If it weren't for distillation, spirits would not exist. Distillation is a process that separates and concentrates alcohol from the fermentation liquid. This is achieved by heating the liquid and then cooling the vapor to condense it into a high-concentration alcoholic beverage. The key to this process is that ethanol has a lower boiling point than water.
The equipment used for distillation is called a still. Over the centuries, stills have evolved from rudimentary fire-heated pots to towering industrial machines. Today, distilleries primarily use two different types of stills: the Pot Still Distillation and the Column Still. These two distillation methods are based on the same basic principles but produce spirits with significant differences in flavor and characteristics. Below is a detailed comparison of Pot Still Distillations and Column Stills.
Pot Still Distillations and Column Stills
The oldest and simplest method of spirit distillation is batch distillation, commonly known as pot distillation. This method uses a large pot-shaped still to produce spirits. Pot still distillations are usually made of copper, with a wide base that gradually narrows into a long neck.
The pot still distillation is filled with an alcoholic liquid fermented from agricultural products such as grains, sugarcane, or fruits, known as "wash," which has a lower alcohol content. The distillation process begins by heating the wash. As the liquid heats up, the resulting vapor is collected, cooled, and condensed into distillate directly extracted from the pot. The distillate can be further processed through a rectification plate to achieve a higher alcohol concentration and is typically distilled a second time to reach the desired alcohol level. Despite its lower efficiency, spirits produced by pot still distillations are highly prized for their rich flavor and aroma.
Column stills, also known as continuous stills, patent stills, or Coffey stills, originated in the early 1830s and are still widely used today.
In simple terms, column stills usually consist of at least one tall column-shaped vessel. Within the column, vertically stacked plates divide the vessel into multiple chambers. The still is heated with steam at the bottom, causing the wash to evaporate and rise through the column. The vapor begins to condense around the plates, simultaneously removing water and other undesired compounds in a process known as "reflux." Finally, the alcohol vapor reaches the top of the still and condenses into spirits.
Differences Between Spirits Produced by Pot Still Distillations and Column Stills
While the differences between continuous distillation and batch distillation may seem technical, they have a significant impact on the flavor of the finished spirit. Due to these differences, various spirit producers usually prefer one distillation method over the other. However, any spirit can be produced using either of these stills.
It is important to note that the distillation method is just one of the many variables that affect the flavor of spirits. The slow batch distillation of pot still distillations endows the resultant spirits with very rich and distinctive characteristics. Generally speaking, pot still distillations tend to produce darker, more aromatic spirits. Pot still distillations are typically used to produce flavor-rich spirits such as Tequila, certain Jamaican Rum, Mezcal, and many Malt Whiskies. Some categories, such as Single Malt Scotch Whisky and Cognac, are legally required to be produced using pot still distillations.
Spirits produced by column stills have a milder flavor and smoother taste. They are mainly used to produce Vodka, Gin, and certain types of Rum and most Bourbon Whiskey. Due to their higher efficiency, column stills are often used to produce neutral-flavored spirits, which in pot still distillations would require multiple distillations to achieve. These neutral spirits usually serve as the base ingredients for liqueurs, bitters, and other similar products.
The distillation process is a crucial variable that affects the characteristics of the finished spirits. Although both methods are based on the same principles of distillation, the technical differences between pot distillation and column distillation create uniquely flavored spirits. Understanding the distillation method of a spirit is not a perfect predictor of its flavor profile but can provide important clues for the tasting experience.
