What effect does wine bottle closure type have on perceptions of wine attributes?

We examined the effects of an extrinsic attribute of wine—closure type (natural, screw, synthetic, or glass)—on perceptions of intrinsic attributes (appearance, taste, bouquet, and overall quality) by comparing two separate samples of tasters to determine whether differences exist. A convenience sample of students, parents, faculty, staff, and community members in a college town in the northwestern United States participated in the study. The findings confirmed the positive halo effect of natural corks when compared with screw caps and synthetic corks. More specifically, wine thought to have been poured from a bottle with a natural cork closure registered significantly higher ratings on appearance, bouquet, taste, and overall quality compared with wines closed with screw caps or synthetic cork closures, but not those with glass closures. Our findings suggest that glass stoppers could replace natural corks without generating significantly negative effects on perceptions of intrinsic wine attributes.