Kentucky Straight Bourbon whiskey is made from a combination of grains, yeast, and water. The key ingredient in bourbon is corn, which must make up at least 51% of the mash bill. However, most bourbons have a higher corn content, typically around 70%. This high corn content gives bourbon its distinct sweetness and rich flavor.
In addition to corn, other grains are used in the mash bill to add complexity and depth of flavor. Rye is commonly used and contributes a spicy and slightly fruity note to the final product. Malted barley is also often included, which helps with the fermentation process and adds a touch of sweetness. Some bourbons may also incorporate wheat, which can lend a smoother and softer character.
The fermentation process is a crucial step in bourbon production. Once the grains are ground, they are combined with water and yeast to create a mash. The yeast converts the sugars in the mash into alcohol through the process of fermentation. This process typically takes several days to complete and produces a liquid known as the “distiller's beer.”
After fermentation, the distiller's beer is ready for distillation. It is heated in a still, which separates the alcohol from the other components of the liquid. This process allows the distiller to capture the pure alcohol, known as the “distillate,” which will become bourbon.
Once the distillate is collected, it is aged in charred oak barrels. The aging process is essential for bourbon as it imparts flavors and characteristics from the wood. The barrels are typically made from American white oak and are charred on the inside before being filled with the distillate. As the bourbon matures, it interacts with the wood, gaining flavors of vanilla, caramel, and spice.
The length of aging can vary for bourbons, but to be classified as “Straight Bourbon,” it must be aged for at least two years. Many premium bourbons are aged for much longer, sometimes even up to 10 or 20 years. During the aging process, the bourbon also undergoes evaporation, known as the “angel's share,” which contributes to its concentration and complexity.
After aging, the bourbon is typically diluted with water to achieve the desired proof before being bottled. The proof is a measure of the alcohol content and can vary depending on the brand and style of bourbon. Some bourbons are bottled at barrel strength, meaning they are not diluted and retain the full intensity of flavors.
Kentucky Straight Bourbon whiskey is made from a mash bill consisting primarily of corn, along with other grains such as rye, malted barley, and wheat. The grains are fermented with yeast and water to create a distiller's beer, which is then distilled to produce the alcohol. The bourbon is then aged in charred oak barrels, where it gains flavors and complexity, before being diluted and bottled. The result is a rich and flavorful whiskey with a distinct character that has made bourbon a beloved spirit worldwide.