Racked my Marshmallow Mead v3 out of the barrel (~4.75 gallon) and did bench testing of a cacao nib tincture addition.
First thing to note is that the tincture added to the mouth feel with its viscosity. I almost started with a 10% addition...
I started at a 5% addition and quickly reduced to 2%.
The 5% wasn't really objectionable, but it destroyed the Marshmallow root flavor and that made it a problem.
The 2% was much better as the cacao dropped back so it wasn't a noticeable flavor but more of a supporting actor. I did a 1% test and this was more of what I was looking for.
A quick approximated calculation said I needed 174ml of the tincture to get to a 1% addition. I creeped up to my final by starting with 100ml. At 100ml the flavor was good but the cacao was not really present though the Marshmallow root was displaced a bit.
I added another 40 ml of the tincture which got me to ~.08% tincture added and tried again. This ended up where I decided to leave it for now. There was still the Marshmallow root flavor along with the Meadowfoam honey but the cacao was now a contributing flavor that wasn't entirely a stand out flavor on its own. I can always add more if needed, but that whole taking it out is a problem.
I added 1g K-Meta to the barrel and then racked everything back into a CO2 filled barrel and the plugged the bung up. I will revisit this in a few weeks to see how it has integrated after sitting for a bit. I'll decide after it sits if it needs any acid adjustments. Even at the ~.08% tincture addition there was a noticeable bump in the mouth feel of the drink. Sorry
@Dan O that this wasn't ready for you to try with V1 and V2.
The biggest thing that I notice missing in this version is the influence from the whiskey barrel; I assume that the first two batches have extracted all of that from the barrel. I may end doing another bench test and possibly adding a slight amount of Bourbon or other whiskey to this, though it might be less than a .5%, based on what the other tincture added.
That mouth feel bump is nice and I can't wait for my vanilla tincture to be ready for playing with.