Help checking additions...

[harpo]

I am doing a black IPA this weekend. I was interested in getting some feedback on my proposed additions to my water. Initial pH (with no additions) is around 4.9, SRM is 36. 5 gallon batch. Alkalinity without additions is 25, RA is 16. With the Baking Soda additions to try and raise the pH the RA skyrockets.

Here are the stats and my initial proposed additions:

Starting Water (ppm):
Ca: 11
Mg: 2
Na: 5
Cl: 6
SO4: 15
HCO3: 31

Mash / Sparge Vol (gal): 4.3 / 4.2
RO or distilled %: 0% / 0%

Total Grain (lb): 13
Non-Roasted Spec. Grain: 2
Roasted Grain: 1
Beer Color (SRM): 35.9

Adjustments (grams) Mash / Boil Kettle:
CaSO4: 0 / 0
CaCl2: 1 / 0.976744186
MgSO4: 1 / 0.976744186
NaHCO3: 7 / 6.837209302
NaCl: 0 / 0
CaCO3: 0 / 0
Lactic Acid (ml): 0
Sauermalz (oz): 0

Mash Water / Total water (ppm):
Ca: 28 / 28
Mg: 8 / 8
Na: 123 / 123
Cl: 36 / 36
SO4: 39 / 39
Cl to SO4 Ratio: 0.92 / 0.92

Alkalinity (CaCO3): 281
RA: 257
Estimated pH (room temp): 5.13

Should I change anything? I'm using the baking soda to raise the pH. Should I consider chalk? is the Alkalinity/RA a problem?
If I do away with the baking soda and only add the Calcium Chloride and Epsom, my RA drops to +1. Is the additions below a better play?

Starting Water (ppm):
Ca: 11
Mg: 2
Na: 5
Cl: 6
SO4: 15
HCO3: 31

Mash / Sparge Vol (gal): 4.3 / 4.2
RO or distilled %: 0% / 0%

Total Grain (lb): 13
Non-Roasted Spec. Grain: 2
Roasted Grain: 1
Beer Color (SRM): 35.9

Adjustments (grams) Mash / Boil Kettle:
CaSO4: 0 / 0
CaCl2: 1 / 0.976744186
MgSO4: 1 / 0.976744186
NaHCO3: 0 / 0
NaCl: 0 / 0
CaCO3: 0 / 0
Lactic Acid (ml): 0
Sauermalz (oz): 0

Mash Water / Total water (ppm):
Ca: 28 / 28
Mg: 8 / 8
Na: 5 / 5
Cl: 36 / 36
SO4: 39 / 39
Cl to SO4 Ratio: 0.92 / 0.92

Alkalinity (CaCO3): 25
RA: 1
Estimated pH (room temp): 4.88


I am getting confused trying to remember how all this stuff plays into beers with dark SRM's, so all the help would be appreciated.

 

[ajdelange]

It is very unlikely that your mash pH will go as low as 4.9. It will more proabably be around 5.2 - 5.3 which will make a fine beer without any mineral adjustment. The only way mash pH will go too low is if the "Non-roasted specialty grains" have an inordinate titratateable acidity.

I would have no hesitation in suggesting that you just brew without any mineral additions but am always more comfortable in that recommendation if you have a pH meter available to check mash pH just in case you do have unusually acidic colored malts or if you use a whole lot of them. Should mash pH read too low (on a meter) then you simply add a little chalk to the mash to raise it.

Color has little or nothing to do with it other than that the pH check may more important for darker beers. You should, of course, check mash pH on all brews but people seem more concerned about undershoot than overshoot and if you are one of those then a pH check is the order of the day on dark beers.

 

[harpo]

So what affects a darker beer differently than a lighter beer? I seem to recall that the spreadsheets aren't as accurate with regards to predicting the mash pH for darker beers. Is that really all there is?

 

[ajdelange]

The background is that before the days that all this brewing science was understood brewers found that dark malts made better beers when the available water was alkaline. Thus alkalinity and beer color were (and still are) correlated. But we now know that there are better ways to control mash pH than just dark malt and we can use dark malt in quantities that give us the flavors we want and control alkalinity by other means. The correlation, which was never very robust (which means that color can not be used to accurately predict alkalinity nor alkalinity to predict color), is now even less so. You can brew light beer with alkaline water and dark beer with water with low alkalinity.