You've probably heard it before: All bourbon is whiskey, but not all whiskey is bourbon. If you're a whiskey (and especially bourbon) drinker, you need to know what that means. 

By definition, whiskey (or whisky, in Scotland) is a spirit distilled from fermented grain mash — grain varieties include wheat, rye, barley, and corn — and then aged in wooden barrels. Whiskey is made all over the world and there are many distinctive styles including Scotch whisky, Irish whiskey, and American whiskey. The most popular form of American whiskey is bourbon, which has its own specific definition. 
 
"Bourbon needs to be produced in America and made from 51 percent corn, and whiskey does not," says Maker's Mark Master Distiller Greg Davis. Bourbon also needs to be stored in new charred-oak barrels, whereas whiskey barrels do need to be oak but not new or charred. "Lastly, to be called bourbon, the liquid needs to be distilled to no more than 160 proof and entered into the barrel at 125." For other whiskies the liquid must be distilled to no more than 190 proof. David notes that this isn't just common practice — "it's actual bourbon law." 

What Makes a Bourbon: A Cheat Sheet

  • Must be made in the United States.
  • Must contain 51 percent corn.
  • Must be aged in new whiteoak charred barrels.
  • Must be distilled to no more than 160 proof and entered into the barrel at 125 proof.
  • Must be bottled at no less than 80 proof.
  • Must not contain any added flavoring, coloring or other additives.

Credit:  Men's Journal - Food & Drink, by Christoper Osburn