One of the bigger debates about wine drinking has to do with whether or not it’s really important to let a wine breathe before you drink it. Even among wine drinkers there’s a lot of disagreement about whether it’s important, whether all types of wines should breathe or how long a bottle needs to breathe.
So here’s the scoop on giving that bottle a few minutes before you enjoy it. The idea of letting air into the bottle – especially for red wines and ports is that letting a little oxygen into the wine will open up the flavors and make it more robust. On the other hand, left to the air for too long, some wine pros will tell you that flavors begin to fade. Others will tell you not to worry about letting it breathe in the bottle, but you should air it by swirling it in your glass. And we know that aged wines (more than 15 years old) are considered fragile and do better with a shorter breathing time.
The average time a bottle of wine should breathe is about 30 minutes. But the best way for you to decide what amount of time you prefer is your own trial and error experiment. Open a few bottles of your favorite wine and sample them without breathing, at about the 10 minute mark and then at 30 minutes. See what you notice about subtle changes in the flavor and you can decide what your decant time is going to be.
The other reason for decanting is less subtle. Fermentation causes sediments – especially in older red wines and ports. Color pigments and tannins will bond inside the bottle and as you pour, that sediment will end up in your glass. This is what can give wine a cloudy appearance as well as leaving a bitter taste or even a gritty residue. Sediment isn’t harmful, it just isn’t pleasant.
Decanting helps separate the sediment from the wine.

Here’s how it’s done:

1) Let the bottle stand upright for 24 hours.
2) Open your bottle and wipe off the neck of the bottle (inside and outside)
3) Pour slowly into a decanter or pitcher without stopping.
4) As you reach the midway point of the bottle pour even more slowly
5) Stop when you see the first sign of sediment in the neck of the bottle.
6) Discard that last ounce of sediment-filled wine.

Remember that pouring the wine into a decanter will help it breathe more quickly so you’ll want to take that into account as you estimate the amount of time you want the wine exposed to air.
Decanting is part art and part science. But mostly it’s just a matter of personal taste. Experiment and have fun finding that perfect prep for your favorite flavor!