Barrel Charring: The Essence of Bourbon Flavor

What is Barrel Char?

Char is the blackened interior of a barrel, a result of the wood being exposed to intense heat or fire. In most cases, the inside of the barrel is literally set on fire! This charring process is a defining step in making bourbon whiskey.

The Charring Process

• Barrel Assembly: The barrel is first assembled from oak staves and held together with metal hoops. One end remains open for the charring process.
• Internal Fire: A controlled fire is lit inside the barrel. This intense fire (500+ degrees Fahrenheit) chars the inside surface.
• Char Levels: The duration of the fire determines the level of char.  This typically takes less than a minute even for the heaviest char.
  
• #1 Char - Light/Medium
• #2 Char - Medium
  
• #3 Char - Heavy
• #4 Char - Heavy, alligator char (deep, uneven char resembling alligator skin)
  
• Extinguishing the Fire: The fire is then extinguished, typically by spraying water into the barrel.
• Barrel Sealing: Once the barrel has cooled, the remaining open end is sealed, and it's ready to be filled with bourbon for aging.
  

 

Charring and the Law

 

The legal requirement for bourbon to be aged in new, charred oak containers is outlined in the Standards of Identity for Distilled Spirits (27 CFR 5.22 and 5.23). While there's no regulation specifying the char level, the use of the word "charred" implies a certain degree of charring is necessary. A very light char wouldn't meet this standard.

 

Char Levels and Flavor

 

In practice, most bourbon producers use barrels with a medium to heavy char level. This contributes significantly to the classic bourbon flavor profile. While a specific minimum char level isn't legally defined, it's understood within the industry that a certain degree of charring is essential to produce bourbon that meets the spirit's recognized standards.