Why Does Wine Cry?

Dan Quinn a PhD student at Princeton University studying theoretical and experimental fluid mechanics in the Mechanical and Aerospace Engineering Program, is now one of the web’s most engaging wine teachers as well. After attending a lecture in which his professor used “legs” or “tears” on the side of a glass of wine to explain surface tension, Quinn shot home video footage of what happens when red wine is swirled in a glass. Viewed at twelve times its normal speed, the footage demonstrated surface tension in action.

Quinn applied the narrative techniques he picked up as president of the Filmmakers Society at the University of Virginia to share the science behind “Why Does Wine Cry” with the YouTube audience. The results are mesmerizing. By combining the high-speed footage with simple animation, concise voiceovers and trip hop music by Emancipator, surface tension becomes as accessible as any subject covered by School House Rock.

This is what you’ll learn: Wine is mostly water and alcohol. Water has higher surface tension than alcohol. When you swirl a glass of wine, the alcohol in the wine on the side of the glass evaporates faster than the alcohol of the wine in the bowl. Consequently, the wine on the side of the glass has a higher percentage of water and a higher surface tension, causing it physically to pull droplets of wine up the side of the glass. What determines the size, shape and density of a wine’s “tears” or “legs” remains unknown -- though it seems likely that Dan Quinn will be the one to find out.