My research shows that screw tops are effective in removing the
chances of a bottle of wine being corked, but there are some who argue
that TCA (2,4,6-Trichloroanisole) which normally comes from cork,
still can come from wood which the wine comes into contact with. The
matter is hotly debated in wine circles. Some pro screw cap examples
are linked below.
?A 'Corked' wine is a wine that has been bottled with a cork that is
contaminated with TCA (2,4,6-Trichloroanisole). TCA contamination
usually comes from corks but can also come from barrels, other
cooperage or even, apparently, from wood within the cellar including
walls or beams. The term 'corked wine' is applied to all wines with
TCA contamination because corks are the souce of most of the problems.
The wine industry estimates that as many as 3% to 7% of all wines have
TCA contamination at levels that can be detected by consumers. Because
most people are not trained to recognize the smell and taste of TCA,
only a very small fraction of these bad bottles are ever returned to
stores or sent back at a restaurant.?
?Then there's that other tree product we put in contact with wine ?
the barrel, plus spin-off products oak chips and staves. Luckily for
devotees of oak-flavoured wines, TCA and other musty odours induced by
wood ageing are much rarer than from cork, but they can exist,
especially when barrel hygiene - usually sterilisation of empty
barrels with sulphur - is badly done. Worst offenders are producers,
usually traditional Europeans, who age their wines in extremely large
old casks which, if allowed to become tainted early in their life will
continue to impart impure flavours. Barriques - 225litre barrels of
French or American oak (and, increasingly, of Russian oak) - rarely
have problems of this type and anyway have a life expectancy of a mere
five years before being retired. However, ever-increasing use of
toasted staves inside stainless steel tanks - effectively a sterile
environment containing replaceable pieces of barrel section - is
effectively removing even the remote chance of deterioration from poor
?Cork is a major source of TCA in bottled wine, although experts
indicate that TCA in wine may be derived from sources other than cork,
such as from barrels or other sources of wood.?
The Hogue Cellars four year study of bottle closures (Google cache only)
Hogue Cellars Screw Cap FAQ
I hope this answers your question. If it does not, or the answer is
unclear, then please ask for clarification of this research before
rating the answer. I shall respond to the clarification request as
soon as I receive it.
corked screw cap