Bourbon is whiskey produced primarily in Southern Kentucky – within 40 miles Louisville – where the unique, sweet tasting, hard waters are rich in limestone, keeping iron at a minimum and adding desirable minerals like magnesium and calcium.
While bourbon is made from at least 51% corn, most bourbon is composed of at least 70% corn. The other grains added, such as rye, malted barley and wheat have a profound effect on taste. For instance, rye adds a dry, spicy, peppery flavor; whole wheat will provide a soft, smooth character. Storage conditions and distilling barrels of varying levels of char also largely determine bourbon flavor and character.
The process of making bourbon starts with coarsely ground grains mixed with water which are heated to break down the starches into fermentable sugars. Cooking is sometimes under pressure with paddles agitating the mix. After cooling, it is pumped into a fermentation vat where yeast is added, along with the residue – sour mash – from a previous distillation. Sour mash prevents the growth of bacteria, giving the yeast an advantage in the process. Most bourbon is distilled twice to continue to remove impurities and strengthen the batch. Then the bourbon is barrel-aged in charred oak barrels. Oak, typically white oak, is chosen for its tight wood grain.
Bourbon is used to make some traditional favorites, such as a Manhattan, old fashioned or mint julep, but it is said that true bourbon aficionados prefer their bourbon with only a few ice cubes, a splash of water or nothing at all.