Sparging

sparging, a wine means stripping it of oxygen or carbon dioxide by purging it with fine bubbles of an inert gas, usually nitrogen. The technique is not widely used because it removes not only oxygen but also significant amounts of volatile flavour compounds. A tank or bottle may also be sparged with an inert gas. Sparging can also refer to the injection of carbon dioxide into the wine, with or without nitrogen, to increase the concentration of carbon dioxide in the wine.