
Na - 0.5 mg/L
Cl- 29.9 mg/L

which I would think would be a reasonable profile with which to brew. Note that calcium, magnesium and sulfate are about right but that sodium is low and chloride high. You would wind up with high chloride as a consequence of neutralizing bicarbonate with hydrochloric acid and so that seems acceptable. If you want more sodium for taste then simply add more sodium chloride. Extra chloride won't hurt at these levels but sodium really doesn't do much unless you want the beer to taste a bit salty.

That looks good but do would you bump up the CaSO4 to get more calcium? Correct me if I am wrong but from Brew Strong I thought we wanted a minimum of 50ppm calcium for yeast health?

[ajdelange]

Well damnit - who the heck is making up these profiles? Does some cruel person dream them up to give homebrewers pain?

I wish I knew because I'd love to understand how they come up with these. Many of them are copied from somewhere else without a thought as to whether they are reasonable or not. They commonly, as does this one, list bicarbonate ion concentration which is meaningless unless they give pH as well which they never do. Furthermore, there is confusion about units. Are the calcium and magnesium numbers mg/L or ppm as CaCO3? (note: if I treat them as ppm as CaCO3 the imbalance is not so great and the values do fall within the range measured by SFPUC so that's probably what they are but I'm still just guessing).

That looks good but do would you bump up the CaSO4 to get more calcium? Correct me if I am wrong but from Brew Strong I thought we wanted a minimum of 50ppm calcium for yeast health?

That's up to you and it depends on your goals. There is, of course, another piece of information you don't have and that is what Anchor does with the water once it is in plant. They might dose it up with gypsum thus increasing the calcium content over what is in the area water or they might not. There is no doubt that calcium does lots of good things for beer but it is also plain that a fair number of the worlds classic beers are brewed with soft water.

I think the simplest thing to do here is just add 5 grams of calcium chloride to the 9 gal of RO water and brew the beer. This will give you 40 mg/L Ca++ and 70 mg/L Cl-. In a subsequent brew you might want to add about 1.7 grams gypsum which would give you sulfate at about 28 mg/L and, with the calcium chloride, calcium at just over 50 mg/L. See if you like what the sulfate does. If you do, stay with it or add a bit more to see if more is better.