Water questions for an imperial stout

[eval]

I'm brewing a 20 liter (5.28 gallon) batch of russian imperial stout (67.7 SRM) with quite a lot of roasted malts.

Grain bill:

7,50 kg Pale Malt (Weyermann) (6,5 EBC) Grain 1 80,6 %
0,68 kg Amber Malt (100,0 EBC) Grain 2 7,3 % (Roasted malt)
0,56 kg Roasted Barley (Thomas Fawcett) (1199,7 EBC) Grain 3 6,0 % (Roasted malt)
0,34 kg Carafa Special I (Weyermann) (900,0 EBC) Grain 4 3,7 % (Roasted malt)
0,23 kg Caramunich III (Weyermann) (139,9 EBC) Grain 5 2,5 %


Would something close to the "Black Balanced" water profile from Bru'n water be a good target?

"Black Balanced" profile:

Calcium 60
Magnesium 10
Sodium 20
Sulfate 47
Chloride 38
Bicarbonate 160

(RA 84)
(SO4/Cl ratio 1.2)


My starting water is:

Calcium 18
Magnesium 1.5
Sodium 1.8
Sulfate 17
Chloride 1.5
Bicarbonate 45


I batch sparge and will target two equal runoff volumes. To do that I would need to mash with 22.5 liter and sparge with 13.8 liter.


I only have CaCO3 (Chalk) and NaHCO3 (Baking Soda) available for adding alkalinity and have been fiddling around with the Bru'n water spreadsheet to figure out my water additions. This is what I came up with:

Mash water (22.5 liter):
0.9g Gypsum
0.5g Epsom Salt
1.6g Baking Soda
1.8g Calcium Chloride
1.1g Chalk

Sparge water (13.8 liter):
0.6g Gypsum
0.3g Epsom Salt
1.1g Calcium Chloride


This would give me a finished water profile:

Calcium 69.1
Magnesium 3.5 (I know its lower than the target)
Sodium 21
Sulfate 47.1
Chloride 40.1
Bicarbonate 156.9

(RA 78)
(SO4/Cl ratio 1.2)


According to Bru'n Waters estimation this would give me a room temp mash pH of 5.4.

Does this final water seem reasonable for an imperial stout?

Would it make sense to skip the CaCl2, MgSO4 and CaSO4 in the mash and add all those to the boil instead since they all will lower pH and I guess that is something I do not need with all the roasted malt that will be in the mash. I would of course need to compensate by lowering the additions that add alkalinity to the mash water.

Would you acidify the sparge water (given my water and proposed additions) even though I batch sparge and have all those roasted malts in the mash?

 

[thegreatmaibockaddict]

Yeah, I think you are over thinking things on this.

I had water issues that I needed to solve at one time, as too many solids (chlorides and the like) were present in my water. Thing is, it had no effect whatsoever on the really big brews like Imperial Stout and Barleywine.

i would not make yourself too crazy over water unless you have a chlorine issue of some sort when making big beers. You will not notice!

 

[mchrispen]

First, my compliments on a thoroughly laid out post. That data is very helpful.

Rather than comment on your target profile - which is entirely your preference, I would suggest losing the Chalk addition entirely. I am betting you can raise the alkalinity level with just baking soda such that you will not go below 5.4... and not add an extraordinary amount of sodium - and I think it might complement your stout. Chalk doesn't dissolve as well - and the reaction occurs more slowly than desired. Again - as for the rest of the ion concentrations - they match to the black balanced profile in Bru'n. Personally, I would slightly lower the gypsum addition and go ahead and get the magnesium level to 10 from a tiny more epsom. You should still have adequate calcium to remain near 50 ppm. Concentrate on the mash pH first...

Another option might be to steep a portion (or all) of the roasts separately (such as the Carafa Special and Roast Barley) and return them to the mash during sparge. Gordon Strong talks about that technique in Brewing Better Beer. A cold steep might keep some of the more bitter and astringent flavors from the roasts coming through - with a "smoother" roast character. I personally like the cold steep option and use it in my porters and stouts. It should be noted that the pH drop from the roasts will occur in the boil kettle - which may or may not be a concern. You can zero out those values in Bru'n Water to see the impact - or on the paid version - there is a check box to take them out of the mash pH equation (separate steep) and prediction.

Would it make sense to skip the CaCl2, MgSO4 and CaSO4 in the mash and add all those to the boil instead since they all will lower pH and I guess that is something I do not need with all the roasted malt that will be in the mash. I would of course need to compensate by lowering the additions that add alkalinity to the mash water.

That is a possibility, but you maybe missing the calcium required for a complete reaction driving the right pH in the mash. The added calcium from those minerals is beneficial to the acidification and conversion processes in the mash. Then again - light lagers are made with very little calcium - so I could be wrong.

Would you acidify the sparge water (given my water and proposed additions) even though I batch sparge and have all those roasted malts in the mash?

You don't give your starting water alkalinity - but with such a low bicarb level - I would guess you will be fine without. Acidifying the sparge water will help ensure you don't extract tannins however. Maybe only take it down to 6.0 pH. Should be a very little amount of acid.

Does this final water seem reasonable for an imperial stout?

Depends on your goals. I have had extremely dry and bitter RIS and rich and malty RIS, and some in between. I tend to like the fuller more velvety stouts - and would err more toward the malty side. But consider that the gas (nitro v co2) plays a role there as well. Others may have differing opinions than I. Brew it - and make some changes next time to your preference.

 

[eval]

First, my compliments on a thoroughly laid out post. That data is very helpful.

Thanks and sorry for replying and thanking you for your very helpful post this late!

Rather than comment on your target profile - which is entirely your preference, I would suggest losing the Chalk addition entirely. I am betting you can raise the alkalinity level with just baking soda such that you will not go below 5.4... and not add an extraordinary amount of sodium - and I think it might complement your stout. Chalk doesn't dissolve as well - and the reaction occurs more slowly than desired. Again - as for the rest of the ion concentrations - they match to the black balanced profile in Bru'n. Personally, I would slightly lower the gypsum addition and go ahead and get the magnesium level to 10 from a tiny more epsom. You should still have adequate calcium to remain near 50 ppm. Concentrate on the mash pH first...

I understand that after getting the mash pH in the correct range the rest is just flavoring and personal preference. I have tried changing my additions according to your suggestions and I will end up with about 44 ppm sodium if I ditch the chalk and increase the baking soda addition. I guess that would be fine?

What mash pH would you target on an imperial stout? Would 5.4 be a good target?

I have a pH meter that I recently bought and have never used yet. What would be a good way of doing the baking soda additions? Should I add around half of what Bru'n suggests to the mash and then wait for 10 minutes and take a pH reading before I add more if it is needed? Or should I trust the estimation from Bru'n and add it all and then make corrections later if I notice that I have a too high or too low pH?

Another option might be to steep a portion (or all) of the roasts separately (such as the Carafa Special and Roast Barley) and return them to the mash during sparge. Gordon Strong talks about that technique in Brewing Better Beer. A cold steep might keep some of the more bitter and astringent flavors from the roasts coming through - with a "smoother" roast character. I personally like the cold steep option and use it in my porters and stouts. It should be noted that the pH drop from the roasts will occur in the boil kettle - which may or may not be a concern. You can zero out those values in Bru'n Water to see the impact - or on the paid version - there is a check box to take them out of the mash pH equation (separate steep) and prediction.

Thanks for the suggestion. I will do some more reading and maybe try cold steeping the next time I brew a stout. I'm a fairly new brewer and this is my first stout. I think I will try the traditional way the first time

You don't give your starting water alkalinity - but with such a low bicarb level - I would guess you will be fine without. Acidifying the sparge water will help ensure you don't extract tannins however. Maybe only take it down to 6.0 pH. Should be a very little amount of acid.

My starting alkalinity is 37 ppm. Yes, according to Brun water I will only need about 0.6 mL of 88% lactic acid to get the pH of my sparge water down to 6. I guess I will do that...

Depends on your goals. I have had extremely dry and bitter RIS and rich and malty RIS, and some in between. I tend to like the fuller more velvety stouts - and would err more toward the malty side. But consider that the gas (nitro v co2) plays a role there as well. Others may have differing opinions than I. Brew it - and make some changes next time to your preference.

I tend to like the smooth and malty stouts more as well.

Once again, thank you!

 

[mabrungard]

Since this has some bearing on big beers, I'll add this to the discussion. I recently bought the book: Amber, Gold, and Black which is a British book on many historic beer styles in the UK. In it, there is a chapter on Burton Ale. That is not the beer many might think. Its not an IPA or PA. It was a rich malty beer that was stored and aged. Kind of a Christmas Ale if I recall correctly. It was also related to Russian Imperial Stout.

Anyhow, since these malty beers were brewed in Burton, they did have the high sulfate content typical of their water. So it's apparent that you can successfully brew a big beer with high sulfate. I would not have expected that, but it does make sense since sulfate helps dry the finish in a beer. A big malty beer can use some dryness to help the balance.

Beer for thought!

 

[mchrispen]

...and I will end up with about 44 ppm sodium if I ditch the chalk and increase the baking soda addition. I guess that would be fine?

That is on the edge of my flavor threshold, but with so much going on in a stout - I would consider it acceptable.

What mash pH would you target on an imperial stout? Would 5.4 be a good target?

5.4 works well, but many mash darker beers in a higher pH range. Perhaps 5.5 or so.

I have a pH meter that I recently bought and have never used yet. What would be a good way of doing the baking soda additions? Should I add around half of what Bru'n suggests to the mash and then wait for 10 minutes and take a pH reading before I add more if it is needed? Or should I trust the estimation from Bru'n and add it all and then make corrections later if I notice that I have a too high or too low pH?

This is a bit of a conundrum. Since you indicated that you would mash the roasts and crystals, then I would add the baking soda with the other minerals in the strike water, and make sure it is fully dissolved before you mash in. This seems a bit backwards, and you will be flying blind a bit. I would not then take a mash pH reading for a few minutes... you need to thoroughly distribute the water, minerals and grist - so stir very well. Then let this sit for about 10 minutes and then take the pH reading. You should be able to adjust pH downward if necessary with a small acid addition. I am guessing you will be fine - and do not panic if you are at 5.4 rather than 5.5. Make good notes of your additions and the pH readings - and you can adjust for the next brew.

My starting alkalinity is 37 ppm. Yes, according to Brun water I will only need about 0.6 mL of 88% lactic acid to get the pH of my sparge water down to 6. I guess I will do that...

I would only because I cannot stand astringency in stouts or porters... but that is such little alkalinity - use the acid only for insurance.

I think your profile will help in the malty side - or you can look at the black malty profile on Bru'n... I don't think you are that far off.

Best of luck on brew day!

Martin - any ideas on recipes from that? Sounds compatible with some of the discussions from Mitch Steele's IPA book...

 

[eval]

Thanks Matt and Martin.

Just wanted to let you know that I brewed my recipe this Saturday. As Matt suggested I changed the water profile to "Black Malty" instead of "Black Balanced".

As a a last minut change I ended up subbing a tiny bit of baking soda with chalk instead just to get the sodium down to ~33 ppm. The chalk addition for my 22.5 liters of mash water was only 0.9g. Anyway... Don't know how it affected the pH, but I ended up with a stable reading of 5.44 when I got a sample after ~15-20 minutes of mashing and let it cool to 24C. Hats off Martin, Brunwater estimated a mash pH of 5.4!

I'm still working on tweaking my Beersmith equipment profile and I ended up hitting the pre-boil gravity on the point, but then the post-boil was 7 points lower than expected (boil off issue). I hope it will still make a decent imperial with an OG of 1.091. Did a 1oz FWH addition of Warrior (~50 IBU) and a 1.7oz 15 min addition of Challanger (~18 IBU). I prefer stouts with less bitterness.

Pitched my decanted 3.2 liter stirplate starter with Wyeast 1028 (London Ale) and it has been fermenting at 65F until today when I bumped it up to 66.5F. I will continue to increase the temperature towards the end of the week.

I will let you know how it turns out in a couple of months

Once again, thanks for all feedback and help!