The two most common American whiskeys are bourbon and Tennessee whiskey and can be made from a variety of grains. Corn is the dominant ingredient used and must be at least 51% of the mash to be labeled a “straight whiskey.” Straight corn whiskey is the exception – it must contain at least 80% corn. Bourbon must be produced with at least 51% corn and aged in a new charred oak barrel for a minimum of two years. Other whiskey sub-styles differ and allow used oak barrels in aging. The new oak imparts a sweet, vanilla, toasted caramel flavor. Tennessee whiskey is made in the same manner as bourbon but must be filtered through sugar maple charcoal prior to aging.
Something that separates a few American whiskey varieties from European styles, is that they are aged in new charred oak barrels and remain under 80 percent alcohol by volume. Under American whiskey, there are six distinct categories with differing taste profiles; however, broadly speaking, American whiskey is sweeter, less smoky, and less peaty than Scotch and Irish whiskey. It has less of a briny or smoky flavor because it is rarely smoked with peat.
Bourbon – Whiskey must be made of 51 percent corn mash to classify as bourbon. Famously, bourbon is produced in Kentucky but is now made from coast to coast in states like New York, Indiana as well as California.
Tennessee – While similar to Bourbon in terms of grains used, Tennessee whiskey it goes through charcoal filtering to mellow the flavor during fermentation and aging.
Rye – By definition rye whiskey must be at least partially composed of rye mash and distilled to no more than 80 percent alcohol by volume.
Wheat – Wheat whiskey is made of 51 percent wheat mash.
American Single Malt – This fast-growing sector of American whiskey tends to be more smoky, aromatic and sometimes honeyed.