It’s a beautiful thing to witness, a sommelier expertly pouring a bottle of deep red wine into an elegant glass decanter. Decanting is widely practiced in fine dining, in tasting rooms, and among oenophiles in living rooms everywhere. But what exactly does it do? Does it really enhance the experience of drinking wine, or is it primarily for show?

While it is undoubtedly an impressive technique to witness, decanting absolutely heightens the taste of the wine as well. Decanting is primarily done for two reasons: to remove sediment from wine and to aerate it. Older reds and ports are likely to contain sediment, which muddies the wine and imparts a gritty texture if poured directly into a glass. To decant to remove sediment, leave a bottle of wine upright for at least a day before serving to let the sediment settle. Then, when you’re ready, pour very slowly, with a flashlight or candle underneath, until you see the sediment enter the neck, then stop.

Reds that are less than fifteen years old likely won’t contain sediment, and whites rarely do, but they will still benefit from aeration. The initial exposure of wine to oxygen intensifies the wine’s flavor so that you can best taste all the notes described in the tasting menu (the same reason you swirl wine around in your glass before drinking). Newer reds and whites can be decanted up to an hour before serving. There are lots of special gadgets for decanting these days, but if you’re just doing it to aerate the wine, there’s no need to get fancy—just pouring into any clean container will make your wine sing.