Shall we end up forgetting the typical wine-waiter's gesture - sniffing the cork before serving the wine? It looks as though we may have to. Experts predict that within a few years at least 5 million bottles will be using biodegradable plastic corks. Shocked? But a lot of producers take the idea seriously, especially for wines to be drunk young.
Cork is used because it allows a limited exchange between the inside and outside of the bottle. This exchange is held to be essential to make the contents evolve and reach that richness and complexity which only a wine aged for years in a bottle with a natural cork can acquire.
The characteristic smell of cork, the other side of the coin, is due to the presence of a parasite, Armillaria mellea, a fungus which develops in the main roots or at the base of the cork oak. It is actually easy to identify this fungus; trees attacked by Armillaria have white cork and can easily be eliminated. More frequent are 'false' cork scents due to changes in the cork or the wine due to use of barrels or barriques with bad quality staves, and mouldy smells due to the development of micro-organisms in the cork and to unsuitable cellar situations (too damp, for example) which have a negative influence on the cork.