Finishing Run: Fractions, Power, and Cut Tuning

A finishing run is where you earn your flavor. You collect fractions, taste what belongs in your final blend, and record cut points so you can reproduce that exact profile later.

This brandy example focuses on clean separation: remove harsh early heads, keep the fruit-forward character, and avoid pulling heavy tails too aggressively.

Quick summary

Context: from fractions to a recipe

During recipe development, you collect multiple small fractions so you can taste transitions. Once your cut points, you can switch to larger containers for heads, hearts, and tails and reproduce the same product repeatedly.

Early heads: identify and discard

Early heads are “disgusting” here, with aromas like nail polish remover and glue. The guidance is simple: they do not belong in your final product.

Smell safely

To smell a fraction, do not put your hand under the stream. Use one finger to take a small amount, place it on the back of your hand, and smell carefully. Rubbing helps drive off very volatile components so you can smell deeper layers.

Collecting fractions for tasting

The first fractions are especially important, so a practical approach is making smaller fractions early on. Keep tasting as the run moves forward and note changes in flavor.

Power setting: controlling smearing

Power setting matters because more energy in the boiler makes it easier for higher-boiling compounds to enter the vapor phase and carry over. That increases smearing.

Why brandy runs slower

For brandy here, the suggested range is about 40% power. Lower can make the run take hours; higher than about 50% creates too much smearing. The goal is to keep fruit-forward character without dragging heavy tails into the hearts.

Turn temperatures into repeatability

After you decide what fractions belong in your final blend, combine them and note the temperature range from your first included fraction to your last included fraction. Those numbers become your repeatable cut points.

Use this workflow: do the detailed fractioning once, then rerun with three larger containers (heads, hearts, tails). On automated setups, you dial the numbers in and the system can repeat the same cuts without you standing there all day.

Continue with Tasting and Recipe Development: How to Taste Fractions to build directly on this foundation.

Key Takeaways