The Alcohol and Tobacco Tax and Trade Bureau (TTB) recently ruled to define American single malt (ASM) whiskey. The guidelines have sent ripples through the craft distilling industry.
According to the TTB, American single malt (ASM) whiskey must meet several specific requirements. The whiskey must be mashed, distilled, and aged in the United States and must be distilled entirely at one U.S. distillery. The distillation must be done to a proof of 160 or less, using a fermented mash of 100-percent malted barley.