And the answer is: Decant! No, it’s not that easy, but it’s close. Here are some thoughts on how to decide.
The most obvious reason to decant is to separate the wine from any sediment that has formed in the bottle. Sediment won’t hurt you, but it doesn’t look pretty in your glass and can sometimes taste bitter or astringent. Before winemakers knew how to clarify their wines properly, decanting was the norm. Now, it is rare for inexpensive, everyday table wines to throw any sediment. A common culprit is vintage port – it’s bottled early in its evolution, so it will often throw a heavy deposit. Other aged red wines will too, because some of the solids have precipitated out as part of the maturation process. We can save “which wines are ageworthy” for another posting, but if it’s in a box, a jug or if it’s colored pink, drink it up and don’t worry about decanting it.
The other main reason to decant is to aerate the wine and encourage the development of the wine’s bouquet. Don’t laugh because I used the term bouquet – it’s been used since the first half of the 19th century to describe the perfume of the wine. My dad likes to bust my chops about the difference between aroma and bouquet and while many authorities may have a differing opinion about when a wine’s smell stops being an aroma and becomes a bouquet, it boils down to this: aroma is the simple smell of the grape and bouquet refers to the more complex compounds which evolve from fermentation and bottle aging. So there, pops.
Karen MacNeil, author of The Wine Bible advocates decanting very tannic wines (think Barolo, Bordeaux, some Rhônes) and notes that it can be detrimental for more delicate wines (think Chianti or Pinot Noir). Noted oenologist Émile Peynaud on the other hand argues that the action of oxygen dissolved in a sound wine when it’s ready to be served is detrimental – the aroma instead of being pronounced will be diffused and less marked. He suggests only decanting when there’s sediment and just before serving. Keep in mind that if you are following the steps from “swirl it, sniff it and slurp it down”, you’re aerating the wine as you agitate it in your glass.
Some folks claim that decanting softens the tannins in wine and experts have contested that decanting merely alters the perception of sulfites and other chemical compounds through oxidation, therefore making the wine seem easier to drink. One thing we don’t have to argue about is the fact that a decanter looks darn pretty on your table (especially when it’s full of wine) and will get everyone excited for the meal.