Talk:Gordon Ramsay vs Julia Child/Rap Meanings/@comment-1681197-20160527041913

To "open up" refers to more than just uncorking the bottle. Reds, especially "fine reds" such as Cabernet Sauvignon, most Red Zinfandel, Bordeaux, etc. need to be decanted and allowed to breathe so that the tannins soften and the taste becomes less harsh. Wines decanted in such a way are referred to as "opened", whereas a "closed" wine would be one that is poured straight from the bottle to the glass, not allowing any time for aeration.

source: http://www.totalwine.com/wine-guide/decanting-wine