uberg33k
Well-Known Member
Hey all. I'm going to brew a traditional witbier soon, but I had a few problems trying to sort out the water chemistry and estimating the pH.
The grain bill is simple; 5lbs pilsen, 4 lbs flaked wheat, 1lb flaked oats. Since there's a high amount of unmalted grain in the bill, my mash schedule was going to be 20 mins @ 120F for a protein rest, ~60 mins @ 152 for conversion, and ~10 minutes at 170 for mash out. With a high percentage of pilsen, I was going to boil for 90 minutes. This recipe is all BIAB, so all water will be added at the beginning of mashing. The total amount needed to end with 5.25gal of wort at the end of boil I'm calculating out to be 8.65 gal.
My water report looks like this:
Still with me? Ok, now here are my questions:
Thank you in advance!
The grain bill is simple; 5lbs pilsen, 4 lbs flaked wheat, 1lb flaked oats. Since there's a high amount of unmalted grain in the bill, my mash schedule was going to be 20 mins @ 120F for a protein rest, ~60 mins @ 152 for conversion, and ~10 minutes at 170 for mash out. With a high percentage of pilsen, I was going to boil for 90 minutes. This recipe is all BIAB, so all water will be added at the beginning of mashing. The total amount needed to end with 5.25gal of wort at the end of boil I'm calculating out to be 8.65 gal.
My water report looks like this:
Code:
Calcium (Ca) 9.0 19.0 Bicarbonate (HCO3)
Magnesium (Mg) 1.0 0.0 Carbonate (CO3)
Sodium (Na) 6.0 9.0 Sulfate (SO4)
Potassium (K) 2.0 7.0 Chloride (Cl)
Iron (Fe) 0.0 0.9 Nitrate (NO3)
Still with me? Ok, now here are my questions:
- I'm calculating Mash Acidification with the flaked grains being classified as base malts under grain type. Is that correct?
- Will the protein rest have any effect on lowering the pH that Bru'n Water can't/isn't calculating for?
- Based on my water chemistry and mash volume, I'm estimating on adding 4 g of gypsum and 3.5 g of CaCl2. That seems to give me a decent amount of calcium and gets my SO4/Cl ratio in the same neighborhood of a Hoegaarden profile. Seem sane so far?
- If I'm doing everything correctly so far, my estimated pH is 5.6 which seems a bit too high. Granted, I know this is just an estimation and I'll need to test, but I like to be prepared. So to get me to 5.4, it looks like I'll need to add 2mL of lactic acid (88%). Sane?
- Here's where my mind starts to melt down a bit. Adding the lactic drops my RA to -68 and alkalinity to -21. As I understand it, alkalinity is the measure of resistance to pH change. I get that if it's 0, you have no buffering capacity. What does it mean when it's negative? Are those parameters out of line? What effect will negative RA and alkalinity have on the final beer?
Thank you in advance!