The Basics
A copper pot still is the oldest and simplest form of distillation apparatus. It consists of a large copper vessel (the pot) in which fermented liquid is heated, a neck through which the alcohol vapour rises, a condensing system that cools the vapour back into liquid, and a collection vessel for the resulting spirit.
The principle is straightforward. Alcohol evaporates at a lower temperature than water. By heating the fermented liquid (the wash), the distiller creates a vapour that is richer in alcohol than the original liquid. When this vapour is condensed, the resulting spirit is more concentrated.
What makes copper pot still distillation different from other methods is not the principle but the level of control it gives the distiller and the role that the copper itself plays in shaping the spirit.
Why Copper?
Copper is not just a traditional choice of material. It performs an active chemical function during distillation.
Sulphur removal. During fermentation, sulphur compounds are produced as natural byproducts. In the final spirit, these compounds create unpleasant aromas and flavours, often described as cabbage-like, rubbery or eggy. Copper reacts with these sulphur compounds, binding them to the surface of the still and removing them from the vapour. This is a natural purification process that happens continuously throughout distillation.
Catalytic reactions. Copper catalyses a range of chemical reactions during distillation that convert heavier, less desirable compounds into lighter, more aromatic ones. These reactions contribute to the complexity and refinement of the final spirit.
Heat conductivity. Copper distributes heat evenly across the surface of the still, reducing the risk of localised scorching that can create burnt or harsh flavours. This is particularly important when distilling spirits from delicate raw materials like fruit juice or coconut flower nectar.
A stainless steel still would not perform any of these functions. It would simply heat and condense. Copper is an active participant in the distillation, improving the spirit at a molecular level throughout the process.
Pot Still vs Column Still
The alternative to a pot still is a column still (also called a continuous still or Coffey still). Understanding the difference between these two methods explains much of what separates craft spirits from industrial production.
Pot stills operate in batches. The distiller fills the pot, heats it, collects the spirit, cleans the still and starts again. Each batch can be monitored and adjusted individually. The distiller makes real-time decisions about when to start and stop collecting the heart cut. Pot distillation retains more of the raw material's character because it produces spirit at a lower proof, leaving more congeners (flavour compounds) in the final product.
Column stills operate continuously. Fermented liquid is fed into the top of a tall column while steam is injected from the bottom. The alcohol vapour rises through a series of plates, becoming progressively more concentrated. Column stills are highly efficient and produce spirit at very high proof, which means they strip out most of the congeners. The result is a cleaner, more neutral spirit with less character from the raw material.
Column stills are the standard in industrial spirits production because they produce more spirit per hour at lower cost. Pot stills are the standard in craft production because they produce better spirit with more character, complexity and connection to the raw material.
Multi-Stage Distillation
Many craft spirits are distilled more than once, and each distillation serves a different purpose.
Single distillation produces a relatively low-proof spirit with significant character but also potential roughness. Some spirits, particularly heavily peated Scotch whiskies, use single distillation to preserve maximum character.
Double distillation is the most common approach in craft spirits. The first distillation (the stripping run) produces a low wine. The second distillation (the spirit run) refines this into the final spirit, with the distiller making the heart cut during this second pass. Sanpatong's Rebel White Rhum Agricole and all Eau de Vie expressions are double-distilled.
Triple distillation adds a further level of refinement. In Sanpatong's production, the Rebel Red, Blue and Black expressions and all Imagin Fusion Gin expressions undergo triple distillation. For the Imagin range, the first two distillations create the coconut flower nectar brandy base, and the third distillation introduces the botanicals through maceration and vapour infusion.
Each additional distillation step increases purity while the distiller carefully manages the balance between refinement and character preservation. The goal is not to strip the spirit of all flavour (that is what industrial column distillation does) but to remove only what should not be there while keeping everything that should.
The Reflux Pipe
An important refinement in copper pot still design is the reflux system. As vapour rises through the neck of the still, some of it condenses on the copper walls and runs back down into the pot. This is reflux, and it effectively provides additional distillation within a single run.
The length, angle and cooling of the neck and reflux pipe directly affect how much reflux occurs. A taller neck with more cooling produces more reflux and a lighter, more refined spirit. A shorter, wider neck produces less reflux and a heavier, more characterful spirit.
Sanpatong's stills use ambient-cooled copper reflux pipes, which means the reflux effect is governed by the natural ambient temperature rather than forced cooling. This produces a spirit that is refined but not stripped, maintaining the character of the raw material while achieving exceptional clarity and smoothness.
The Heart Cut
The heart cut is perhaps the most important decision a pot still distiller makes.
As the spirit comes off the still, it arrives in three stages. The heads (foreshots) contain the most volatile compounds: methanol, acetone, ethyl acetate. These have sharp, solvent-like aromas and are always discarded. The heart is the middle fraction, containing the purest and most desirable spirit. The tails (feints) arrive last, containing heavier compounds: fusel oils, fatty acids, and other compounds that contribute harshness and off-flavours.
The distiller's job is to identify precisely when the heads end and the heart begins, and when the heart ends and the tails begin. This is done through sensory evaluation: tasting, smelling and assessing the spirit as it flows from the still. There is no automated system that can replicate the judgment of an experienced distiller.
A tighter heart cut produces a purer spirit but at a lower yield. A wider cut produces more spirit but introduces more of the heads and tails character. Craft distillers typically take a tight cut and accept the lower yield. Industrial producers take a wider cut and then deal with the impurities through filtration and additives.
Why It Matters in the Glass
The method of distillation is not an abstract production detail. It directly affects what you taste.
A spirit distilled in a copper pot still, with a careful heart cut and no post-distillation chemical treatment, carries the character of its raw material into the glass. You can taste the cassava in Elevated Vodka, the sugarcane in Rebel White, the coconut flower nectar in Imagin. The connection between ingredient and spirit is preserved because nothing in the process has stripped it away.
A spirit produced in a column still, carbon-filtered and smoothed with glycerin, tastes of the process, not the ingredient. The character has been manufactured, not distilled.
Copper pot still distillation takes more time, costs more money and produces less volume. It also produces better spirits. That is the trade-off, and it is the one that defines craft distillation.
Sanpatong Distillery uses multi-stage alembic copper pot stills with ambient-cooled copper reflux pipes across its entire production. Every spirit is produced without activated carbon purification.
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