A spongy material which comes from the bark of the Cork Tree, cork is what has traditionally been used to seal wine bottles. A limited number of cork trees have produced a shortage of cork, whereby man-made materials are now being increasingly used to make and replace cork. Sadly, we may be looking at the end of cork as we know it.
Corks seem to have been around since the first wine, and there is evidence of 5th century Greeks using corks, followed by the Romans whose corks were sealed with pitch. By medieval times, corks were replaced by twists of cloth or leather, and sometimes with sealing wax.
The ability for cork to totally seal off wine depends on its having a snug fit into the bottle, and because of the properties of cork, the bottle’s opening must be uniform in diameter. It was the 17th century before the bottle making process had developed sufficiently to have uniform openings, which gave way to cork’s proliferation as a wine sealant of choice. It wasn’t until 1722 that corkscrews were developed to open wine bottles.
The benefits of cork as a sealing device for wine bottles are numerous, making it the closure of preference for almost 300 years. Cork possesses both pliability and prevention of leakage, kind of like elastic.
The bark of the Cork Oak Tree can be harvested every nine years and experiments to facilitate the growth of more Cork Oaks in North and South America, Russia and Japan have been unsuccessful. It takes 25 years to get the trees to the point where they can be harvested, and unfortunately the first cork harvested is so irregular in size and density that it is not suitable for wine bottle sealing. It’s not until the second harvest that the adequate wine cork is ready.
Over the years, the cork industry has experienced problems with quality control which have had to do with tainted corks and corks improperly sealing the bottles, which has led to the pursuit of finding an alternate sealing material for wine bottles. Cellukork is now replacing corks on many mid-range wines, despite questions that remain with regard to how these synthetic corks will hold up and even affect the wines over time. It could end up imparting flavors all its own, but for now, Cellukork is the forerunner for wine bottle stoppers.
The screw cap provides an excellent seal, however this type of cap has long been associated with inferior quality wines, and therefore may require some major revision before this type of closure is ever accepted by the public.
One thing about it...wine’s here to stay, however we are about to experience a transition from corks to...something. It’s just not clear yet what that will be.