Making the cuts: foreshots, heads, hearts and tails

What you're separating

A wash is mostly water and ethanol, plus small amounts of hundreds of other compounds made during fermentation - the congeners. Some are unpleasant, some carry the flavour you want, and they leave the still at different stages of the run. Nothing switches over abruptly: one fraction fades as the next grows. The four names are a practical way of dividing a continuous stream.

Before the run

Jars

Collect into clean glass jars of equal size, numbered in order. Choose a size that will give you roughly 20 to 30 jars across the run: small enough that each jar is a narrow slice of it, large enough to keep the work manageable. For a run expected to yield around five litres, 250 mL jars work well; larger runs suit larger jars.

Measuring

An alcoholmeter and a narrow trial jar let you read the strength of each jar. Note the liquid's temperature as you read, because most alcoholmeters are calibrated at 20 °C and need correcting away from it.

Notes

For every jar, record the number, the time, its ABV and the temperature at the column head. Add a word or two on smell as you go. These notes turn one good run into a recipe you can repeat.

Stripping and spirit runs

If you distil twice, the careful cutting happens in the spirit run. A stripping run is about recovering alcohol quickly, so nearly everything is collected together as low wines - although many distillers still discard a small foreshots fraction from the stripping run as well.

The jar method, step by step

1. Bring the still up gently. Heat at full power to warm the boiler, then reduce well before the first distillate appears, so the run starts at a steady trickle rather than a surge. On a reflux still, let the column settle under full reflux for a while - commonly 20 minutes to an hour - so the most volatile compounds gather at the top before you draw anything off.
2. Collect and discard the foreshots. Collect them slowly. How much to discard depends on the wash and the still: one widely used reflux-still guide suggests about 150 mL from a 25 L wash. Err on the generous side; it costs very little spirit. Keep the foreshots well apart from anything you will drink, and dispose of them safely.
3. Collect the rest of the run in numbered jars. Change jars at the same volume each time and log every one. Don't try to decide where the hearts begin while the still is running.
4. Hold the heat steady through the middle of the run. Speed is the enemy of a clean cut: more heat pushes fractions together, so the heads linger and the tails arrive early.
5. Watch for the tails, and keep collecting. The ABV begins to fall more quickly, the smell turns earthy, and the distillate may look oily or turn cloudy when diluted. Collect a few jars well into the tails; you'll decide later, and they are valuable feints.
6. End the run. Stop collecting when the jars no longer hold anything worth running again, then switch off the heat.
7. Air the jars. Cover them loosely with a paper towel or cloth and leave them overnight - 12 to 24 hours is typical - somewhere well ventilated, away from flames, sparks and heat. The most volatile notes escape, and the jars smell truer the next day.
8. Judge and blend. Dilute a small sample from each jar to drinking strength or below. Starting from the best jars in the middle, add neighbouring jars one at a time, tasting as you go, and stop when the blend gets worse. Mark which jars you kept.
9. Record the result. Note which jars made the cut, their ABV and head temperature, and the conditions of the day. That record is the starting point for the next run.

Judging each transition

Foreshots to heads

The sharp, solvent smell recedes and fruity, sweet-solvent notes take over. The spirit is still hot and harsh, but it no longer smells like a chemical.

Heads to hearts

The most important cut. The harsh edge drops away; the smell becomes clean, sweet and rounded, and the taste is smooth, with no more burn than its strength explains. Smell from a little distance rather than plunging your nose into the glass - alcohol vapour numbs the sense of smell quickly.

Hearts to tails

The sweetness fades and earthy, wet-cardboard notes appear, sometimes described as "wet dog". The mouthfeel turns oily, a diluted sample may cloud, and the ABV falls more steeply from jar to jar.

Different spirits, different stills

There is no single right cut. The same wash can be cut tightly for one spirit and generously for another.

• Neutral spirit, such as a vodka or a base for gin, is cut tightly at both ends: any character from the heads or tails counts as a fault.
• Whiskey and rum usually take wider cuts. A little of the late heads adds fruit; a little of the early tails adds body. Spirit destined for a barrel can carry more, because ageing softens it.
• Fruit brandies owe much of their aroma to the late heads, so the first cut is made with particular care.

The still matters too. A pot still separates gently, so its transitions are broad zones of judgement. A reflux still separates sharply: the hearts run at high, steady strength, and the tails arrive quickly once the column can no longer hold them back. Our guide to temperature charts explains why the thermometer behaves so differently on each.

Common mistakes

• Too much heat. A fast run smears the fractions together and narrows the hearts.
• Cutting by a number from a chart. Boiling points shift with the recipe, the still and the air pressure. See why a temperature chart can't tell you when to cut and distilling at altitude.
• Deciding in the moment. Without jars, every decision is final. With them, you can change your mind tomorrow.
• Tasting undiluted spirit. At full strength everything tastes hot, and the differences you are looking for disappear.
• Throwing away good feints - or adding foreshots to them.
• Rushing the airing. Jars judged straight off the still mislead.
• Not writing it down. The notes are what make the next run better.

What to do with the heads and tails

Heads and tails still hold a good deal of ethanol. Keep them together as feints in a sealed, clearly labelled container, stored somewhere cool and away from heat, and add them to a later spirit run with the low wines. Many distillers find that adding feints over several runs builds depth and character. The foreshots never go back in.

Sources and further reading

1. Stoica, F., Muntean, C., Giugea, N., Mărăcineanu, L. and Ionete, R. (2020). Volatile compounds in different fractions of fruits distillate obtained by traditional distillation. Scientific Bulletin, Series F: Biotechnologies, XXIV(2). PDF
2. KegLand. Making and distilling a wash (reflux still user guide). docs.kegland.com.au

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