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ask dr. vinny

Hello there! I'm Dr. Vinifera, or "Vinny" for short. Ask me your toughest wine questions, from the technical aspects of winemaking to the fine points of etiquette. I hope you find my answers educational and even amusing. Looking for a particular answer? Check my archive and my FAQs.

Dear Dr. Vinny,

What is that rubber smell you find in so many young wines? Where does it come from?

—Federico C., Mendoza, Argentina

Dear Federico,

What you’re picking up on is probably a sulfur compound—my guess is mercaptans. These compounds occur naturally as a byproduct of fermentation, and they can be amplified by certain winemaking practices. They aren’t harmful, though they can be unpleasant or dominate a wine’s other notes, and given time, sometimes they seem to blow off.

Here’s a neat trick: if you have an old copper penny (dated prior to 1982, when they became mostly zinc), you can drop it into your wineglass and the metal in the coin will react to the mercaptans and help them dissipate. It might seem like magic, but it’s just chemistry.

—Dr. Vinny

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