The figures are depressingly familiar to anyone involved in tasting or selling wine for a living. Familiar and depressing enough to raise a question-mark over the future of cork as a wine-bottle stopper.
Is it goodbye, then, to the romance still attached to the ritual of cork-pulling? Should we expect to see Chateau Lafite being sold in a bag-in-a-box or in a bottle that comes with a screw-top cap?
Perhaps not, but that such radical moves might even be considered is largely due to the cork taint TCA (short for 2-4-6 trichloranisole), which is formed in the cork by the interaction of phenolic compounds, chlorine compounds and mould. It is just as likely to affect fine wine as it is plonk. But since corkiness varies in degree from offensively mouldy to barely detectable, it is not always easy to spot.
Major problems of corkiness first surfaced in the Eighties, when quite large batches of corks were found to be affected by TCA. McWilliams, for instance, an Australian company, successfully sued its distributors for Adollars 2.8m (pounds 1.34m) for the loss of half-a-million tainted bottles from the 1982 and 1983 vintages. Even pounds 56-a-bottle Dom Perignon, the ultimate in champagne luxury, was afflicted at one time by poor corks.
TCA can also arise in oak barrels to produce a similarly mouldy effect in the wine. When Raimat, a modern Spanish winery near Barcelona, found barrels of cabernet sauvignon contaminated by TCA, it had no alternative but to burn the barrels and offer to replace affected bottles of its 1988 Abadia and Cabernet Sauvignon.
One explanation for the presence of TCA in the bark of the cork oak is thought to be the use of pesticides and fungicides in treating the bark. In the finished corks, it has been traced to the process of using chlorine as a bleach. But although chlorine treatment is on the way out, problems of corkiness still remain. TCA can develop, for instance, during shipment and storage, particularly in humid conditions.
One theory as to the root cause of the cork problem is that TCA is more likely to thrive on the larger fissures of young bark because cork oaks are being harvested too young. New forests are springing up to cope with the demand for cork, but, at a minimum of nine years old compared with around five not so long ago, cork is often more mature when harvested than it used to be. The reason could be higher cork prices that have resulted in an increase in the use of cheap corks.
Corks of all ages vary considerably in quality and price. Cheaper, low-grade corks can be badly pitted and fissured, making them more likely to contaminate wine with TCA than high-grade corks.
While on the German Wine Academy course, I visited the late Helmut Becker's cellar at the Geisenheim Institute on the Rhine. All the neatly binned bottles sported screwcaps, like bottles of plonk. Professor Becker took a mischievous delight in watching horrified reactions to this apparently barbarous method of keeping fine wine. But research at Geisenheim showed less deterioration in wines stored for five years with screwcaps than those with traditional corks.
Bottles sealed with a screwcap can also be stored upright, since the point of laying wine down is to ensure that the cork is kept moist and does not shrink.
It is not true, as was once believed, that cork lets a bottle 'breathe' minute quantities of air, allowing the wine to develop in bottle. The amount of air that can penetrate a cork is too negligible to be measured. It is not the air that gets in after bottling but the air already in the wine that works the necessary magic in a virtual vacuum.
Since science suggests that corks could be eliminated, the continuing presence of TCA provides a powerful incentive for the wine industry to look at alternatives. As Michaela Rodino, Saint Supery's winemaker in California, says, 'Most troubling is the difficulty in securing a consistent supply of reliably good cork. Everybody's talking behind closed doors about the inevitable. Sooner or later, corks have got to go.' Sooner, in the case of California's Stag's Leap Winery, which has announced that it will stop using corks altogether from this year. St Francis in Kenwood is trying out a synthetic cork called Polymar. Others are looking at the use of screwcaps.
Taking a leaf out of Professor Becker's book, the Qantas airline now serves wine in economy class from 75-centilitre bottles with screwcaps. It certainly makes the cabin crew's life a lot easier.
If the evidence points to screwcaps and the like, why has the industry not moved more rapidly? An inherent distrust of untried and untested synthetic materials may have something to do with it. And screwcaps look cheap. When the Sonoma wine company Glen Ellen sold its dollars 10 dolcetto with screwcaps alongside an experimental screwcap bottling of its dollars 5.99 varietal wines, consumers snapped up the dolcetto, but showed less enthusiasm for the cheaper bottles.
Why? Because, it seems, tops that screw on affirm the cheap wine image but have less effect on more expensive wines.
Somewhat belatedly, the cork industry has woken up to the problem of dodgy corks and is starting to fight its corner. Companies have introduced new techniques to combat poor corks and begun to clean up the raw material, the bark itself.
For instance, Sabate, a French company, has eliminated chlorine- related products in disinfecting the cork. At the same time it sources its own material to ensure the cork oak has not been treated with damaging biocides.
Portocork, too, a major supplier of corks near Oporto in Portugal, has developed a rapid washing and vacuum-dusting system to replace the old chlorine treatment. Peroxide is now in more common used than chlorine.
Meanwhile, what do you do next time you think the wine you have bought turns out to be corked? You are entitled to your money back, so re-cork it, take it back and ask for a replacement or a refund.
In a restaurant, invite the wine waiter to taste it. A corked bottle should not be seen by a wine waiter as an attack on his integrity and/or manhood. If you come across a stroppy wine waiter who disagrees with your diagnosis, order another bottle, compare the two and invite the wine waiter to do the same. And keep your fingers crossed that the second bottle is not corked as well.Reuse content