Napa Valley luxury winemaker Silver Oak is adding the first new varietal to its portfolio in a half-century: Sauvignon Blanc. The new varietal ($40 a 750-ml.) is sourced from four estate vineyards across Napa Valley and Sonoma County. Silver Oak Sauvignon Blanc first debuted online, with broader on-premise distribution following this summer. The Silver Oak brand also produces Napa Valley Cabernet Sauvignon ($200) and Alexander Valley Cabernet Sauvignon ($100). The new release is available nationwide. For more information, visit Silveroak.com