Pot still or column still: protecting pear aroma
Braken Hill Distillery holds 3,000 L of pear wash at 8% ABV and 3,000 L of wheat wash at 10% ABV. The plant is a 1,000 L copper pot still with a short, wide neck, plus a column still with 20 plates. The pear spirit is meant to be bottled as a varietal eau-de-vie with pronounced fresh-pear aroma; the wheat spirit is destined for a neutral vodka. Fermentation of the pear was warm at 28 °C and finished in four days. The still operator proposes running the pear wash through the column still because it is faster and delivers higher strength in a single pass. Running the pear on the pot still will need three separate charges and a second distillation of the low wines.
1. Which still should the pear wash go through, and what is the reasoning?
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Pot still. The pear character is not created in the still - it is carried there by fermentation-derived esters and other congeners, and the still's job is to not throw them away.
- A 20-plate column runs with high reflux. Each plate re-condenses and re-vaporises the vapour, so ethanol is purified away from the heavier and lighter congeners. The output is strong and clean - which is exactly what you want for vodka, and exactly what destroys an eau-de-vie.
- The pot still's short, wide neck gives little reflux, so congeners pass over into the low wines and then into the spirit.
Speed and single-pass strength are real advantages, but they are not the objective here. Note the compounding factor: a warm, four-day ferment has already limited the fruity esters available, so distillation is the last chance to protect them, not a place to strip them out.
2. The operator runs the pear wash through the column anyway. Describe the spirit that results and say what you would do differently with the two washes.
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The result is a high-strength, neutral, clean spirit with little or no recognisable pear. It would be technically sound - good yield, high % ABV off the still - and commercially wrong: nothing distinguishes it from a grain-neutral base, so it cannot carry a varietal eau-de-vie price.
Reallocation:
- Wheat wash → column still. Neutrality is the goal, and the column delivers it efficiently.
- Pear wash → pot still, first distillation to low wines (roughly 25–30% ABV), then a second run for the spirit.
This is a judgement about matching process to intent, not about which still is 'better'. The same plant can serve both products if each wash is routed to the still that suits its target style.
3. Where should the operator make the cuts on the pot still run, and what specifically should they be alert for with a pear wash?
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Cut on nose and taste, supported by strength, not on strength alone.
- Heads (first runnings): sharp, solvent, nail-varnish, stinging. Discard. These carry acetaldehyde and ethyl acetate.
- Hearts: clean pear, the reason the run exists. Keep.
- Tails: wet cardboard, vegetable, cloudy when diluted. A small tail inclusion can add texture and weight to an eau-de-vie, but too much muddies the fruit.
Pear-specific point: pear is pectin-rich, and pectin breakdown during fermentation releases methanol, which concentrates in the early runnings. A warm ferment increases this risk. So the heads cut for a pear wash should be judged more cautiously than for a grain wash - smell and taste the fractions rather than assuming a fixed volume or a fixed temperature. The operator should also expect methanol to show up in the first fraction regardless of how clean the ferment looked.