Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions , from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics .

Dear Dr. Vinny,

Someone told me that if you put an old penny in a glass of wine, the wine may taste better. Is that true? Why?

—Thomas K., Northbrook, Ill.

Dear Thomas,

It is a neat trick, but it only works with certain pennies, and certain wines. Pennies minted before 1982 were made of mostly copper, not zinc. And copper reacts with mercaptans and helps them dissipate. What are mercaptans? They are a stinky sulfur compound sometimes found in wine that’s a natural byproduct of fermentation, and amplified by certain winemaking practices.

Mercaptans are harmless, but sometimes they get in the way of appreciating a wine, and create what are sometimes called “reduced” notes. That skunky odor might blow off when you swirl your glass or decant the wine, but the penny trick works too.

—Dr. Vinny