As someone in the wine industry, I think I get a little complacent about the wine knowledge I have and forget what I believe is 'common knowledge', isn't really that common.
As we sell Tuscan Wine, a lot of the DOCG appellations are secured with Cork. I have had a number of people return bottles to be and say "how do I open it?" which has shocked me...Also, a number of people who won't buy our wine because they can't open the cork seal.
I personally, love stelvin caps...I love that the problem of Ullage and Corkage can be eliminated with one swift change. Obviously, europeans are a little slow with change so many European wines still come with cork, for appellation reasons as well.
So, lets take a look at some seals and see whether there really is much difference....
1. Natural Corks: These wine corks are one of the most popular, as they will keep the wine sealed for a considerable length of time, enabling the wine to mature slowly. They are cut from specially selected corkwood, and washed, sterilized and inspected before use.
2. Agglomerate Corks: Made from clean-waste product from natural wine-cork production, these corks are popular for low cost. They also ensure successful sealing and a good wine production.
3. Double Disc Corks: These corks also known as twin top corks are a combination of agglomerate corks and natural corks, the inside being agglomerate and the ends being laminated by natural cork disc. These discs come in varied qualities, and the highly technical stoppers are consistent in quality, density, function and price.
4. Synthetic Wine Corks: These are the modern equivalent to the traditional wine cork and come in various different colors. They seal well and don’t harbor bacteria.
5. Glass Corks: Vino-Seal is a plastic/glass closure released by Alcoa. Since its introduction into the European market in 2003, over 300 wineries have utilized Vino-Seal. Using a glass stopper with an inert o-ring, the Vino-Seal creates a hermetic seal that prevents oxidation and TCA contamination. A disadvantage with the Vino-Seal is the relatively high cost of each plug (70 cents each) and cost of manual bottling due to the lack of compatible bottling equipment outside of Europe.
6. Screw Caps: Screw caps or “Stelvin caps” are closures made only from aluminum material that threads onto the bottleneck. Compared to cork, screw caps prevent the wine faults of oxidation and of cork taint, and are easier to open. Screw caps have a much lower failure rate than cork, and in theory will allow a wine to reach the customer in perfect condition, with a minimum of bottle variation. Cork, of course, has a centuries-old tradition behind it, and there are also concerns about the impact of screw caps on the aging of those few wines that require decades to be at their best. Some argue that the slow ingress of oxygen plays a vital role in aging a wine, while others argue that this amount is almost zero in a sound cork and that any admitted oxygen is harmful.