Single malt whisky production is relatively new and is carried out on a small batch scale. Bourbon whiskey is the most famous of the American whiskies and contrary to believe can be made anywhere in America, it must be made from a mash containing at least 51% corn and can only be matured in new charred oak barrels for two years, it also must not be distilled at more than 80% alcohol. Tennessee whiskey is similar but can only be made in Tennessee and it undergoes one other important step; The Lincoln County Process, this is a filtration of the new spirit through sugar maple charcoal. There are several small batch single malt producers popping up now all over America.