Temple's Sow notes that three things converged to stimulate the boom in Napa's wine industry. First, optimism about the potential of California's soil to produce good wine, in conjunction with a rise of wealth in the 1960s. Second, the "Judgement of Paris", a well-publicized 1974 blind-tasting event where California wines beat top French vintages. Third, the rise of Robert Mondavi, "a visionary who believed in the wine-making potential of Napa."

Sow notes that California wines are sometimes dismissed as "too oaky", but says that is very misleading. In the early days, when wines from the region were low quality, oak served as a cover, giving a gloss to cheap wines like gravy does over a cheap cut of meat. But proper oaking of good wine, however, is like putting a muscle shirt on an athlete: It showcases the best features.

"Oak is usually meant to add additional complexity to bold, powerful wines by complimenting the tannins with a slight sweetness," he says.

The French, of course, use oak, too.

"French oak barrels are typically more subtle and spicy, offering textures of satin or silk and slight sweetness," says Sow. "American barrels are stronger in flavor, adding hints of vanilla or coconut, resulting in creamier and richer-textured wines."

Tastes of Napa