The pop of a cork coming out of a freshly opened bottle of wine is a beautiful sound. Unfortunately corks have come under scrutiny as a leading cause of a flawed bottle. While a bad cork is the culprit for a specific type of wine flaw, there are a few misconceptions as to what a freshly popped cork can reveal about the wine held within the bottle.
Cork Taint: Taint occurs when bacteria contaminate the cork and reproduce in the bottle. Wines that encounter a bacteria filled cork are said to be “corked.” The most common chemical compound that this interaction creates is 2,4,6-Trichloroanisole (TCA), and this gives the infected wine its distinct “corky” smell. Although many claim to be able to identify a “corked” wine by smelling the cork itself, the only true way to recognize a corked bottle is to pour a glass and smell the wine itself.
Moldy Corks: Have you ever cut the foil off a bottle and noticed hints of mold at the top of the cork? The cause of the mold between the foil capsule and the cork is too much moisture in the storage area of the bottles, but never a problem of the cork or the wine. Wine cellars are generally maintained at 50-59° Fahrenheit in order to let the wine “mature” slowly and humidity plays an important role in the storage area- If the cork dries out, it will contract and allow an excessive amount of oxygen to come into contact with the wine producing an oxidized wine. The humid environment is the best way to store wine but it also creates a perfect place for mold to form on the tops of corks under the foil. This mold does not touch the wine and can be wiped away with a damp cloth before opening and enjoying your bottle.
Stained Corks: A stained cork does not mean that your wine is bad or spoiled. Sometimes corks are placed into bottles too-full with wine. Slowly, over a few days or weeks, some wine will leak out of the bottle until the pressure neutralizes. Since these bottles are stored upside down or on their sides, the cork will be stained.
Tartaric Crystals: Encountering a wine with small crystals floating in the bottom of a bottle or those adhering to the cork is not a sign of a flawed wine. In fact, these crystals, called tartrate or wine diamonds, are a natural by-product of unfiltered, unprocessed find wine and are totally harmless.
So the next time you open a bottle and encounter a funny-looking cork, make sure to smell and taste your wine to prove to yourself nothing is wrong before dismissing the bottle as flawed.