A 4-year-old whiskey, having matured for over four years, has begun to take on characteristics from its cask. As it ages, the spirit naturally evaporates about 2% each year, termed the "angels' share". This maturation process softens its strong ethanol taste, allowing hints from the wood, like vanilla or toasted nuances, to emerge.
American whiskey tells a tale of innovation, tradition, and varied landscapes. Its roots go back to early settlers who distilled using native grains. A 4-year-old American whiskey would show the characteristics of its particular style, enhanced by the influence of its cask over those years.
Bourbon, a hallmark of American whiskey, maintains strict criteria. Even in a 4-year-old bottle, its signature sweetness is evident, resulting from its 51% corn mash and the specific barrels used for ageing. Tennessee whiskey, similar to bourbon, has an extra step, the Lincoln County Process, giving it added smoothness, which can be noted even in a 4-year-old spirit.
Rye whiskey, traditionally from the northeastern U.S., possesses a more robust, spicy note. A 4-year-old rye whiskey would offer a balanced blend of this spiciness and the subtleties from its cask. Corn whiskey, which usually undergoes minimal ageing, retains a pronounced grainy taste, especially evident in younger expressions like a 4-year-old bottle. In contrast, the emerging American Single Malt, while sticking to traditional malted barley methods, introduces unique American touches.
Today, after challenges like Prohibition, American whiskey is flourishing. This resurgence, with 4-year-old whiskies playing their part, is driven by craft distilleries that combine modern techniques with age-old traditions.