Wine Industry Resources
8.25.2008
Alternative Wine Closures
Traditional cork bottle stoppers have been in use by the wine industry since the 1600s. The downside of cork is a condition known as "cork taint", which, depending on who you talk to, affects anywhere between 0.5-10% of wine bottles sealed with the oak bark. It's the result of a chemical called TCA that some corks impart into the wine. The result of obvious cork taint is a smelly, damp, or moldy aroma or taste. In smaller concentrations, TCA may not be overtly noticeable, instead subduing a wine's natural flavors and leading the drinker to mistakenly feel a wine is uninspired or a little "off" when in fact they're tasting a tainted bottle.
To avoid this, many winemakers have turned to alternative methods of closing their bottles, including artificial corks, screwcaps, glass plugs, and even crown caps. However, each of these methods has a different affect on the ability of a wine to age properly relative to traditional cork. Combine this with the different ways in which wine consumers in various markets around the world perceive these different closures and each winemaker obviously has to choose his preferred method carefully. Let's examine some of the most common alternative closures:
Artificial Corks
Artificial, or synthetic, corks are designed to match real cork in size and shape and to be used in the same sort of bottles as real cork. They are produced by various companies using varying methods, but are all made from some form of plastic substance. While solving the problem of cork taint, these synthetic corks currently do not seal as well as traditional cork, thus letting in more oxygen. This means that with time the wine will often oxidize instead of improving with age, so it's typically recommended that one drink these wines relatively soon after purchase instead of laying them down to age for several years. As synthetic cork technology develops in the future, it's possible they may become more airtight.
Screwcaps
Certainly twisting off a screwcap is less romantic than popping a cork, but the screwcap is spreading and here to stay, and with good reason. If you are not already aware, please take note that screwcaps are not just for "cheap" wines; the makers of many premium wines are using this closure method because those winemakers believe it to be the most effective way to preserve their wine. Screwcaps actually seal considerably better than natural cork, letting in far less oxygen and obviously disallowing any risk for cork taint. They are also handy for when one wishes to reseal an open bottle. Many wines from "Down Under" are sealed with screwcaps, particularly those from New Zealand, and their use has been increasing in many parts of the world. One question still being debated is whether screwcaps are a good choice for wines that are best aged for several years. Many wine experts believe the extremely low levels of oxygen permeation are not ideal for long term aging.
Glass Stoppers
A relatively new product known as "Vino-Seal" has hit the market, consisting of a glass plug that fits in the bottle's neck and over the lip. There's a small rubber ring that seals the stopper against the top lip of the bottle forming an airtight seal. The first time we saw the Vino-Seal here at The International Wine of the Month Club was on the 2006 Zantho Zweigelt from Austria that we featured in March 2008. We were all intrigued by the very classy looking device, and have learned that, like screwcaps, these seals allow for very little oxygen permeation compared to natural cork, although they are more expensive for the wineries.
Crown Caps
Crown caps are the same little metal caps found on the tops of beer bottles. Winemakers have actually been using them in sparkling wine production for a very long time, using them to seal the bottles prior to disgorgement, after which time they receive their cork finish. Recently some wineries have begun topping their finished sparkling wines with crown caps to avoid the risk of cork taint or even to lend a less "uptight" appearance to the bottle so that it appeals more to customers from non-traditional demographics.
Despite all of these alternative closures, natural cork is still the most popular method of sealing wine bottles worldwide. Additionally, cork producers have been very active in recent years to develop methods of production that prevent TCA contamination of their corks, and many experts feel the cork taint problem may soon be a thing of the past. So, natural cork looks well-positioned to remain the closure of choice for most winemakers for the foreseeable future.
To avoid this, many winemakers have turned to alternative methods of closing their bottles, including artificial corks, screwcaps, glass plugs, and even crown caps. However, each of these methods has a different affect on the ability of a wine to age properly relative to traditional cork. Combine this with the different ways in which wine consumers in various markets around the world perceive these different closures and each winemaker obviously has to choose his preferred method carefully. Let's examine some of the most common alternative closures:
Artificial Corks
Artificial, or synthetic, corks are designed to match real cork in size and shape and to be used in the same sort of bottles as real cork. They are produced by various companies using varying methods, but are all made from some form of plastic substance. While solving the problem of cork taint, these synthetic corks currently do not seal as well as traditional cork, thus letting in more oxygen. This means that with time the wine will often oxidize instead of improving with age, so it's typically recommended that one drink these wines relatively soon after purchase instead of laying them down to age for several years. As synthetic cork technology develops in the future, it's possible they may become more airtight.
Screwcaps
Certainly twisting off a screwcap is less romantic than popping a cork, but the screwcap is spreading and here to stay, and with good reason. If you are not already aware, please take note that screwcaps are not just for "cheap" wines; the makers of many premium wines are using this closure method because those winemakers believe it to be the most effective way to preserve their wine. Screwcaps actually seal considerably better than natural cork, letting in far less oxygen and obviously disallowing any risk for cork taint. They are also handy for when one wishes to reseal an open bottle. Many wines from "Down Under" are sealed with screwcaps, particularly those from New Zealand, and their use has been increasing in many parts of the world. One question still being debated is whether screwcaps are a good choice for wines that are best aged for several years. Many wine experts believe the extremely low levels of oxygen permeation are not ideal for long term aging.
Glass Stoppers
A relatively new product known as "Vino-Seal" has hit the market, consisting of a glass plug that fits in the bottle's neck and over the lip. There's a small rubber ring that seals the stopper against the top lip of the bottle forming an airtight seal. The first time we saw the Vino-Seal here at The International Wine of the Month Club was on the 2006 Zantho Zweigelt from Austria that we featured in March 2008. We were all intrigued by the very classy looking device, and have learned that, like screwcaps, these seals allow for very little oxygen permeation compared to natural cork, although they are more expensive for the wineries.
Crown Caps
Crown caps are the same little metal caps found on the tops of beer bottles. Winemakers have actually been using them in sparkling wine production for a very long time, using them to seal the bottles prior to disgorgement, after which time they receive their cork finish. Recently some wineries have begun topping their finished sparkling wines with crown caps to avoid the risk of cork taint or even to lend a less "uptight" appearance to the bottle so that it appeals more to customers from non-traditional demographics.
Despite all of these alternative closures, natural cork is still the most popular method of sealing wine bottles worldwide. Additionally, cork producers have been very active in recent years to develop methods of production that prevent TCA contamination of their corks, and many experts feel the cork taint problem may soon be a thing of the past. So, natural cork looks well-positioned to remain the closure of choice for most winemakers for the foreseeable future.
