The SOMM Journal

February / March 2018

Issue link: http://digital.copcomm.com/i/935769

Contents of this Issue

Navigation

Page 82 of 92

82 { THE SOMM JOURNAL } FEBRUARY/MARCH 2018 { wine faults } WHEN IT COMES TO WINE STORAGE, old habits are hard to break. But Dr. Paulo Lopes, Research and Development Manager at Amorim Cork, advises that if tempera- ture and humidity are maintained at the correct levels, wine can be stored upright with no ill effects. In fact, sparkling wine should always be stored upright: a little-known fact that seems lost on many wine experts. During the course of his groundbreaking research, Lopes has seen no difference in the amount of oxygen found in wines that have been stored horizontally or vertically. Using science to debunk the myths that persist within wine culture is liberating largely because the facts can be even more compelling than the misleading maxims. In his recent presentation at the San Francisco Wine School on the reductive and oxidative nature of wine, Lopes made it abundantly clear that, after bottling, the main source of oxygen in wine comes from the cork itself. Atmospheric oxygen doesn't make its way through the cork (neither does mold, for that matter); rather, the air trapped in cork's lenticels, or pores, diffuses into the wine over a period of roughly three years. Wines bottled under cork are impressionable in their youth (they're a bit like hu - mans in this way). How a wine ages over an extended period depends largely on the amount of oxygen released by the cork during the wine's first few years in the cellar. Not surprisingly, different grades of cork contain different amounts of oxygen: A longer, higher-quality Grade A cork with fewer lenticels will release less. "Longer corks are much more homogeneous in oxygen release," said Lopes. "Also, due to the [sloping] shape of the bottle neck, the cork is less compressed and thus releases less oxygen." Corks used to seal wine bottles have a lifespan of about 25 years, after which they begin to lose elasticity and can start to let atmospheric air into the bottle along their sides. "After ten years, a cork will lose only 1–2 percent of its elasticity," said Lopes. "And if stored in contact with the wine, it will absorb about 3 millimeters of wine. " But it's the temperature and humidity of the storage space that ultimately dictate the lifespan of the cork, which initially consists of 80–90 percent air : an amount that decreases by 10–15 percent over time. Lopes explains that at temperatures below 20 degrees Celsius (68 degrees Fahrenheit) and at 50 percent humidity, the head space in a wine bottle is as moist as vapor. Above 20 degrees Celsius, temperature has a huge impact on natural cork; it loses humidity faster than it can take in moisture from the wine and will eventually dry out. In the case of sparkling wine, corks absorb both liquid and gas as they pull carbon dioxide (CO2) from the wine. The classic mushroom shape of a sparkling-wine cork is formed by its contact with CO2. BUSTER The DR. PAULO LOPES DISPELS LONG-HELD BELIEFS ABOUT CORK by Deborah Parker Wong PHOTO BY POPLASEN VIA THINKSTOCK

Articles in this issue

Archives of this issue

view archives of The SOMM Journal - February / March 2018