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,
I'm in a wine-appreciation course in which my instructor insists that the cause of "cork taint" is a yeast called brettanomyces. However, I was under the impression that cork taint and brettanomyces were two distinct issues. What do you say?
—Daniel, Grand Forks, N.D.
You're correct that cork taint and brettanomyces are two different things. For starters, one is a chemical compound and the other is a yeast.
A wine afflicted with cork taint—a "corked" or "corky" wine—has been tainted with a compound called 2,4,6-trichloroanisole, or TCA, which causes us to perceive the wine as having musty, dank or moldy aromas and muted flavors. It reminds many folks of wet cardboard, damp cement or the smell of old books. TCA is created by an interaction of mold, chlorine and phenols (which are organic compounds found in plants), and can develop in natural corks. But corks are not always the source of TCA, since it can also originate in cardboard cases, barrels or wood pallets. Indeed. Entire wineries have been contaminated with it.
Brettanomyces, or "brett," is a yeast, and since it can ruin a wine, it's generally considered a spoilage yeast (although it's considered a friend to beer makers). At low concentrations, some people find that it can add a pleasantly spicy component to a wine. At higher levels, it gives wine a barnyard, horse-stall or metallic note. Brett can develop at practically any stage of production, but it's more likely to be found in a winery than in a vineyard, often hiding out in barrels. When it takes residence in a cellar, it can be really tricky to get rid of.
Thresholds of perception (and tolerance) for TCA and brett vary, so there are some people who don't notice these flaws, others who might mistake one for the other, and more sensitive tasters who find wines marked by these flaws undrinkable.