Have you heard about “decanting,” but may not know what it is (or its purpose)? Decanting a wine involves transferring it from a wine bottle into another receptacle (the decanter) before serving. Traditionally, there are two reasons to decant a wine; (1), to separate the wine from sediment that has formed at the bottom of the bottle, and (2), to “open up” the wine so that it better releases its aromas and flavors.
Most commercial wines go through a filtering process prior to bottling that effectively removes any sediment, and thus, these wines rarely need decanting to remove sediment, especially if they are consumed within a few years of going on the market. Older red wines may well produce sediment as they age because the color pigments and tannins in these reds begin bonding together and “fall out” of solution, producing bottle sediment. For these older red wines, if you stir up the sediment when pouring the wine into glasses, you will be drinking cloudy wine that will most likely have a bitter flavor and a gritty texture, which is something you want to avoid. Hence, decanting.
Some argue that it is no longer necessary to decant a wine in order to release its aromas and flavors because there are now wine aerators on the market that can be used, but others believe that decanting is more effective. On this question, I think it comes down to personal preference!