Hillbilly-in-Oz wrote:...I would describe it more as the "finish" like sort of synthetic feeling left on the tongue. This was...collected at 78-82%....I didn't get to air the whole lot as much as I would have liked...and didn't want to leave this high proof gear stored open.
Therein lies some indication of your perceptions....too high proof (to be sampling) + not adequate aeration of the volatiles.
Typically, I would describe this character as “solventy” with a definite warming sensation. It is because of the keytones and higher alcohol products (with higher volatility) still in your jars. You can also sense the volatiles of a high proof sample by the “tingle” on the tongue. These would naturally reduce with proper airing, especially before attempting to make cuts, and would similarly diminish when aged in a cask.
As you know, the ethanol will have a slightly sweet taste and often does not leave the same “burn in your mouth” that the volatile constituents will. Clean ethanol will warm your chest, however, when swallowed.
Because of process variances batch to batch as well as varying viability and health of the active yeast, the amounts of the constituents will vary as well. And subtle differences in how you run the still, including water temperature variances and flow rates, will affect how and when these constituents come over to your collection jars. This can certainly have an effect on which jars you notice the “synthetic” taste in.
But you’re not lost because you can open the jars and let them properly air out (24 to 36 hours at room temperature) when you get back home. And then, go through and make proper cuts and blend. It is sometimes tough to simply “grab the middle jar” and assume it’s the center hearts. It may work...or maybe not. So, you’ll have to do a little more “homework” when you get back to it.
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