The vast majority of white wine grapes are made in an "unoaked" style, as with pinot grigio, riesling, albariño, and grüner veltliner. Chardonnay is the obvious exception, where many of its wines -- and particularly superior cuvées -- are first barrel-fermented then aged on their lees in barrels as well. There are only a handful of other white grapes that can benefit from this chardonnay-style treatment, and sauvignon blanc is one of them.
Even though the vast majority of sauvignon blancs are unoaked, this grape comes in second behind chardonnay in frequency of barrel use -- a legacy of its history in the barrel-obsessed Bordeaux region.
This estate wine from a large Central Coast winery in California makes an interesting example. First, the wine sees what's known in the trade as "partial barrel" treatment, with 30% of the wine being fermented and aged in barrels, and the remainder matured in stainless steel tanks. What is more unusual, though, is that the barrels used are made from two different types of wood. Some are traditional French oak barrels, all of which are "neutral," meaning that they've been used to mature wine for a few years and no longer impart an oaky flavor. The rest of the barrels are made of acacia, with both new and neutral acacia barrels in the mix.
Acacia is being experimented with throughout the wine world because, like oak, its grain is fine enough to make a watertight vessel yet elastic enough to be bent into a round shape. In winemaking, acacia barrels enrich wine texture as effectively as oak does, but the flavor profile they impart is dramatically different. Where oak flavors echo warm-dessert elements, like vanilla, nutmeg, or toasted almond, acacia is brighter and more subtle, imparting delicate flavors in the herbal and floral families. That's why we are seeing more and more experiments with acacia barrel regimes like this one; winemakers can use it to add a luxurious mouthfeel to a white wine without adding an intrusive oaky taste.
Here, we find the distinctive citrus and tropical flavors of sauvignon blanc, like lime, kiwi, and papaya -- a flavor profile that seems decidedly unoaked. But we can also discern a touch of decadent creaminess on the palate, one that requires time in barrels and can't be achieved in steel tanks alone.