Ninety-nine percent of America’s iconic whiskey (Congress declared bourbon the national spirit in 1964) is produced in a 900-square-mile area of Kentucky bluegrass country. The real thing is distilled from a mash of corn, barley, and rye, and must contain at least 51 percent corn. Aging in charred new oak barrels gives the spirit its hint of sweet vanilla.
Unlike Scotch, bourbon is never blended. At the same time, a very limited number of bourbons that are biding time in a distillery’s barrels may be combined to yield bottlings of special character—so called small batch bourbons, the “class act” of the bunch in the minds of most bourbon connoisseurs.