In recent posts we learned that cork comes from the bark of the Cork Oak and that the foil capsule covering the cork was originally put into place to protect the cork from insects and rodents. So you might wonder is all this necessary today? Aren't there viable alternatives to using natural cork as a means of sealing a bottle of wine?
The advantages of natural cork include its ability to compress and expand (it's malleability), its proven long-term ability keep a bottle sealed, its renew-ability (because, after all, corks do grow on trees!), and a cork does allow the bottle to 'breathe' and improve (sometimes) with age.
On the downside, natural cork may be a renewable resource, but it is a limited resource as forests of Cork Oak continue to shrink around the world. Additionally, cork is relatively expensive since the bark must be manually shaved off the trees and processed to make corks. Another downside to cork is that it is formed in nature and, therefore, its quality is variable. This variability leads to natural corks having different degrees of 'breathe-ability." And finally, with a natural cork, there is a chance that a bottle of wine will become tainted by the cork (subject of a future blog).
So, what additional ways are there of sealing a wine bottle that do not involve natural cork? Well the first alternative actually involves nature cork. To deal with cost and variability, 'technical corks' are produced by grinding up the scraps of cork bark that remain after corks are punched out of the bark, and this cork 'dust' is glued together, somewhat like particle board is produced. These technical or composite corks are less expensive to produce and more consistent in quality.
Another alternative to natural cork is synthetic cork. These 'corks' are made with polyethylene (plastic). These are cheaper to produce, do not use a limited natural resource, and do not lead to possible cork taint. Due to the fact that they don’t dry out, plastic corks are easier to take out the bottle and they won’t crumble into the wine. At the same time however, they are often harder to put back into the bottle because they are not as malleable as natural cork. And, because they are plastic, they are recyclable! Finally, synthetic corks are not for serious wine collectors who purchase wines for aging. This is because they do not allow the wine to 'breathe' while in the bottle.
The other alternative to natural cork is the hotly debated twist-off cap. We'll get into this cork alternative next time. Cheers!
