Known as TCA for short, this is the most common of flaws found in a bottle of wine. Industry standards put the amount of wine with detectable amounts of TCA at anywhere between 3-5%. This chemical compound can occur naturally in cork forests but is most often caused by corks that haven’t been cleaned properly after they are bleached, a process quite common for aesthetic purposes.
TCA is the cause of corked or corky wines, and causes flavors and aromas of wet cardboard or a musty, wet basement. The fruit in the wines is also muted by TCA. Wines affected by TCA can range from absolutely terrible to only slightly different from a pristine bottle, and it can be difficult in the more subtle instances to tell the difference.
The prevalence of TCA has spurred the growth of alternative enclosures such as screw caps and synthetic corks, as nothing is worse than opening a bottle of Bordeaux that has been carefully cellared for ten years only to have it taste like a basement.