Help with my first all-grain imperial stout

So, I want to brew an all-grain RIS. It's a re-tooling of the very first beer I made, a partial-mash RIS. The partial mashing was easy, as the specialty grains only required steeping, and the extract is already converted. Just add to sufficiently hot water, boil, and BOOM! RIS. It was great!

I've made all-grain beers before, but never darker than, say, 12 SRM (an ESB). When I made those, the water adjustments were quite easy, and it was trivial to stay within recommended brewing ranges.

Well, the RIS recipe I came up with is hovering around 50 SRM. Needless to say, the alkalinity needed to mash that is quite high.

So, to get to point, I'm wondering what the best way to go about doing the RIS mash would be.

As I play around with water calculators, it looks like I need to add ridiculous amounts of chalk and baking soda, and that's driving up my other mineral contents past their recommended levels.

I'm thinking of mashing the base grains separately, and tweaking salts to nail my chloride:sulfate ratio. Then, I want to steep the specialty grains separately, then combine the two worts into the tun and lauter/sparge from there.

Will that work? I can't think of a reason why it wouldn't.

That should work, but you're probably over-thinking it. While I'm certainly no water expert, I have played around with it a bit. That said, last summer I made a RIS that was pushing 70 SRM and all I did was add a bit of calcium chloride. It turned out fantastic.

When I did my big ol' bourbon stout I just threw all the grains in and mashed at 159. Tastes pretty damn good to me without any water additions. Went from 1.103 to 1.018 too.

Just brew it, once you're happy with the recipe then start doing water adjustments.

I forget the SRM, but it fairly resembles the nasty oil that comes out of my old Benz, so whatever the SRM is of used and abused motor oil is.

I would add the planned amount of baking soda, based on the flavor you want. Then if your mash is still acidic you can add some CaC03. Here's my experience with CaCO3 -- you can't really add too much, because no matter how much you put in it will only raise the pH a little, but it will raise it enough to put it in a good range. Beyond 2 grams/gallon will do almost nothing. And the high levels of calcium won't hurt anything, and any excess just settles out. But I check the pH before adding it to see if I need it. The water calculation spreadsheets don't apply so well at this extreme.

If you pre-dissolve your CaCO3 in CO2 most of what I said above does not apply.

HotbreakHotel said:

If you pre-dissolve your CaCO3 in CO2 most of what I said above does not apply.

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What?

beerkrump said:

What?

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You can either put CaCO3 in the mash directly or dissolve it first in carbonated water. As I understand dissolving it first makes it more effective at raising pH. I don't know anything more about it because I've never done it, and I doubt if I ever will. I just wanted to clarify...not confuse

OK, this has made me feel a little better about adding all that chalk and baking soda. My primary concern was just that I would overload it with too many other minerals. I estimate that I'll need 15 grams of chalk and 10 grams of baking soda for the whole mash, so that's really not too bad at all.

And I always test my mash pH. pH strips are wicked cheap. I'm contemplating getting my hands on a used pH meter, though, as they're far more reliable.

HotbreakHotel said:

You can either put CaCO3 in the mash directly or dissolve it first in carbonated water.

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That's a lot different than CO2.

CaCO3 is relatively insoluble in water. As the acidity is increased , the solubility increases and CO2, water, and calcium salts are created and the pH goes up (acidity down).

eq 1. CaCO3(s) + 2 HCl(aq) <-> CaCl2(aq) + CO2(g) + H2O(l)

In carbonated water, CaCO3 reacts with CO2 and H2O to form the highly soluble Ca(HCO3)2, which only exists as a solute.

eq 2. CaCO3 + CO2 + H2O <-> Ca(HCO3)2

This increases the amount of Ca in solution, making the likelihood of the first reaction (eq 1.) happening greater.

That's a lot different than CO2.

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Way to go with the chemistry stuff!! :rockin:

Thanks for clarifying. I know water chemistry like I know electricity -- do this and that happens, but I don't always know why... so thanks for clarifying!