Decanters may seem like superfluous (not to mention pricey) wine accessories that are more about pomp and ceremony than about actual utility, but decanters do in fact serve a technical purpose that can change a wine considerably and make your wine drinking experience that more enjoyable.
Besides their ability to instantly dress up your table, decanters are generally useful when you’re popping the cork on a wine that is very young and tannic, or alternatively, a wine from an older vintage that has a good amount of age on it.
Generally speaking, red wines are poured into decanters much more often than whites since reds are almost always higher in tannin. Tannins are found in the skins of grapes (as well as in the stems and seeds), and since most white wines are fermented without their skins, they end up showing very little tannin, and hence don’t usually require decanting.
Young and Tannic Wines
Young red wines from recent vintages (less than two or three years old) can be very high in tannin, depending on the grape variety, and can benefit from an hour or so of aeration in a decanter. Decanting a young wine will expose a large percentage of the wine’s surface area to oxygen, which will help soften the wine’s pronounced tannins and will help round out the wine’s overall texture or mouthfeel. Decanting a young red wine for 30-60 minutes before drinking will also help unlock the wine’s aromas and may enable the wine’s bouquet to appear more pronounced.
Red wines that are typically high in tannin and that could benefit from some time spent in a decanter include Cabernet Sauvignons or Cabernet-based Bordeaux style blends, Syrahs, Malbecs, Petite Sirahs, Zinfandels, Nebbiolo-based wines like Barolo or Barbaresco, and Sangiovese-based wines like Brunello di Montalcino.
The other scenario that calls for decanting presents itself with aged wines from older vintages. As a wine ages in the bottle it often throws sediment which precipitates to the bottom of the bottle if the wine is stored upright, or along the side of the bottle if the wine is stored laying down on its side.
Decanting an aged wine and passing it through a mesh funnel or filter that gets placed at the opening of the decanter can help separate the gritty sediment from the wine so that it doesn’t end up in your glass. Sommeliers at formal restaurants often place a small candle under the bottle while they pour an aged wine into a decanter to illuminate the glass bottle and discern where exactly the sediment lies in the bottle, making sure it doesn’t make its way into the decanter. A mesh funnel or filter also does the trick.