Kentucky Straight Bourbon Whiskey

Straight bourbon whiskey is defined as whiskey produced in any of the 50 states from at least 51% fermented maize and matured for a minimum of two years in new charred oak barrels at a proof of no higher than 160 (80% alcohol by volume [ABV]). The proof that enters the barrel cannot be higher than 125. It must be bottled at a proof of at least 80.

According to the federal Standards of Identity for Distilled Spirits in the United States, this definition is set down for the production of American whiskey.