To keep bread fresh, the refrigerator is both the best and the worst place for storage. For fresh sourdough bread you make yourself, the last place you should store it is in the fridge, since the bread can stale quickly in the cold, slightly moist environment. In fact, according to Epicurious.com, it can stale up to "six times faster than bread on the counter." But store-bought bread that contains preservatives should be kept in the fridge; the cool environment helps prevent mold and dryness.
ANDREWS MCMEEL SYNDICATION