Wine decanting is a process by which sediment - solid residue that settles to the bottom of a bottle over years of aging -- are filtered out by pouring the wine from one vessel into another. In the world of wine experts, it is debatable whether it is necessary to decant all wines; however, it is inarguable that the wine decanter adds elegance to any table. Decanting processes vary with wine types, and it is usually done before serving the wine.
The use of wine decanting and decanters had its place throughout history as a dinner table tradition. It can be dated back to the Ancient Romans, who used glass wine decanters. When glass-making diminished with the fall of the Roman Empire, decanters were still used, but were commonly made of silver, bronze, and earthenware. During the Renaissance, glass decanters were reintroduced. Much later, the British added decorative stoppers to the decanters. Today, the process of wine decanting and the look and function of decanters is hardly different than what it was centuries ago.
The decanting process is simple: pour wine from one vessel into another. In some cases, though, it does require knowledge of the wine in order to apply particular technique. Some wine experts argue that certain wines do not need decanting, such as young wines, which have no sediment. Older wines contain more sediment with age, and the sediment can add an unpleasant, grainy texture to the wine, interfering with the drinker's enjoyment.
The wine decanter isn't just pleasing to the eye, but is intended to improve the quality and taste of the wine. The separation from sediments is not the only function of decanting, as aerating the wine is important as well -- at least, if the wine is young. The process of aeration mixes the wine with air, "opening up" the wine and allowing the various flavors and aromas to fully express themselves. Aeration is aided by having more surface area for the wine to interact with the oxygen in the air. A decanter allows much more surface area than a bottle of wine. If it is an older wine, too much aeration can ruin the taste. If the decanter is used as an aesthetic addition to the table, there is a wide range of styles, shapes, and sizes. Often, the vessel is clear glass to allow the wine to be admired at the table. Some also come with decorative stoppers, which rest on the top of the wine-filled decanter to prevent over-aeration.
Experts recommend that younger wines be poured into the decanter and left to "breathe" about thirty minutes before serving. This way, they are aerated enough to improve their taste. Older wines require a very slow pouring into the decanter, to ensure that the sediments remain in the wine bottle. Also, the tip of the wine bottle should stay close, or even touching, the top of the decanter during the pour, since too much aerating of an older wine is advised against, in order to protect its flavor. Older wines should be poured into the decanter immediately before serving. It is widely believed by wine experts that decanting is only effective for red wines; however, there are still some who testify that the taste of a white wine can be improved in this way, too.