Imagine a world without cabernet sauvignon, chardonnay, pinot noir, riesling or sauvignon blanc. Those popular grape varieties make the wines most of the world likes to drink.

Familiarity is as much a factor in their popularity as quality.

But what of other grape varieties and the wines they make? The reality is there are lesser-known grapes that make equally delicious wines that allow wine enthusiasts to broaden the palate and perhaps discover a new favorite or two.

This week Wine Talk takes a look at 10 of my favorite grape varieties that are not cabernet sauvignon, chardonnay, pinot noir, riesling or sauvignon blanc.

Assyrtiko -- A dry white from the Greek island of Santorini, assyrtiko is an everyday wine that pairs nicely with Mediterranean tapas, steamed shellfish or grilled vegetables. It's also quite refreshing as an aperitif. With outstanding richness and complexity, it's a perfect wine for those who want a white wine to be round, soft and smooth. Typical fruits notes include lemon zest, melon, tropical fruits and peach. Domaine Sigalas is a reliable producer.

Aglianico -- This tannic red grape variety thrives in the volcanic soils of Campania in southern Italy. It makes wines of exceptional complexity and character that will improve in the cellar for decades. Feudi di San Gregorio's "Serpico," made from aglianico, is one of the great red wines of the world. Aglianico also is the grape responsible for Campania's long-lived Taurasi wines.

Barbera -- High acid and low tannin make this robust red from Italy's Piedmont region one of the world's best food wines. Michele Chiarlo and Vietti are two of my favorites, and domestically the Eberle Winery in Paso Robles produces one of the finest barberas in the United States.

Furmint -- Dry furmint is a rising star in Hungary's Tokaji region, which is best known for its lavish but exquisitely balanced sweet wines. The dry white from Tokaji is quietly winning over everyone who tastes it. Excellent with grilled fish, furmint exhibits complexity and depth when it is made well. One of the best is produced by Royal Tokaji.

Gamay -- The money grape of France's Beaujolais district doesn't get the respect it deserves, because it plays second fiddle in the wider Burgundy region to pinot noir. Beaujolais from the top villages of the district could never stand up to grand cru or even premier cru red Burgundy, but it is a delicious wine nevertheless. As Thanksgiving nears, Beaujolais will come to the fore, because it's a superb match with turkey and all the trimmings. Many top producers such as Jadot and Drouhin make Beaujolais, but the unquestioned king of Beaujolais is Georges Duboeuf.

Garganega -- You could win a bet or two trying to get a fellow wine enthusiast to name the money grape in Soave, the popular white wine from Italy's Veneto region in and around the city of Verona. Though a couple of other grape varieties are permitted, Soave is made primarily from Garganega. Once upon a time Soave was thought to be too simple and plain to arouse much interest in savvy wine circles, but over the past couple of decades, through the examples set by producers such as Inama, Pieropan and Bertani, Soave has gained cachet. It's fresh and crisp, but with more body and complexity than in the days of yore, and the better Soaves have a penetrating thread of minerality that is pleasing to the palate.

Grenache -- This red grape variety is the backbone of France's southern Rhone Valley, particularly in the villages of Chateauneuf-du-Pape and Gigondas. It typically exhibits ripe red-berry character and is soft and smooth on the palate. Grenache also is widely planted in France's Languedoc region and throughout northeastern Spain, where it is called garnacha. Domestically, Bonny Doon Vineyards produces a fine grenache it calls "Clos du Gilroy."

Negroamaro -- The money grape of southern Italy's Puglia region, negroamaro produces a ripe, rich red wine that exhibits intense black-fruit aromas. When it comes to value, few red wines made anywhere are in its league. The average negroamaro retails for well under $20 a bottle but the quality can compete at a much higher level. Tormaresca and Li Veli are two top-notch producers of this little known but exceptional red wine.

Roussanne -- This grape variety from France's Rhone Valley doesn't get the recognition it deserves, because it is overshadowed by the viognier from Condrieu. Make no mistake, however, it is the finest white grape of the Rhone Valley and capable of remarkable complexity. Roussanne tends to be rich and soft, with low acidity, so smooth and easy to drink. Typical fruit aromas are pear, peach and apple, and the better roussannes exhibit nice minerality. Eric Textier is a nice one from the Rhone, and domestically Truchard in the Carneros district of the Napa Valley makes a consistently fine roussanne.

Verdejo -- This high-acid white from Rueda in north central Spain is the quintessential white to serve with grilled fish or steamed clams or cockles. It can be remarkably complex, exhibiting creamy richness despite having a solid acid backbone. Typical fruit aromas are stone fruits and citrus. Two top-notch producers are Jose Pariente and Oro de Castilla.

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