Bourbon is a type of whiskey that gets its name from Bourbon County, Kentucky, where it originated. Bourbon tends to be amber-colored, and a little sweeter and heavier in texture than other whiskeys.
edit How Whiskey Becomes Bourbon
By international agreement, and as stipulated in law, only the U.S. produces bourbon, while whiskey is produced in many countries.
For a whiskey to qualify as bourbon, it starts with the mash, which has to have a 51-79% corn base, with the other grains being barley and wheat or rye, depending on the distiller's preference. Unlike other liquors, there are no aging requirements for bourbon. However, to instill smoothness and improve quality, most bourbon is aged for at least four years. Bourbons aged between 2 and 4 years that have no added spirits, flavoring, or coloring are called "straight bourbons," and their aging must be clearly labeled if sold in the U.S. Exported straight bourbon only needs to indicate it is bourbon.
Oak barrels are used for the aging process, with the insides of the barrels charred to serve as a filter and coloring medium. Nearly all bourbon distillers in the U.S. use American white oak barrels because the wood is sturdy enough for aging up to 12 years, but porous enough to help filter and age the spirit to ensure quality. Bourbon is distilled at no more than 160 proof (80% alcohol by volume), and nothing can be added during the distillation process (for flavoring or coloring).
Somewhat like champagne isn't champagne unless it's made in Champagne, France, Bourbon is not actually "Bourbon" if it is made outside the USA, even though other whiskeys may adhere to the same recipe and distillation guidelines.
edit Tennessee Whiskey
The legal requirements for whiskey to be called Tennessee Whiskey are that the whiskey should be:
- distilled in Tennessee
- made from at least 51% corn
- filtered through maple charcoal, and
- aged in new, charred oak barrels.
This is the process by which Jack Daniel's is manufactured. The company is the largest whiskey producer in Tennessee and wields an outsize influence on liquor laws in the state; they lobbied the state legislature to create such stringent requirements for labeling Tennessee Whiskey. Other whiskey producers in the state, including UK-based Diageo that owns Tennessee's No. 2 whiskey distiller George Dickel, oppose these criteria and are lobbying to have them loosened.