Cork and wine are linked by more than tradition. Natural cork provides unique physical properties that are perfectly suited for preservation and development of fine wine. Cork’s intricate cell structure, joined together like minute “honeycombs,” creates a material that is compressible, resilient and impervious. The physical properties of cork cannot be duplicated by man-made materials.
Studies comparing various wine closures show that bottles finished with cork stoppers offer the best opportunity for beneficial aging. Plastic stoppers are prone to premature aging as the synthetic oxygen barrier deteriorates over time. Wines bottled with more “airtight” metallic closures develop a “closed-in” or “rubber-like” aroma at about 18 months.
Natural cork is unmatched in its ability to withstand vagaries of bottle shape and size. It is equally capable of adapting to environmental changes in heat, cold and moisture. This benefits the wine by protecting against early oxidation and allows the wine to gain complexity and bouquet throughout its storage life.
Comparisons of various commercial wine closures show that natural cork promotes more developed and complex flavors in wine. While partly due to physical characteristics of the closure, it is likely to be assisted by the natural flavor components of cork. These flavors – like vanillin and lactone – are the same compounds found in oak barrels used for cellar aging.
Like the wine itself, cork is an expression of hand crafted, natural qualities. Together they create an environment that allows the wine to age, develop and improve. Some would say, “to have a life of its own.”
Source: Cork Quality Council