So, two days ago, we bottled/decanted into minikegs Donald’s Imperial Stout.
For those following along at home, it was brewed on May 31, 2004, placed into the secondary on June 8th or 9th (I can’t remember), and bottled on July 20.
The Original Gravity was 1.097. The Final Gravity is 1.030. By my calculations, that amounts to a beer with 8.8% alcohol by volume. And it ain’t done yet! The malt in the beer will continue to ferment over the next 8-12 months to yield a beer with a kick like a mule. But damn, it’s tasty!
Holycows! at that FG-OG … You’re going to end up probably adding another 2 to 3% in the conditioning, right? Ooooh.. I so much want a bottle of this 🙂
Dude..I wanna try some of this..even though I am not 21 I still wantn try!
Ok, I get different numbers 🙁
Formulas Used from:
http://www.realbeer.com/library/beerbreak/archives/beerbreak0301.php
ABW = 76.08( OG – FG )/( 1.775 – OG )
ABV = ABW( FG / .794 )
Which when I plug in the numbers gets me
ABW = 7.518
ABV = 9.752
Am I using the wrong formulas?
I would trust your numbers more – I think the ones I used were a back-of-the-envelope kind of thing:
%Wt = 105 * (OG – FG)
%Vol = 1.25 * %Wt
Doing a quick analysis in Excel (because I’m a geek), I see that the formulae I used are most accurate in the range of typical alcohol concentrations – 5-6% by volume. Your calculations are better suited for a wider range of alcohol concentrations.