What factor determines the sweetness of bourbon?

The sweetness of bourbon is primarily determined by the corn content in the mash bill. Corn is the main grain used in making bourbon, and its natural sugars contribute significantly to the flavor profile of the final spirit. Higher corn content in the mash bill leads to a sweeter bourbon because corn grains have a higher sugar content compared to other grains such as rye or barley.

In bourbon production, the law requires that the mash bill must contain at least 51% corn for it to be classified as bourbon. Therefore, the proportion of corn used directly influences the level of sweetness. While other factors such as aging and proof can influence the overall flavor profile and perception of sweetness, the base sweetness stemming predominantly from the corn is foundational to bourbon's character.