Along with barrel-aged, you'll occasionally see this term on the back labels of expensive white wines, particularly Chardonnays. Most wines are fermented in neutral stainless steel or wooden vats, but a few high-quality white wines are made in the Burgundian style, in which the wine is fermented (and usually aged) in a small oak barrel. It's an expensive, risky, and labor-intensive process, but the reward (hopefully) is a wine of exceptional texture, complexity, fragrance, and just the right amount of oaky flavor. Red wines are rarely barrel-fermented because the juice and skins are fermented together, making the process far too arduous and impractical. See also barrel-aged.