If wine fans needed any more proof that the romance of pulling a cork is passé, a 10-year study undertaken by the Australian Wine Research Institute (AWRI) vividly shows what happens to good wine under different closures over time. And it showed that TCA, or cork taint, is just one problem with corks.

The trial used thousands of bottles of a 1999 Clare Sémillon made at Leasingham and sealed with 14 different closures, including various corks, synthetic corks and screw cap. Once a year, researchers opened, analyzed and tasted a range of the wines in the lab.

The fresh-looking bottle on the left in the photographs below is the one sealed with a screw cap. All of the others show varying degrees of oxidation. According to the AWRI team, after a decade the wines sealed under screw cap showed an appealing aged character while retaining freshness in blind tastings.

When the study began, it was not to test screw caps, but to see how wines developed under various corks. "[We wanted] to determine which would be the best performing cork and we didn't expect the screw cap to be much of a factor," said Peter Godden, group manager at the AWRI. "It didn't take long to work out that it was going to be the most reliable performer and, as it turns out, the results are emphatic. The wine under screw cap was classic aged Sémillon and was wonderful to drink."

He added that there was huge variation in the results for the synthetic and cork closures, which he found to be of greater concern than TCA taint. "Most of the wines sealed with closures other than screw cap were completely undrinkable."