I remember seeing your original post, made a mental note to reply to it then promptly forgot. Sorry. I am always losing track of things on here anyway; things that I meant to follow and then can't find again.brale wrote:Sorry to repost this, but I'm still confused, and if anyone has any insight I would be really grateful!
The Brupaks water treatment website has the following suggestions for water profiles for different styles:
Bitter and Pale Ale. Alkalinity as CaC03 - up to 50 p.p.m. Calcium - 180 to 220 p.p.m.
Mild Ale. Alkalinity as CaC03 - 100 to 150 p.p.m. Calcium - 90 to 110 p.p.m.
Porter and Stout. Alkalinity as CaC03 - 100 to 150 p.p.m. Calcium - 100 to 120 p.p.m.
Pale Lager. Alkalinity as CaC03 - up to 30 p.p.m. Calcium - 100 to 120 p.p.m.
I just wondered why their alkalinity (carbonate) suggestions are so different to your software's suggestions. Your software suggests removing all carbonates, and then adjusting calcium, sulphate and choride for different beer styles. Brupaks seem to suggest keeping a high level of carbonates for dark ales, presumably to balance the acidity inherent in the malt.
I wondered whether you might be able to clear up my confusion! Thanks again for a great piece of software.
To your question:
I suppose it is a matter of opinion really. My view is that no beer likes carbonates; as long as mash pH is okay. I have never had a problem with mash pH being too low, but then I live in a hard water area, and there will still be a bit of residual carbonate left in my water after boiling (my preferred method).
Many of these assumptions on carbonates in water stem from Victorian analyses that were made when they first realised why some waters made better beers. It is an erroneous assumption made by many that the brewers actually brewed with this water - they didn't. It was standard practice in those days to boil all the water used in brewing; they realised that boiling the water made better beers, but probably not why; although it is too easy to underestimate our forefathers. This would have substantially reduced the carbonates.
The water compositions in the list of water areas in the calculator are those that would exist after the boil, and are closer to what the brewers would have actually brewed with. Perusal of this list is quite revealing, and does give some credence to the carbonate theory in the Brupaks stuff.
If you go to that calculator and select London Well Water, you will observe that (after the boil, remember) there is a substantial amount of carbonate left and no calcium. This is because there is insufficient calcium to bond with all the carbonate and precipitate it as chalk. Thus all the calcium has gone and there is still carbonate left. Munich is similar.
However, this causes some to say (or think) that this makes the water ideal for dark beers. That is wrong, It is obvious from this water composition, particularly the lack of calcium, that they would not have been able to brew a decent pale ale in a million years. They would not have been able to match Burton, and they would dearly have loved to give Burton a run for its money.
London specialised in dark beers because they were stuck with them - they couldn't brew anything else. They were forced to hide their inherent cloudiness behind half-a-ton of black malt. In fact their water was not ideal for anything. Strangely, the heritage of this lingers on, mainly, I think, because beer enthusiasts who write histories do not understand brewing that well, and get the wrong end of the stick.
The calculator has to assume no carbonate after boiling (as long as there is sufficient calcium) because there is no way of knowing how much is left. There will always be a little bit left.
So, the answer is, if you are having trouble maintaining a high enough pH in your mash, you may need some carbonate, otherwise you don't. Why didn't I just say that in the first place?