Air. While air is our friend in the business of breathing and whipping up meringues, it can be our enemy when it comes to wine. Yet, there are many instances in which air can enhance and/or change a wine, so it’s really more a matter of managing air and harnessing it "for good."
So what happens to wine when it becomes exposed to air? Once you open a bottle, the wine inside begins to oxidize. This is a chemical process in which a wine will change and, over time, spoil. Yet, exposing wine to air can be a very good thing.
Decanting young, red wines or allowing them to "breathe" is often recommended to open up a wine. Reds that are especially tannic, such as Cabernet Sauvignon or Barolo, will most likely benefit from a little aeration. This process will soften the harsh tannins and aromas that may be a little unpleasant at first. But when to decant and what to decant?
The rule of thumb I use for decanting is basically this: if I’m opening up a fine wine before it has had a chance to mature in the bottle over a few years, I will consider decanting. Since it’s hard to know what wines will benefit from this process, I suggest you use the easiest clue I know: price. If you are paying more than $50 for your bottle, chances are it’s a wine that you will either want to cellar for a few years or consider decanting.
There are a couple of other reasons for decanting wine that don’t have to do with air. If a wine is old enough, it may throw some sediment. These are particles that separate out from the wine and may be unpleasant to consume. Decanting keeps the sediment from being poured into the glass. Pretty simple.
The other reason to decant is for a bit of drama. Having a Caesar salad made in front of you or watching cherries jubilee light up in flames is fun. Decanting wine can be a great way to make the situation more special.
I once read that something like 95 percent of the wines for purchase are intended for immediate consumption, and I think it’s true. Therefore, decanting isn’t a process most people need to worry about. Nonetheless, it’s fun to play around with, and I recommend experimenting a little bit at home. You don’t need a special decanter: any simple carafe or pitcher will do. Take the next bottle of red you plan on opening and decant it. See what happens.
Remember: it’s all about managing air.