Foil caps use bacteriological warfare to secure their future on bottles of wine

Foil caps are not just a marketing part of packaging – scientific research has shown that they play a protective role on bottles of still and sparkling wine”, is the confident claim made by the world’s leading foil cap producer, Crealis Group. The manufacturer also adds in the statement that the caps “are an effective hygiene shield against the spread of bacteria and mould”.

Commissioned by the foil cap manufacturer, the research conducted in 2024 by CSI laboratories compared bottles with and without caps that were immersed for a few seconds in a bacterial breeding ground. After the bacterial culture, no bacteria or mould developed on samples of bottles with foil caps, whereas the spread of both was visible in the absence of caps. CSI laboratories therefore concludes that “the test has proven the critical part played by foil caps in maintaining hygiene around the neck of the bottle and the closure” and that “adding a foil cap forms a physical barrier which impedes microbial contamination similar to what is produced by businesses and consumers and the spread of air-borne or contact germs”.

“The purpose of this study was to observe the hygiene barrier and not the oxygenation aspect. There are probably other protective roles that can be observed on the integrity of the closure”, stresses Crealis Group. The company adds that it is working on “the sustainability aspect” with “new, more sustainable and recyclable materials”.