Wine Glass Legs – Marangoni Effect
Have you ever wondered?
Why do you get “legs” or “tears of wine” in your wine glass when you swirl your wine? I’m sure over the centuries many people swirled their glass and have had deep conversations what causes it.
I can only imagine the questions. A few that came to me initially are: What causes the wine to create the legs? What does it really mean? Are more or less legs a sign of the quality of your wine?
So a bit of history. This phenomenon was first identified in the so-called “tears of wine” by physicist James Thomson in 1855. The general effect is named after Italian physicist Carlo Marangoni, who studied it for his doctoral dissertation at the University of Pavia and published his results in 1865.
You can see a falling line in the background shadow
How does it work? Alcohol evaporates quicker than water. As you swirl your glass the alcohol evaporates, it crawls up the side of the glass. There’s a film of water on top of this alcohol and it’s pushed up in an arch. Eventually, gravity will win, the water surface tension will be broken, and water will run back as tears or legs back into the glass.
The more alcohol you have, the more of the Marangoni effect occurs, and the more legs you will see.
So, this has no effect on quality unless you think that more alcohol is better.
Life is too short to drink crappy wine. Expand your palate and keep trying.