Which characteristic helps to indicate the quality of bourbon when examined in a glass?

The characteristic that helps to indicate the quality of bourbon when examined in a glass is the legs. Legs refer to the droplets that form and run down the side of the glass after swirling the bourbon. This phenomenon occurs due to the interaction of alcohol, water, and other compounds in the bourbon. The way the legs appear can provide insight into the viscosity and richness of the liquid, which often correlates with the bourbon's aging process and overall quality.

A thicker, slower-moving set of legs may suggest a higher proof and a richer flavor profile, indicating a well-crafted bourbon. The legs can also hint at the presence of sugars and oils that develop during the distillation and aging process. These qualities contribute to the bourbon's mouthfeel and complexity, ultimately impacting the overall tasting experience.

Other characteristics like color intensity, aroma strength, and clarity can play a role in assessing bourbon but may not be as direct an indicator of quality as the observation of legs. Color can suggest age or the influence of barrels but isn't a definitive measure. Aroma strength provides important sensory information but can vary based on personal perception and glassware. Clarity, while important for appearance, does not directly relate to the quality of the bourbon in the same way that analyzing the legs does.