We wrapped up the evening back in Sonoma Valley at St. Francis's nearly-finished, state of the art winery. Thanks to a cool summer so far, it looks like a late harvest will give them time to settle in before crush starts. Winemaker Tom Mackey (above, at left) set up a wonderfully instructive comparison of the distinctions between cooperages. We tried five samples of St. Francis' 1998 Sonoma County "Old Vines" Zinfandel, aged for 10 to 12 months in nearly identical barrels made with American white oak from Missouri, Kentucky and the Ozarks, 59- to 60-gallon capacity, air-dried 18 to 30 months, with medium toast levels.

The characteristics imparted to the wines from the five different barrel-makers was amazing. Demptos added distinct sweetness, diffused sweet vanilla and almond flavors; Radoux, flavors of coconut, toasted bread, and a mild sweetness; Mendocino Cooperage, vanilla, spice and a potpourri of flavors; Lafitte, delicate flavors and smoother textures; and Stavin, carmelized chocolate, roasted coffee and vanilla bean flavors.