Bourbon A whiskey made in the United States from a mash bill containing at least 51% corn, aged in new charred oak containers, distilled at no more than 160 proof, entered into the barrel at no more than 125 proof, and bottled at a minimum of 80 proof. No flavoring or coloring may be added. Straight Bourbon Bourbon that has been aged for at least two years and contains no added flavors or colors. If it is less than four years old, an age statement is required. Age Statement T