The ever expansive Orville Magoon, owner of California's Guenoc Winery, paid a recent visit to the Milwaukee area. The additional aeration, he believes, helps freshen things up. He also noted that improper storage of wine after it is bottled can be disastrous. Wines left in a sunny store window or a warm closet may become oxidized. It is similar to what happens, although more quickly, to an open bottle of wine that sits around for a few days.
Red wines become reddish-brown, white wines darken.
The wine tastes flat and may even take on a sharp, vinegar-like quality. He spoke by phone just as he was heading out to check on one of their chardonnay vineyards. The cooked or raisiny quality indicates the wine has become maderized. The term is used because the wine's aroma and flavor are reminiscent of Madeira. Some people like the taste, but generally speaking, it is not considered a plus.