At one time there was no question about how best to close a wine bottle; you simply put a cork in it. Today, winemakers have more choices. Besides natural cork, the options include synthetic stopper, glass stopper and screw cap, to name the most common closures. Deciding which one is best to preserve the wine in the bottle involves such considerations as type of wine, cost of the wine and packaging, and perhaps, most importantly, the image presented to you, the consumer.
Where the bottle of wine is placed in a store or on a wine list may influence the sale, but even more important is the way the bottle looks on the shelf, the image conveyed by the winery that says, “Look no further, this is the quality wine you’re looking for.”
A big part of that image is at the top of the bottle. A savvy consumer will know by looking at the bottle that the smooth capsule dressing most of the time hides a natural cork.
At first glance, it’s easy to tell that most screw caps look like screw caps, even though recent attempts have been made to fashion the cap and capsule unit to look more like a traditional wine bottle capsule.
All bottle closures have their advantages and disadvantages, but two closures are by far the most popular choices and the ones generating the most chatter in the wine community. Natural cork, the stopper fashioned from the bark of a cork oak tree, is the traditional closure and, according to its legion of advocates, is the only choice. A more recent arrival on the wine scene, and one that is slowly growing in popularity among the wine trade and the buying public, is the screw cap, a closure more commonly seen on soft drinks and bottled water than wine.
Synthetic stoppers (so-called because they are not made of cork) have been around a bit longer than screw caps but these “plastic” closures have been slow to catch on with wineries or wine consumers. According to a recent survey by Wine Intelligence, a UK-based company that supports wine businesses worldwide, the growing legion of wine drinkers in China prefers synthetic closures over screw caps.
Cork oaks are found mainly in Portugal and Spain, with smaller forests in Sardinia and Northern Africa. The bark of a cork oak is harvested every nine years, making natural cork a 100 percent renewable, watertight and sustainable natural resource, an important advantage as the wine industry goes forward with a strong emphasis on sustainability. Portugal and Spain closely regulate the growth and harvest of their trees, to assure a continuous supply of corks for wine.
The major disadvantage of natural cork is that it is susceptible to “cork taint,” (commonly called TCA), caused by the presence of a mold that permeates the cork, giving the wine a musty or off smell and taste.
Recently, the cork industry has made gains at eliminating Trichloroanisole, or TCA, resulting in fewer corked wines today than a few years ago.
Amorim, the world’s largest cork producer, claims that it will eliminate cork taint by 2020. Nomacorc, another major producer of wine corks, recently released their Green Line of corks, made from sustainable sugarcane-based raw materials. Screw cap manufacturers, like the well-known Stelvin, claim that screw caps do not have a problem with TCA contamination and that they are both airtight and watertight.