Distillation produces one continuous stream of vapor, and the decision that matters most happens at the spirit safe: where to start collecting “hearts” and where to stop. Cut too early and you’re keeping harsh, acetone-forward heads; cut too late and you’re diluting the batch with the heavier, oily tails that carry off-flavors of their own.
We make that cut by nose and by proof reading together, not proof alone — a still running slightly differently on a humid day can shift where the transition actually happens even though the hydrometer reading looks the same as last week. It’s the one step in the whole process we’ve never been able to fully systematize, and we’ve stopped trying.
