Plastic “corks” are replacing natural cork for wine stoppers—and for a good reason. During the 1980s and early 1990s, bad cork was traced to the fungal contaminant called 2,4,6-trichloroanisole, TCA. Not only is it not good to drink such a fungus, but TCA also flattens the taste of the wine—removing the flavors the winemaker worked so hard to produce.