What characterizes a "single malt" whiskey?

A "single malt" whiskey is characterized by being made from malted barley at a single distillery. This means that all the malt used in the production comes from barley and that the entire whiskey is produced at one location, which contributes to its unique flavor profile. The use of a single grain type, specifically malted barley, ensures the distinctness and quality that whiskey connoisseurs appreciate.

In the production of single malt whiskey, the emphasis is on traditional methods, allowing the characteristics of the barley and the particular yeast and water used at the distillery to shine through in the final product. By being produced at a single distillery, it retains the craftsmanship and flavor integration that can vary between different distilleries. This ensures greater consistency and authenticity in the whiskey's taste.

The other characteristics mentioned in the other choices do not apply to single malt whiskey, as they specify methods or ingredients that would classify a whiskey differently, such as blending grains from various sources or using additives, which would not align with the pure and traditional ethos of single malt whiskeys.