I've used the Biabacus successfully for my past 5 AG brews, after advice from Pistol Patch to switch from a 60 to 90 min mash all AOK - if anything, I've been over shooting my OG and the yeast over attenuating, and have hit 6.4% ABV, rather than the estimated 5.3% on the past 3 brews. Zero complaints though, I just need to up my efficiency figures and have been enjoying the higher ABV
Anyhow, I started out using just one recipe, and have only changed the hops via the hop substitution area of the Biabacus to get a feel for what hops do what for the same grain bill.
I decided for the next brew to make my own recipe by moving the values from the substitution columns to the original hop bill columns. The same hop AA and weights calculated as 50 IBU's via substitutions, when entered in the original hop bill columns of a new Biabacus comes out as 58.3 IBU's (red in the screenshot). Also, the "Hops you will use" columns are populated and contain greater values in the original hop bill columns, even though not substituting (blue in the screenshot).
Pictures and source docs help at this stage:
I'm guessing it's a rounding issue maybe, although confused! I guess this means I've been brewing around 10 IBU's higher than planned (although the beer is *excellent* so no complaints there, and this fits nicely with the 6.4% abv I've been hitting).
So my questions are:
1) Is this a bug in the substitution calculations?
2) In the document "test-substituted-to-original", why are there higher suggested hops volumes than the original recipe, even though I am not substituting anything, and should ignore this column?
