- The serving decanter is the modern incarnation of the decanters the Romans used over 2,000 years ago. A simple glass vessel, it can be filled with wine poured from a barrel, carboy, box or tap and provide a way to serve a specific measure of wine without exposing the contents of the larger vessel to oxygen. Decanters known as carafes are often used in restaurants to serve different amounts of wine, usually 50 ml and 75 ml, poured from a tap at the bar.
- Older wines, and those made using more traditional wine-making techniques, often build up gritty sediment over time. Decanting is traditionally used to prevent this sediment from being poured into somebody's glass. Decanters designed to separate wine from sediment normally have a large opening that makes pouring wine into them easier. Once a bottle has been opened, the majority of the wine is poured into the decanter and a little remains in the bottle, containing the sediment that has sunk to the bottom of the bottle.
- Oxygen has the power to dramatically affect how a wine tastes. Most wine enthusiasts agree that certain wines -- especially reds -- benefit from being exposed to oxygen before being consumed. Wine decanters designed to aerate wine are chosen for this purpose. They traditionally have a wide, low base that exposes the maximum surface area of wine to oxygen after it has been decanted.
- Wine decanters are often used simply because they improve the appearance of wine. Fine crystal decanters showcase the color of both red and white wine and can enhance even the most nondescript vintage. Wine decanters designed purely for appearance can vary hugely in design, and may or may not contain some of the design details inherent in decanters designed for a specific purpose.