Whiskey Production Chapter 3

Aging

• The earliest barrels were held together with rope, eventually replaced by metal hoops that were riveted together and hammered onto the bulge of the barrel.
• Charring the inside of the barrel creates a layer of charcoal, which:
  • Acts as a filtering agent, removing unwanted aromatic compounds like sulfur
  • Increases the effective surface area of the wood, allowing it to interact with the whiskey more effectively
  • Caramelizes the sugars in the wood, adding flavor and color to the whiskey
• The heat of charring also breaks down the lignin in the oak, releasing flavor compounds like vanillin, wood aldehyde, and ethyl esters.

Leaks and Leak Hunters

• Barrels are pressure-tested before use, but leaks can still develop over time
• Leaks are repaired by "leak hunters" who check the barrels regularly and repair any leaks they find

Breathing

• The uncharred part of the oak barrel allows a slow exchange of liquid and oxygen, which affects the whiskey's maturation
• This "breathing" process is responsible for the loss of whiskey, known as the "angel's share"
• The rate of evaporation varies depending on the temperature and humidity of the warehouse, with hotter and drier conditions leading to a faster loss of whiskey

Size Matters

• The size of the barrel affects the maturation process, with smaller barrels resulting in more robust flavors and faster maturation
• Larger barrels mean less evaporation and a slower maturation process
• Some distillers use smaller barrels to achieve specific flavor profiles, while others use larger barrels to reduce evaporation losses

Time is Money

• Time is a critical factor in whiskey production, as longer aging times can result in greater losses due to evaporation and increased costs
• Distillers may use various techniques to speed up the aging process, such as using smaller barrels or experimenting with different aging conditions

New Whiskey in Old Barrels

• American whiskey makers typically use new, charred oak barrels, while Scottish, Canadian, and Irish whiskey makers often use used barrels
• Used barrels can impart different flavors to the whiskey, depending on their previous contents and the type of oak used
• Some distillers use a combination of new and used barrels to achieve specific flavor profiles

Warehouse

• The warehouse environment can also affect the aging process, with factors like temperature, humidity, and light exposure influencing the final flavor of the whiskey
• Distillers may use different warehouse locations and conditions to create variety in their whiskey portfolios
• The warehouse can also be used to create consistent bottlings of familiar brands by taking parcels of mature barrels from different locations and mingling them

Casks vs. Barrels

• The terms "cask" and "barrel" are often used interchangeably, but "cask" is more commonly used in Scotland, while "barrel" is more commonly used in America
• There are some differences in the way casks and barrels are constructed and used, with casks often being used for longer aging periods and barrels being used for shorter periods

Selection and Bottling

• The selection and bottling process involves selecting parcels of barrels, dumping the whiskey, mingling the contents, and bottling the final product
• The process involves careful planning and monitoring, with distillers working to create consistent flavor profiles and achieve specific goals
• Some distillers may use techniques like chill filtering and caramel coloring to achieve specific results, while others may opt for more natural approaches.