Keyword: Screw cap
A special and increasingly popular closure type (English Screw cap or twist) of wine bottles as an alternative to Cork (cork) from oak bark. These are made of corrosion-free metal (usually aluminum alloy) with an internally located sealing layer Polyethylene (PE), PVDC (Polyvinylidene chloride) manufactured or tin foil. In the beverage industry, this is also known as MCA-closure (MCA = aluminum metal closure). The emotionally charged debate whether it constitutes "cultural loss" is connected, are compared with the relatively inexpensive production and the fact that that the problem of Corked can be avoided with natural corks. Moreover, the argument is often used for the pro-"pop" as a sensual pleasure is not valid, because a bottle should be opened professionally as quietly as possible (this is especially true for sparkling wine).
In airplanes, for example, you can get for decades only wine bottles with a screw cap. Here you will find no one here, because the advantage of a simple opening in the cramped airplane is obvious. A further advantage is that it bottles can be closed very easily. Even the look has been successfully tried to take the rejection of the cork-friends over alternative closures into account. Externally, such rotational closures are no longer recognizable as such. The first use in wine bottles was in the late 1970s in Australia, as the Pioneers are the producers in the Clare Valley (South Australia). Soon after came from many producers New Zealand and California .
Unlike a sealed means of cork wine bottle with a screw cap of the empty space in the bottle neck is substantially greater. The volume is 15 milliliters, which means a relatively high Oxygen of 4.2 milligrams. Especially with a cold bottling remains in the air space (and thus oxygen). Therefore, when filling an air displacement by carbon dioxide advisable. An often-voiced argument against screw caps is that the much better seal than the cork no oxygen is possible, but for the bottles in was essential. This is according to the opinion of most experts and chemists rather an argument for the screw cap. Because if the oxygen in the bottle located in the bottleneck (now often inert gas ) and rich in dissolved form in the wine itself for the complex Aging by far.
This was also a test for a Riesling Tasting in Sydney Australia in 2003 impressively underlined. A large group of leading manufacturers from around the world was presented with a Riesling. The age was estimated by the experts to between six and ten years, but actually acting it is a 1982-Riesling, which was then sealed with a screw cap. This suggests, at least in this case suggests that the slower maturation of such closures is going on, but causes an almost perfect seal by turning the lock no loss of quality. Whether this is true in general, of course, can not be derived from a single example. But there are numerous other examples that will be adversely affected even with an absolutely tight seal, the ripening of the wine in the bottle in any way. This fact was also, for example, by several tests in the German Research Institute Geisenheim (Rheingau) fully confirmed.
Beginning of 2002, the Australian multi- Southcorp is aware that all Rieslings (including Penfolds , Rosemount Estate and Wynns ) Of the class of 2002, with screw cap can be filled instead of natural corks. From the year 2004/2005 all white wines from Penfolds is thus closed. This producer also makes has been very successful trials in 1995 with top reds. It was no problems are found, the wine is aged completely uniform. Followed in 2004, then as the first Cru ClassÃ© wine from the Bordeaux, the ChÃ¢teau Couhins-Lurton (Graves), which closes its best to be counted in Graves white wine, and two other white wines from two wineries in the Lurton empire with a new screw version .
More and more wine producers are converting to this technology. Especially in New Zealand and Australia with 90% with 60% of the share of alternative closures is extremely high, with much the highest proportion of rotary closure (status 2008). According to a March 2009 estimate published by the Italian manufacturer Guala screw the screw cap has reached a worldwide share of 15 percent. In 2008, global sales rose screwdriver in the wine region around a quarter to about 2.5 billion pieces. Significant increases were achieved in Germany (one third screw cap, plastic and natural cork), France, in Europe, with around two thirds of the leading wines with screw cap Austria, Italy and Spain, and Argentina and Chile. A well-known brand is STELVIN , which has almost become a synonym for this closure. See also other alternative types of closure under Closures .