The PlumpJack Group and UC Davis have teamed up to conduct a two-year study on the effectiveness and quality of screw cap wine closures.

The study aims to resolve the ongoing debate over whether wine quality and ageability is compromised by the use of screw cap closures, compared to the use of natural or synthetic corks, said Andrew Waterhouse, professor of viticulture and enology at UC Davis.

All three closure methods — natural corks, synthetic corks and screw caps — are being studied. The results will be published at the end of 2013.

"Oxygen is the biggest culprit for wine — it affects taste, color and the aging process," Waterhouse said in a statement. "With this study, we hope to scientifically analyze the effectiveness of other closure methods, and thereby to provide information and direction for the industry."

PlumpJack pioneered the use of screw caps for premium wines more than 10 years ago.

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