Cork taint

Cork taint: an unpleasant, 'musty' off-flavour caused by a faulty cork (French: bouchon).
It is very rare in champagne, because the houses take particular care over the selection of their corks and over their design (additional cork discs at the foot of the champagne cork). Some cork producers may occasionally have disinfected their corks inadequately, which allows mould to creep in. 'TCA' (trichloroanisole) then develops in the wine. Sometimes the cork is also simply used as a 'scapegoat' for other faults in certain wines (see also Cork).

Cork taint in champagne is a frequent topic among wine lovers and is usually found very unpleasant. It is a specific off-flavour that can arise when the cork of a champagne comes into contact with certain chemicals, or when the cork itself is not up to standard. To understand cork taint and its effect on champagne properly, it helps to look at several aspects.

Where cork taint comes from

Cork taint, also known as 'cork dumbness', is caused by the molecule 2,4,6-trichloroanisole (TCA). TCA is a chemical compound that forms when corks, which are made from the bark of cork oaks, react with chlorine compounds. This reaction can produce a musty, mouldy smell that harms the taste of the champagne. Although TCA is present only in tiny amounts, even very low concentrations can be disturbing.

How to recognise cork taint

Champagne with cork taint often shows unpleasant aromas reminiscent of damp paper, old cellars or mouldy cardboard. The taste tends to be earthy and can mask the fresh, fruity notes of the champagne. Instead of the fresh citrus, crisp apples or lively blossom aromas you would normally expect from a high-quality champagne, you may find a flat, musty taste. The perlage, meaning the fine bubbles, can also suffer, as the delicate aromas can be strongly diminished by the taint.

Viticulture

Effect on champagne

Champagne is particularly exposed to cork taint because it usually ages for a long time in the bottle. During ageing the cork can come into contact with the sparkling wine, which increases the risk of TCA passing into the champagne. While the champagne matures in the bottle, even corks of the highest quality cannot always be guaranteed, as they are made of natural materials that are inherently prone to contamination. It is therefore crucial to check the quality of the corks and the storage conditions in order to keep the likelihood of cork taint as low as possible.

Avoiding cork taint

To reduce the risk of cork taint, many champagne producers now use alternative closures such as screw caps or synthetic corks. These alternatives give better control over possible contamination and lower the risk of TCA. Synthetic corks and screw caps are largely immune to the problems associated with natural corks and so ensure a more consistent quality of the champagne.

What to do if a bottle is corked

If you find that a champagne shows cork taint, it is usually hard to remedy. The only solution is not to drink it and, if the bottle is defective, to make a complaint to the merchant or producer. Many producers and merchants are aware of the problem and offer a replacement or refund if the champagne is genuinely affected by cork taint.

Conclusion

Cork taint is a serious problem for champagne lovers, as it can considerably spoil the enjoyment and quality of the drink. While the industry is making progress in preventing it, it remains important to pay attention to the quality of the champagne and the condition of the closure. Using synthetic corks or other alternative closures can help to minimise the risk of cork taint and ensure that the champagne is enjoyed at its best.