Sunrise Arts

A copper distillery refers to a facility that uses copper equipment, particularly copper pot stills, in the process of distilling alcoholic beverages. Copper has been the traditional and preferred material for constructing pot stills for centuries due to its unique properties that contribute to the quality of the final spirit.¹

Key Aspects of Copper Distilleries:

• Copper Pot Stills: The heart of a copper distillery is the copper pot still.² These stills are typically made in various shapes and sizes and operate on a batch distillation process.³ The fermented liquid (wash or base wine) is heated in the pot, and the resulting vapors, containing alcohol and other compounds, rise through the swan neck and lyne arm to be condensed back into liquid.⁴
• Material Properties of Copper:
  • Heat Conductivity: Copper is an excellent conductor of heat, ensuring even heating of the liquid and efficient distillation.⁵ This helps prevent scorching and allows for precise temperature control.⁶
  • Malleability: Copper is easily shaped, allowing coppersmiths to create stills with optimal designs, including specific curves and bends that influence the distillation process.⁷
  • Corrosion Resistance: Copper is resistant to corrosion, especially from alcohol and acidic solutions encountered during distillation, ensuring the longevity of the equipment.
  • Antibacterial Properties: Copper can eradicate certain types of bacteria and fungi, contributing to a cleaner distillation process.⁸
• Chemical Interactions: The interaction between the alcohol vapors and the copper surfaces within the still is crucial for flavor development:
  • Removal of Sulfur Compounds: Copper reacts with and removes undesirable sulfur compounds produced during fermentation.⁹ These compounds can have unpleasant aromas and flavors (e.g., rotten eggs, rubbery notes).
  • Ester Formation: Copper acts as a catalyst in the formation of esters, which are flavor compounds that contribute fruity and floral aromas to the spirit. For example, copper promotes the reaction between acetic acid (formed during fermentation) and ethanol to create ethyl acetate, which has a fruity aroma.
• Copper Contact: The design of the still, particularly the size and height of the swan neck, the angle of the lyne arm, and whether the condenser is made of copper, influences the amount of contact the vapors have with the copper.¹⁰ Greater copper contact generally leads to a cleaner spirit with more pronounced fruity and floral notes.
• Hybrid Stills: Some modern distilleries use hybrid stills that combine a pot with a small column still.¹¹ These can be made of steel, copper, or a combination of both, offering flexibility in controlling the level of copper contact and the characteristics of the final distillate.¹²

Benefits of Using Copper in Distillation:

• Improved Flavor: Copper's ability to remove sulfur compounds and promote the formation of desirable esters leads to a smoother, cleaner, and more flavorful spirit.¹³
• Efficient Heat Transfer: The excellent heat conductivity of copper allows for better temperature control during distillation.¹⁴
• Durability: Copper stills, with proper care, can last for many years, representing a significant investment in quality spirit production