Bourbon whiskey is an American whiskey that is a barrel-aged distilled spirit made mostly from corn. The Federal Standards of Identity for Distilled Spirits state that bourbon made for U.S. consumption must be:

• Entered into the barrel for aging at no more than 125 proof Bottled at 80 proof or more
• Distilled to no more than 160 (U.S.) proof
• Aged in new, charred oak barrels
• Made from a grain mixture that is at least 51% corn
• Produced in the United States

Bourbon has no minimum duration for its aging period. The exception is straight bourbon, which must be aged for at least 2 years. Also, any bourbon aged less than four years must state the age of the spirit on the bottle.

Bourbon that is labeled blended may contain added coloring, flavoring, and other spirits but atleast 51% of the product must be straight bourbon.