Letting a wine breathe, is essentially exposing it to air before serving to open up its aroma and flavor.
The notion that wines, particularly reds, taste better if opened some time before serving is widely held but has no basis in fact.
However, it is true that wine aeration is accelerated when the wine is decanted into another vessel or poured into a wineglass.
There is some debate about the benefits of letting wine breathe. Some believe that the practice allows young tannic red wines to soften up and develop bouquet.
Critics say breathing is oxidation that dulls the wine’s flavor and diminishes its liveliness.
Higher-quality vintage red wines and some superior whites from Burgundy. Too much aeration may cause delicate mature wines to lose much of their bouquet and flavour.
Some breathing of old wines is good as it enables the musty smells accumulated over the years of ageing in the bottle to blow away.
Innovative designers came up with a wine breathing contraption called the Air Au Vin.
One places a cap like structure with simple spring mechanism over the bottle. The spring pulls the cap body down, gently bubbling air through the wine.