The emergence of screw tops in some age-worthy wines may soon have wine collectors standing up bottles in their cellars rather than laying them down. The jury is still out on how well screw tops perform in long-term wine aging, but the results of one winemaker’s test are promising.

In 1997, the Napa winery Plumpjack took a huge gamble by bottling half of its prestigious reserve Cabernet in with plastic-lined screw caps and the other half with traditional cork. Plumpjack general manager John Conover was fed with seeing his wine spoiled by tainted cork, so he decided to perform a test on his fine wine, which sells for up to $200 a bottle, to see if the screw caps passed the test of time. At the beginning of this year, Plumpjack did a taste test of the 1997 wines and found no difference between the screw cap and cork.

George M. Taber wrote an entire book on the subject, To Cork or Not to Cork, which sounds like a great read. You may remember George Taber from my recent post about the upcoming film, Judgment of Paris, based on his book. According to this review of To Cork, Taber provides a fascinating description of the cork industry, but concludes that we still haven’t found the perfect way to enclose a wine bottle.

Over the next few years, it’ll be interesting to see how many more producers convert to screw caps for their best wines. An incredible 90 percent of New Zealand wines are already sealed with screw tops, and Australia’s up there too at 60 percent. While we shouldn't be too quick to pop cork off the bottling line for fine wine, at least we’re at the point where many casual wine drinkers know that a twist-off bottle isn't a sign of plonk.