There are few studies that have examined the analytical
properties of wines bottled with various types of closures.
A detailed Australian study concluded that an un-oaked
Semillon wine showed significant oxidation with some
synthetic closure products, TCA-associated taint with the
natural corks and composite cork products, and some reduced
character in the single screwcap product evaluated
(Godden et al. 2001). In a review of that study, it was
noted that wines closed with the single screwcap treatment
and evaluated at 36 months postbottling were relatively
defect-free and had lower overall oxidative character,
higher SO2 retention, less browning, and well-preserved
fruit character (Francis et al. 2003). Other research has
supported the assertion that synthetic stoppers are suitable
wine closures because of low spoilage rates and
lower variability when compared with natural corks (O’Dell
2000). The production department at Hogue Cellars
(Prosser, Washington) has worked with synthetic closure
alternatives since 1991. These synthetic closures have
solved the problem of cork taint, but wines seem to age
quickly with synthetic closures and there have been problems
with extracting the cork from the bottle.
While there is some limited research reported on wine
quality, few studies report consumer attitudes toward different
closures. A poll conducted by BRS Group examined
wine drinker opinions and attitudes on closures, and results
showed that regular and occasional wine consumers
have highly negative responses toward screwcaps and
other noncork closures. Consumers also believe the wine
industry is moving to alternative closures to save money
on packaging, not because of wine-quality concerns
(Cartiere 2004). Results of a recent market study conducted
by Tragon Corporation and the Australian Wine