Cork

Champagne is only ever closed with the finest natural cork.

The cork comes, as a rule, from Spain, Portugal and the western Mediterranean. Botanically speaking, cork is the bark of the cork oak (Quercus suber), a tree that can live for up to 350 years.

The trees are stripped for the first time after about 25 years. This first cork, however, is not suitable for making bottle stoppers, as it has an unclean smell and taste. Only eight to 15 years later does the cork oak yield cork of the right quality, which is then stored for a further nine months or so. Visually, the quality of a cork can be judged by the number and size of its pores: the larger the pores, the poorer the quality.

A champagne cork starts out cylindrical, like an ordinary wine cork, but about three centimetres in diameter. The cork tissue is densely packed with cells that are water-repellent, filled with air and elastic. A four-jaw corking machine squeezes the cork down to about two centimetres. It is then driven mechanically about two centimetres deep into the neck of the bottle. As it expands again, it forms an especially watertight seal in the neck. These unique properties make cork ideal for closing champagne, because it is not only a matter of keeping moisture out, but also of protecting against the escape of the precious carbon dioxide. In addition, the champagne cork is given a small metal cap (the plaque), which stops the wire from cutting into the cork. The traditional wire cage (muselet), which adds further security, is then fitted.

The cork is often made the scapegoat for other wine faults that actually come from the wine itself or from poor storage. Sometimes, though, the cork really is the culprit behind cork taint. Among other things, this happens when fungi creep into the cork tissue, give off metabolic by-products and produce the chemical precursor of the compound that causes cork taint in the wine (see also 'Enemies of the cork' below).

Henri Abelé Champagner Korken

The cork of a genuine champagne must bear the word 'Champagne'. For vintage champagne, a year must also be shown.

The shape of the cork from an opened bottle also tells you how long it has been in the bottle:

If it widens at the foot, it has only been in the bottle for a short time (possibly less than a year). A cork of this kind is called a juponne.
* If its foot stays narrow, the champagne is older and was corked a long time ago. A cork of this kind is called a cheville.

“Only eight to 15 years later does the cork oak yield cork of the right quality, which is then stored for a further nine months or so.

Champagne corks are generally fitted with two additional discs of natural cork at the foot (this end piece is called the 'miroir'). These discs act as an extra barrier against liquid and carbon dioxide.

The world record for the free flight of a champagne cork stands at 54.18 m (Woodbury Vineyards in New York State, USA).

Enemies of the cork

ImageTo sterilise corks, producers use chlorine and SO². During bleaching, chemical reactions between micro-organisms and the chlorine can occur, which may give rise to (unpleasant) aromatic compounds. The compound TCA (trichloroanisole) is considered chiefly responsible for the notorious taste of cork taint. Over time, a wine picks up these unwanted flavours through contact with affected corks. Modern cork merchants now use, among other things, GC/MS testing systems (gas chromatograph with mass spectrometer), which can detect the tiniest traces of TCA in corks. Champagne houses, large and small, take the greatest care in choosing new corks anyway. The house of Mumm, for example, puts every new delivery of corks through a costly test: 200 bottles are sealed with the new corks and stored for six weeks. The house's oenologists then open these champagnes and examine them closely. If more than three of the 200 bottles show even a suspicion of cork taint, the whole delivery of corks is rejected.

Mould is also very dangerous for corks. It can be introduced through inadequate sterilisation, improper transport and/or unfavourable storage of the corks at the grower's. Later on, mould can also attack the private collections of wine lovers, who either ignore important storage rules (for example, 'do not store next to fruit') or are, unfortunately, forced by circumstances to keep their wines in rather unfavourable conditions. Happily, a distant relative of wine, humble vinegar, is regarded as an enemy of mould.

Another dangerous enemy is the cork moth (Nemapogon cloacellus). This small moth (about 7.5 mm long) regards the cork as an ideal place to lay its eggs. The caterpillars that result (cork worms) feed on the cork, which often loses its seal as a result (the wine is then, sadly, generally ruined). Besides examining the cork itself, small 'cork crumbs' around the neck of the bottle or on the floor are a sign that there may be a problem of this kind. Champagne at least offers some defence against these unwelcome visitors: the tight wire cage, the capsule and the handsome foil cap make access considerably harder for the moth. The author also reckons that you might, in some circumstances, tolerate spiders in your cellar, as they would very likely enjoy a moth or two.

Boizel Champagner Korken und Flasche

The cork as a lucky charm

When serving, you could introduce your guests to an old tradition: carefully cut a slit in the underside of the cork, slip any coin into it and hand the combination to someone. According to legend, as long as the coin and the cork stay together, good luck stays faithful to the recipient.

It is also rumoured that if a champagne cork is given to a lady, she only needs to spend three nights with the cork under her pillow before she dreams of the man she will eventually marry!