Though they do have a great deal in common, Tennessee Whiskey and Bourbon are not the same. While both must be made from a grain mash bill of at least 51% corn and then left to age in unused, charred white oak barrels, what makes Tennessee Whiskey special is the charcoal filtering process that occurs just before the new-make spirit is transferred to barrel. Known as the Lincoln County Process, this filtering strips off some of the harsher flavor notes, making Tennessee Whiskey smooth and approachable.