What does Natural cork mean?

Natural cork is a stopper punched from the bark of the cork oak; the traditional closure, letting very small amounts of oxygen into the bottle.

Also known as: Cork, Cork stopper

Natural cork is a stopper punched in one piece from the bark of the cork oak, Quercus suber. It is the traditional closure for wine and is still used for a large share of the world's wines, especially those meant for ageing.

Cork oaks grow mainly around the western Mediterranean, and Portugal accounts for roughly half of world production. The tree is not felled. The bark is stripped for the first time when the oak is about 25 years old and then roughly every nine years, and cork from the first harvests rarely becomes wine stoppers.

Cork is elastic and seals the bottle neck well, but lets through very small and somewhat variable amounts of oxygen. This has long been thought to help the slow development of wines that are aged. Bottles with natural cork should be stored lying down so the cork stays moist and does not dry out.

One drawback is the risk of cork taint, where the compound TCA gives a dull, musty smell of damp cellar and mutes the fruit. The share of affected bottles has fallen sharply thanks to better production and testing, but the risk remains. That is why sommeliers often taste a wine before serving it.