Bru'n Water and long boils

[BamaPhil]

So I've just gotten into water chemistry in the last few batches. I've been using RO water built up with gypsum, calcium chloride, and (if necessary) baking soda to hit the proper ion concentrations and pH.

Here's where I'm a bit confused, I'm about to do a Barleywine where I'll be doing a long boil to get down to my target OG. Because of the grain bill and longer (2 hour) boil I'll be using roughly twice the water for mashing and sparging than I'm used to.

Because of the higher water volume, it calls for me to use a corresponding higher amount of salts to get the right ion concentrations. Makes sense to me, but since I'm boiling down from 11.5 gallons pre-boil to 6 or so post boil, will that not drive my concentrations too high?

The spreadsheet shows them in the proper range, just want to make sure I'm not missing something. Does it use post-boil volume to approximate the concentration? I'm sure some of the ions get left behind in the grain with the water. I'm probably splitting hairs here, I'm mostly just trying to make sure I understand the way the spreadsheet works.

Thanks!

 

[eluterio]

never thought of this good question.

 

[mabrungard]

Concentration is a fact of the boil. However, a typical boil is only loosing 10 to 15 percent of the original volume. If a particular boil will be longer or more vigorous, then it is possible that you could overconcentrate the water's ionic content and create minerally tasting beer.

Under that condition, it would be best to plan the mineral additions based on the post-boil volume.

 

[xpops]

Concentration is a fact of the boil. However, a typical boil is only loosing 10 to 15 percent of the original volume. If a particular boil will be longer or more vigorous, then it is possible that you could overconcentrate the water's ionic content and create minerally tasting beer.

Under that condition, it would be best to plan the mineral additions based on the post-boil volume.

Do the mineral addition calculations already take into acount that 10-15% concentration, or should we in fact always be planning our additions based on post-boil volume?

 

[BamaPhil]

Concentration is a fact of the boil. However, a typical boil is only loosing 10 to 15 percent of the original volume. If a particular boil will be longer or more vigorous, then it is possible that you could overconcentrate the water's ionic content and create minerally tasting beer.

Under that condition, it would be best to plan the mineral additions based on the post-boil volume.

Wow a reply from the Man himself! Thanks for jumping in. I had been reading a lot about water but nothing was really sticking until I got into Bru'n water. It's definitely improved my brewing water knowledge.

So let's say I back off on the mineral additions to keep the sulfate and chloride in check, but then of course my calcium goes down as well. Wouldn't that result in a higher residual alkalinity that may potentially leave my mash pH too high?

If so, would the solution be to just use acid to bring the pH back down to acceptable levels?