Does extended oak aging reduce the fruit character of a wine?

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Dear Dr. Vinny,
Does extended oak aging reduce the fruit character of a wine?
—Mike, Burnaby, British Columbia, Canada
Dear Mike,
In a way, but I think it’s more fair to say that a few years in an oak barrel increases the wine’s barrel flavors and aromas, and as those notes get louder, the wine’s fruit flavors might seem to become quieter.
Of course, it depends on the wine, and the barrel. There are such things as “neutral,” or used, barrels that don’t really impart flavor as much as help with a wine’s textural profile. The strongest, most toasty of barrels can impart flavors of vanilla, mocha, coffee, butter or caramel, and sometimes those notes can plump up a wine’s fruit flavor, too. Instead of just cherry flavors in a wine, with some barrel influence, that can turn into “chocolate-covered cherries.” Ideally, the wine’s inherent grape personality shouldn’t conflict with what the barrels are adding, but work in tandem.
—Dr. Vinny