Stoppers made of glass were already used in the 17th century to close wine bottles. They had to be cut specifically for certain bottles and tied to the bottle. They were in use until the 19th century, but were too expensive for widespread use. They are still used today for carafes (especially for distillates) or decanters. The German engineer Rudolf Gantenbrink (who caused a sensation in connection with a small robot in the Cheops pyramid) developed a "glass cork" that is firmly welded to the wine bottle. It is opened at a predetermined breaking point. From 2002, trial tests were carried out with it at Château Ausone (St. Émilion). In the meantime, however, the project was discontinued because hairline cracks formed at the breaking point, causing the closure to leak. After that, however, there were very successful products from other companies. One of the best-known glass closures is the Vinolok brand (USA Vino-Seal). See also other alternative closures under closures.
Pictures: Vinolok
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Markus J. Eser
Weinakademiker und Herausgeber „Der Weinkalender“