Merlot and Cabernet Sauvignon are types of grapes that lend their names to varieties of red wine. In the United States, wines are typically named after the grape that produces them. In contrast, Europeans usually refer to wines by the location where they are grown, such as a Bordeaux wine, which is named for the famous wine-producing region of France.
Still, no matter where the vineyard is located or how the wine is made, the type of grape used is essential to determining the wine's personality. "Cabernet Sauvignon is marked by plum, currant and black cherry flavors and firm tannins," writes James Laube of Wine Spectator. This holds true whether it's bottled in the Stag's Leap District of Northern California's Napa Valley or an estate in Chile's Maipo Valley.
The soft and fruity Merlot grape is sweeter, smoother, and lower in tannins. This means it blends well with other grapes and is ready to drink at a younger age. In fact, it's the most widely planted variety in the Bordeaux region, and is a popular choice of American red wine aficionados.
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