The cork conundrum

For the wine writer, corked wines are an occupational hazard, whose irritating frequency, like flies at a picnic, are tolerated without ever becoming acceptable. But if you open a duff bottle that you've paid for, you really feel the sting.

For the wine writer, corked wines are an occupational hazard, whose irritating frequency, like flies at a picnic, are tolerated without ever becoming acceptable. But if you open a duff bottle that you've paid for, you really feel the sting.

I know the feeling, too. When the first bottle from a delivery of the great 1998 Penfolds St Henri Shiraz turned out to be corked, the £22.65 quid down the drain hurt me as it would any wine buyer. So much for the romance of cork-pulling.

At Vega Sicilia, Spain's most historic, long-lived red, the cork problem with their 1994 Valbuena led the winery to develop a system of double-testing corks for chemical and tasting analysis.

They now reject two out of three corks tested, but even so, the 1999 Valbuena I tasted in situ still showed signs of cork taint.

One of the problems with TCA (short for Trochloro anisole, the mouldy cork taint) is that its effect is relative, not absolute. For every badly corked wine, you're likely to come across two or three borderline cases in which a small level of TCA has taken the edge off a wine's fruit-freshness and fragrance. That's the main reason why the extent of the problem is underestimated.

If cork is the weakest link in the wine production chain, consumers have yet to accept the alternatives. The screw cap, or Stelvin closure as it's known, has been proved to be technically superior. But natural cork sends out an upmarket message, and the wine industry has to deal with that. While the Australian and New Zealand wine industries have taken an impressive lead, European and other New World producers have generally dragged their feet.

A screw cap can cost nearly 50p a bottle more than cork. A switch will cost money and the wine industry has used the if-it-ain't-broke-don't-fix-it principle to justify its inertia.

The move to screw cap might have happened sooner if those few bottles that had them weren't so exorbitant.

So far, the screw cap's superiority over cork has been associated almost exclusively with white wines, especially aromatic whites like Sauvignon and Riesling. In a thoroughly well-argued booklet, "Screwed for Good" (www.cellaringwine.com), Tyson Stelzer, an Australian writer, makes a convincing case for screw caps on red wines. According to Stelzer, the case for red wines made for drinking young is open-and-shut. For reds that need ageing, the arguments are more complex.

When a top red might have a 50-year life, the wine industry needs to be convinced that screw caps will be "as good as" corks over that period. Another fear is that a screw cap might create Peter Pan wines - so effectively sealed that they don't age.

On both issues, Stelzer's research comes down in favour of screw caps.

He shows that cork becomes more erratic over time while the screw cap is better at prolonging the shelf life of wine generally. And producers are increasingly coming round. Stelzer points out that the use of screw caps has other potential benefits that could rewrite the rules of cellaring.

They are less susceptible to temperature variation and the lack of humidity that afflicts corks. So it looks as if not only will we be able to store bottles upright and throw away our corkscrews, but even the dusty, cobwebbed cellar itself could become as much an anachronism as cork itself.