What does the term "mash bill" refer to?

The term "mash bill" specifically refers to the recipe of grains used to produce bourbon or whiskey. It encompasses the specific types and proportions of grains—such as corn, rye, barley, and wheat—that are combined in the mash before fermentation. In the context of bourbon, the mash bill must contain at least 51% corn to legally be classified as bourbon.

Understanding the mash bill is crucial because it significantly influences the flavor, aroma, and character of the final spirit. Different combinations of grains lead to varying taste profiles—expressing sweetness, spiciness, or complexity—thereby allowing distillers to create unique interpretations of bourbon.

The other options address different aspects of bourbon production: aging refers to how long the spirit is left in the barrel which contributes to the flavor and color but does not define the original recipe; distillation reflects the process of converting the fermented mash into spirit but doesn’t pertain to the grain formulation; and the charred barrel treatment involves the charring of barrels to enhance flavor but is not part of the grain mix. Understanding the mash bill thus forms the foundation for knowledge about the production of bourbon.