After 17 days in the fermenter (much longer than I normally leave it), I’ve transferred my latest imperial stout into a keg.
In order to try and nail whether my ‘too much yeast in sample’ theory on preciously misses final gravity targets was correct, I took samples at start, ~25%, ~50% and ~75% of the way through the transfer for refractometer measures and an additional hydrometer sample at ~75%.
Somewhat frustratingly the refractometer result was the same for all 4 samples and around the same high level of previous brews (around 1.042 specific gravity)..
.. however the hydrometer returnes 1.022 a mere 0.006 above my final target!
One of these devices requires tuning (by a clueless me) and the other is likely accurate!
So the estimated ABV on the brewsheet is 8.9% (though the brewer’s friend calculator corrects that to 8.8%) and I have hit 8.01%!
I shall celebrate in a few weeks once it has carbonated!