quote:Originally posted by Roentgen Ray:
One of the risks of an airtight seal, that you can get from a screw top, or rubber stopper, is that the wine can become reductive, which will make it smell of rubber.
As Greg pointed out earlier, synthetic corks are FAR from airtight, and have, in fact, the highest rate of oxygen transmission of any commercial closure. Wines under synthetics-- especially the molded type--don't keep long, with an upper range generally regarded to be five or six years for the more tannic reds.
And on a technical note, closures do not cause or make wine reductive. Wine is generally made in a reductive environment and is therefore bottled reductive. Reduction is a winemaking issue, and the closure can ameliorate or exacerbate the manifestations of the condition, but they cannot cause it.
To wit, one could bottle an oxydized wine (e.g. Madeira) under tin wad screwcap (the type with the lowest oxtrans rates) and it will never, ever be reductive.