Can a wine be called Cabernet Sauvignon if it contains other grapes?

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Dear Dr. Vinny,
Can a wine be called Cabernet Sauvignon if it contains other grapes?
—Richard, Aiken, S.C.
Dear Richard,
That depends on where the wine is made, but every region has laws that dictate how much of a specific grape a wine must contain for the wine to be labeled as that grape. In the United States, a wine labeled as Cabernet Sauvignon must be made from at least 75 percent Cabernet Sauvignon grapes. In Australia and the European Union, that minimum is 85 percent.
Some winemakers take advantage of this flexibility to help maintain a house style, offset vintage variation or augment structure, color or aromatics. Other winemakers like to make wines that are 100 percent expressions of a single grape. If you don’t see a grape listed on a label of a wine made in a New World region, that usually means the wine is a blend of grapes; in the Old World, appellation names are more prominently used to indicate the style and composition of the blend, and you’ll have to do a little more research to determine which grapes are included.
—Dr. Vinny