Wine study favors screw caps

Nation's Restaurant News, Sept 20, 2004

SAN DIEGO -- Screw cap closures hold fruit and maintain freshness better than natural or synthetic corks do, according to a study conducted by Hogue Cellars, a winery in Washington's Columbia Valley. After tasting a 1999 Merlot and a 2000 Chardonnay at six-month intervals for 30 months, a panel comprising Hogue winemakers and other trade professionals found that wines closed with natural corks had low to medium levels of cork taint, while those closed with synthetic and screw caps showed none.

However, the panel found that wines closed with synthetic corks for more than two years showed oxidation characteristics, such as less fruit aroma and taste as well as browning of both the Merlot and Chardonnay.

The screw caps did seem to slow the aging process but were preferred over synthetic corks, which were preferable to natural ones.