Bourbon is whiskey made from at least 51% corn. Most bourbon is distilled from mashes that contain about 75% corn, some a little more, some a little less.
Contrary to popular belief, Bourbon can be made outside of Kentucky. However, Whiskey may not be labelled “Kentucky Straight Bourbon Whiskey” unless it is made in KY. About 98% of bourbon is made here.
Jack Daniels and George Dickel are not Bourbons. They are Tennessee Sipping Whiskies, which are made by a similar process, but are charcoal filtered. Only philistines drink whiskey made in Tennessee.
The bourbon making process begins with a “mash” of grains. As previously mentioned, mash used to make bourbon must be at least 51% corn. Different distillers use different recipes for mash. Often rye is used as the “minority” grain, which produces a grittier taste. Wheat is said to produce a sweeter, smoother whiskey.
The mash is then fermented to create the alcohol. Virtually all distillers use the “sour-mash” process which involves adding mash which has already been through the fermentation and distilling process to the new mash to be fermented. This is said to make the flavors more consistent among batches. It’s similar to using a sourdough starter.
The product of the fermentation process is a liquid called “beer”. This beer is then distilled in large stills.
The distilled liquor is then aged. The whiskey is put in handmade white oak barrels. A flamethrower is shot up into each barrel to char the inside. The char gives the bourbon its amber color. The barrels are then placed in large warehouses and kept for a varied period of time.
Lower quality whiskies are usually aged 2 to 3 years. Better whiskies are usually aged 6 or more years. However, longer isn’t always better. Distillers believe that a whiskey will peak after a certain period and will not continue to improve with further aging. Moreover, during the aging process a certain portion of the whiskey soaks into the barrel or evaporates. The longer the aging, the less bourbon left in the barrel.
Several types of bourbon are made when the barrels are tapped. Single-barrel bourbon is the contents of a single barrel (well, duh!). Distiller make “Small batch” bourbon by selected several barrels to blend and bottle. Blended bourbons are made from larger numbers of barrels blended together.
After the bourbon is blended, deionized water is added to bring it to the desired proof or alcohol content. Bourbon is usually 80 to 100 proof (i.e. 40% to 50% alcohol).