Cork has been used as an enclosure for wine bottles since the 1600s. The great elasticity of this substance, along with the fact that it is nearly impervious to leakage, makes it an almost perfect natural enclosure. This was a great technological advance considering producers were using oil soaked rags up until the mid 17th century. Now, producers are also using alternative enclosures, and we are going to delve into the pluses and minuses of all.
- Cork. The most traditional and widely used enclosure. As it is nearly impervious, an extremely small amount of air is allowed in over time, which actually does help the wine while it matures in the bottle. The material is also recyclable. Disadvantages are mostly due to storage and cleanliness. Any temperature variation can allow air into the bottle which could oxidize the wine. Also, chemicals introduced to the cork in the orchards and in production can cause the funky "corked" tastes.
- Screwcap. Also known as a "Stelvin cap", this enclosure is mainly used on New Zealand and Australian wines, though it is becoming globally prevelant. Its small ventilation system allows the least amount of air, but just enough to help wine maturity. One disadvantage: many consumers have had a hard time accepting it, and think it is only used on cheap wines- untrue.
- Synthetic. Plastic compounds shaped like a wine cork. Many disadvantages: they have the most oxidation problems, can impart chemical flavors to the wine, are non biodegradable, and can be hard to open.
- Vino-Lok. This is a glass top with an O-ring which prevents oxidization, similar to a screw cap. It can be easily reapplied after opening if all of the wine is not consumed. Its biggest disadvantage is its cost- .70 USD/each plus manual bottling.
- Zork. This enclosure seals like a screw cap and pops like a cork. Just untwist three times and pop. It contains an aluminum ventilation system similar to a screw cap which allows a small amount of oxygen. Again, this may be a bit hard to accept by cork traditionalists. Also working on recycling, as it is made of polyeurathane.
- Crown Cap. This is used to seal sparkling wines during fermentation and is usually replaced with a cork, though some wineries, like Domaine Chandon, stay with the cap. They are very easy to open and free from cork taint. They do take some of the mysticism from the opening process.
All this considered, my favorite enclosure is the screwcap. It is proven to be the most reliable enclosure, the easiest to open and reuse, and best for the environment. One of the worlds best producer of chardonnay, Leeuwin Estate, is at the forefront of change. They not only changed from cork to screwcap, but also spent thousands to change their entire reserve cellar, comprised of award winning past vintages. Through research, study, and consensus tasting, they found the screwcap to keep the wine freshest over time, offering ageability. I agree with Leeuwin, and have found many of the wines I have tasted under screwcap to be more fresh and lively.
(Image courtesy of flickr)