The difference between straight bourbon and bourbon whiskey lies in the aging process and the specific requirements that must be met for each classification. Straight bourbon is a specific type of bourbon whiskey that has been aged for a minimum of two years in new charred oak barrels. On the other hand, bourbon whiskey is a broader category that includes both straight bourbon and other types of bourbon that may not meet the aging requirements.
To understand the distinction, it is important to first understand what bourbon whiskey is. Bourbon whiskey is a type of American whiskey that is primarily made from corn and aged in charred oak barrels. It is known for its distinct flavor profile, which often includes notes of caramel, vanilla, and oak.
Now, let's delve into the specific requirements for straight bourbon. As mentioned earlier, straight bourbon must be aged for a minimum of two years in new charred oak barrels. This aging process is crucial as it allows the whiskey to develop its unique flavors and characteristics. The new charred oak barrels contribute to the rich and complex flavors of straight bourbon by imparting flavors from the wood, such as tannins and vanillin.
Additionally, straight bourbon must be made from a mash bill that consists of at least 51% corn. The remaining percentage can include other grains like malted barley, rye, or wheat. The mash bill contributes to the flavor profile of the bourbon, with different grains adding their own distinct characteristics. For example, rye can add spiciness, while wheat can impart a softer, smoother mouthfeel.
Furthermore, straight bourbon must be distilled to no more than 160 proof (80% alcohol by volume) and entered into the barrel for aging at no more than 125 proof (62.5% alcohol by volume). This ensures that the flavors and aromas of the whiskey are not overly diluted by high levels of alcohol.
It's worth noting that the aging process for straight bourbon can vary beyond the minimum two-year requirement. Many bourbons are aged for much longer periods, sometimes exceeding a decade or more. This extended aging allows the whiskey to further develop and mellow, resulting in a smoother and more complex flavor profile.
On the other hand, bourbon whiskey that does not meet the criteria for straight bourbon may still be labeled as bourbon but cannot be labeled as “straight.” These non-straight bourbons may have different aging requirements or be aged in used barrels instead of new charred oak barrels. For example, corn whiskey, which is a type of bourbon, is aged in uncharred or used oak barrels.
Straight bourbon is a specific classification within the broader category of bourbon whiskey. It must meet stringent requirements, including a minimum two-year aging period in new charred oak barrels. This aging process allows the bourbon to develop its unique flavors and characteristics. Other types of bourbon whiskey may not meet these requirements but can still be labeled as bourbon.