Thick legs in bourbon suggest what about its proof?

Thick legs in bourbon, which refers to the way the liquid clings to the sides of the glass after swirling, indicate a higher proof. This visual characteristic arises because higher alcohol content creates a greater viscosity in the bourbon. When the bourbon is swirled, the alcohol doesn't evaporate as quickly, leading to the appearance of thicker legs.

In contrast, a lower proof bourbon tends to have thinner legs as it is less viscous and often evaporates more readily. Therefore, while aging may impart other qualities to the bourbon, such as flavor complexity, it does not directly correlate with the thickness of the legs in the glass. Similarly, sweetness in bourbon is influenced by various factors such as mash bill and aging process but does not directly affect the thickness of the legs either. Thus, the observation of thick legs serves as a visual cue that typically suggests a higher proof bourbon.