SCREW CAPS CONTINUE THEIR RISE TO ACCEPTANCE

The October 31, 2007 issue of "Wine Spectator" includes an article by Matt Kramer on the use of screw caps as closures for wine bottles. He starts by relating a story of a colleague who tasted two identical bottles of a 2002 chablis except one had been sealed with a screw cap and the other had been sealed with a cork. The wine from the screw capped bottle was "much fruitier" than the wine in the corked bottle. He said that this was consistent with his experience. Wine from screw capped bottles "invariably emerges fresher, fruitier and more precise in flavor definition."

He says that a recent study in France tested the amount of oxygen that gets into a bottle sealed with screw caps versus both natural and artificial corks. Not surprisingly, screw caps are best at keeping oxygen out. I was surprised to learn that natural corks do a better job at it than artificial ones. I thought natural corks would "breathe" better than artificial ones. Perhaps they do, but in doing so they apparently let less oxygen into the bottle. In addition, the higher quality natural corks let in less oxygen than lower quality ones.

Wineries do have to make some adjustments in the way they make wine if they use screw caps. They need to take measures to prevent the development of sulfide characters.

One other fact mentioned in the story. Bottle orientation (upright or on its side) has little impact on oxygen infiltration. Also, the need for humidity in the storage of bottles is essentially not needed. While important for wine stored in barrels, the humidity level inside bottles is maintained at virtually 100% and the humidity outside is of little consequence.