The so-called millennial wine consumer, the most recent age group being tracked as a force in the U.S. wine market, seems fascinated with wines that just a few years ago were of no interest to baby boomer wine buyers.

Just a decade ago, chardonnay was wine consumers' overwhelming choice for a white wine and cabernet sauvignon was clearly tops as a red.

Chardonnay and cabernet remain popular, but neither is as interesting with new consumers as they were with prior wine-buying demographic groups. In the last few years, a wide range of new grapes and wines seems to be getting a lot of attention from buyers looking for distinctiveness.

The shift in wine choices has included numerous "new" wine grapes, many of which are so obscure that only a handful of people know much about them. Indeed, there are so many grapes now being turned into table wines around the world that books have been written to explain them.

Of the literally two dozen or more wines from relatively obscure grapes, the majority are grape varieties that have flourished around the world for decades if not centuries, and recently have been made with more style and verve than in the past, partly as a result of better grape-growing and wine-making techniques.

One of the most interesting is the northwestern Spain white-wine grape Albari? (Alvarinho in Portugal), which has an aroma not unlike the spice of Gewurztraminer, but whose fascinating floral/tropical notes are more like fresh peaches. Some versions of this wine are made slightly sweet, but a dry classic is the 2012 Tangent Albari? from Edna Valley ($17).

Another fascinating wine comes from Gruner Veltliner, a steely Austrian grape that makes some stellar white wines in its homeland. Among the small number of U.S wineries making it into wine are Dr. Konstantin Frank in New York, Galen Glen Winery in Pennsylvania, and Zocker in California. All are $20 or less.

One fascinating red wine that flies under the radar is Gamay Noir, the same grape that's used to make Beaujolais. It also makes a more serious red wine, well proven by Amity, WillaKenzie, and Brickhouse, all in Oregon, and by Chateau Grand Travers in Michigan.

Tannat, a red wine grape that can make some strongly tannic red wines in France, has been tested in California (notably in the fine Silvaspoons Vineyard in Lodi). Now an adventurous importer, Global Vineyard in Berkeley, is importing an attractive Tannat from Uruguay called Marichal ($15). It's nowhere near as tannic as its European counterpart.

Argentina's entry here is called Torrontes, a spicy white wine that can smell a lot like pineapple and is occasionally sweet. One of the best is from Finca El Origen, a premium brand of Santa Carolina ($10).

Perhaps the most passionate "orphan grape variety" fan of them all is Mendocino County winemaker Greg Graziano, whose four brands (Enotria, Monte Volpe, Saint Gregory, and Graziano) offer wines from grapes like Cortese, Arneis, Muscat, Barbera, Charbono, Dolcetto, Tocai Friulano, Chenin Blanc, Aglianico, and others.

Graziano, an excellent and courageous winemaker, believes the world has plenty of chardonnay and cabernet, and he has gone out of his way to dedicate his various brands to wines from worthy if obscure grapes. Details at www.grazianofamilyofwines.com.

Wine of the Week: 2010 Fairview Pinotage Viognier, Coastal Region ($17) — The Pinotage variety is most widely grown in South Africa, where this wine comes from. Its faintly earthy, Rh?e-like aroma is fruit-driven and appealing. But the variety is a crossing of pinot noir and cinsault, and the former grape gives this wine a softer tannin structure. A fascinating look at yet another "new" variety.

Sonoma County resident Dan Berger publishes "Vintage Experiences," a weekly wine newsletter. Write to him at winenut@gmail.com.