Chattanooga Straight Bourbon Whiskey 111 Proof 750 MLChattanooga Whiskey Cask 111 is made from a four grain mash bill which in addition to yellow corn uses three malted grains: rye malt, caramel malted barley, and honey malted barley. Chattanooga refers to this whiskey as a Tennessee High Malt, but technically this is a straight bourbon. Matured for a minimum of two years in toasted and charred barrels, Cask 111 is bottled at barrel strength without filtration at 111 proof.