What Are Legs In Wine And Do They Affect The Quality?

When we watch a connoisseur going through the complicated assessment of a glass of wine, we see a whole ritual that involves sniffing and sipping. They might let the wine breath and, once it is poured, will likely swirl it. What's up with the last of these? Swirling is how you determine the wine's "legs," which are the streaks that stick to the side of the glass. So, what do these legs tell us about the quality of the wine? To be honest, not a whole lot. As Vince Vidrine, head winemaker at Cowhorn Vineyard & Garden, told The Takeout in an interview, "I don't know anyone who uses legs as a quality assessment tool."

Vidrine explained that how "leggy" a wine is may be related to the amount of ethyl alcohol and glycerol it contains. He also noted that both of these have a slightly sweet taste to them. However, he went on to say, "Because wine is so compositionally complicated, it wouldn't really tell you if a wine is sweet or mouth-filling as a whole." Nor do the legs tell you much else about the wine that can't be determined through other observational methods, which is why, while sommeliers may still swirl, they also check the wine's color, scent, and flavor.

The way Vince Vidrine understands it, wine legs were once an important assessment factor back in the days when taverns and restaurants were prone to watering down their wine. One thing that wine legs do seem to indicate is the amount of alcohol in a wine; the more alcohol it contains, the thicker the legs. This means that, in times gone by, drinkers would check the wine's legs to ensure they weren't being sold watered wine. These days, however, wine labels usually contain an indicator of the alcohol content — in fact, in the United States, it is mandatory for wines over 14% alcohol by volume to include this information on the bottle. (This is one of the reasons why it is possible to judge a bottle of wine on its label.) So, does modern wine labeling essentially make the process of checking wine legs obsolete? Well, no, not entirely, since wine legs are still of interest to scientists.

Physicists, in particular, get some kicks out of studying the Gibbs-Marangoni effect, which is a phenomenon in which liquids with different surface tensions flow in different directions. This is what causes the ridge of liquid to rise up a wine glass and those tears to run down. It turns out there's some other complicated science-y stuff at work, though, as evaporation comes into play and different compounds make themselves known. While the study of wine legs has yet to lead to any scientific or culinary breakthroughs, it's possible that a better understanding of how they work might lead to some tangible improvements for wine drinkers, including redesigned wine glasses that can better accentuate a particular wine's aroma. While there are many reasons to choose a specific wine glass, this research stands to supersede them all.