Since the vintage 2004, we use screw caps on our "Tradition" wines and on some wines of the range "Vins de terroir". The wines bottled with this method are fruity ones that should be drunken within 4-6 years. "The evolution of a wine doesn't require oxygen. The wine develops its organoleptic capacities in a reductive environment where it acquires superior properties of quality." That comment from Pascal Ribéreau Gayon (treatise of oenology, 2000) should disrupt stereotyped speeches that make the oxygen the only element for the improvement of the wine.
Between 2003 and 2008, the among of regular bottles (75 Cl.) with screw caps has sharply increased from 300 millions to 2.5 billions in an overall yearly production of 17 billions of wine bottles across the world (Source : Le Figaro Newspaper, France).
New Zealanders and Australians are well-known for using that system. 90% of the bottles in New-Zealand and 60% in Australia are with screw caps. In Europe, Switzerland has been using it successfully for more than two decades for their white wines that are known to be oxidation-sensitive. Thanks to screw cap, quality of our wines does not change; they remain fruity and well-balanced. It's the best way to preserve a wine, to keep it as intact as when it has been bottled. And screw cap has also the advantage that it can again be closed after using, you need no cork-screw, you can take the bottle for a picnic or you can lay it into the refrigerator without risk of leaking out. Today, Michel Laroche's "Grands Crus" that are closed with screw caps are served in restaurants which are awarded with Michelin stars. Other examples: André Lurton in Bordeaux region with a part of his white wines 2004 of Château La Louvière, Bonnet and Couhins … These last ones use the joint Saran Film Etain that provides an excellent sealing.
An extremely qualitative system for white wines.
Stelvin screw caps are provided with the joint "Saran Film Etain". It consists of a heart of expanded polyethylene on which a layer of tin increases the final sealing of the Saran film that is in contact with the liquid. That type of screw cap is perfectly suited for white wines. STELVIN concept meets the new consumption requirements of today: this screw cap allows to keep qualities of wine thanks to a perfect liquid-tightness, a controled regularity of exchanged gases and, especially, no more TCA-molecul.
Furthermore, use of bottles is improved with an easy opening and closure. The bottle may be stored and carried in all positions, upright, laying or upside down. Regarding price, bottling with a screw cap is today roughly 10 to 20 % more expensive than traditional systems, as it needs, not only the screw cap, but also specific bottles (produced in smaller quantities, thus more expensive) and new equipment.
Comparative studies of bottle closures, realized by the estates Laroche at Chablis, Burgundy-France, estimate that the SO2 contents are nearly stabilized with the screw cap in comparison to other bottle closure systems (agglomerated cork, synthetic cork …). This result is also confirmed by the Vignobles du Peloux, Vaucluse-France, where use of screw cap has even enabled a slight reduction of the sulfidizing level when bottling. In the region of Côtes du Rhône, the Institute rhodanien that compares several sealing systems has demonstrated that, after one year of bottle closure, screw cap seems to guarantee the best harmony for wine. In Australia, the AWRI (Australian Wine Research Institute) that compared fourteen types of corks, already showed that screw cap allows a better conservation of the total SO2 rate that is free in the bottle. It reduces the sensitivity to a brown color formation and ensures the preservation of fruity notes, without oxidation or notes of advanced fruit. The study even explains that screw cap allows to achieve "ideal conditions for keeping a wine in such a bottle".
Having said that, screw cap is even appropriate for wine that will be kept. Screw cap's life is estimated at more or less twenty years.
Geneviève Teil, sociologist at the french INRA institute, explains that "we don't have to prove to people that screw cap is better for them, but to insist on the fact that it is good for wine". Her thougt is the following: when the producer who, until right now, lets consumers in doubt with complex labels, changes his attitude and worries about the easy opening of bottles or about cork taste, customers will wonder wether the producer is not sparing money, neglecting consumers. But, if producers ensure consumers that this change only aims to increase the quality of wine, it's all right. "In France, people must still make efforts for wine", says Geneviève Teil, "the practical argument that wine bottles with caps are easy to close again does not work. Traditionally used corks have all characteristics that ensure a good sealing, but since it is a natural product, it has weaknesses such as the presence of TCA that is at the origin of "cork taste". Taking into account those reports and having 25 years of experience with the product, Alcan Packaging Caps developed the concept STELVIN that complies with each of these requirements:
- No risk of TCA development
- Allows wines to keep their typical characters
- Neutral and stable cap - great aesthetical quality
- Complis with the consumers' requirements of comfort as well as traditional aspects.
Pechiney developed screw cap in the seventies with STELVIN system. And with it, the specially adapted BVS bottle neck ring for that cap. Swiss market was then the first one to widely adopt STELVIN concept. In 2001, the USA, Australia and New Zealand began to change for STELVIN concept for their white and red wines. 2002 was the year of confirmation for those countries as well as for Chile and Argentina. France and Germany then began using screw cap.