JUST WHEN you think you've sorted through all the confusing wine terms to be found on back labels, here comes "wild yeast" — sometimes referred to as "native" or "indigenous" yeast. The terms conjure up visions of little yeast cells, in colorful tribal garb, dancing to some primeval rhythms. Which, it turns out, isn't too far off the mark.

The great majority of contemporary wines are inoculated with purchased yeasts, used by winemakers to induce specific aromas and flavors into the wines, and to ensure that fermentations are trouble-free and complete.

This is a fairly recent innovation. Throughout history, wines have been made simply by tossing the grapes into a vat or tank or barrel, and letting the natural yeasts already present get to work.

It's a somewhat riskier process. Stuck fermentations, exotic aromas and bacterial infections can occur if the wine is not carefully tended. But being the adventurers they are, more and more Washington winemakers are returning to these old ways.

What flavors or benefits might these native yeasts bring? Brennon Leighton, Efesté winemaker until recently, believes they help the wines "express themselves in an authentic and focused way. The mouth feel is congruent, and the tannins more integrated. More density without the wine coming across hard or over-extracted."

Chris Peterson, a partner in a new project called Avennia, is also a wild-yeast evangelist. He agrees it enhances the mouth feel of the wines. "Since the fermentation doesn't start immediately," he explains, "the grapes are cold-soaked (left in their own juices) for a few days, adding skin contact time for flavor and color."

My own tastings of both white and red wines naturally fermented seem to confirm that wild yeasts produce more floral aromas, more complex and delicate flavors, and a refreshing, textural mouth feel. Here are some current releases to try:

Efesté 2010 Lola Chardonnay; $30. Concentrated and complex, with hints of floral, citrus flesh and rind, gooseberry and chamomile.

Efesté 2009 Final-Final Cabernet-Syrah; $27. Floral top notes give way to firm, dark cassis and blackberry fruit, with light notes of herb, anise and earth.

Efesté 2009 Big Papa Cabernet Sauvignon; $49. A chewy cabernet, grainy and dense with cassis, coffee and cacao. Threads of smoke and a base of gravel add length.

Avennia 2011 Oliane Sauvignon Blanc; $25. A tart, tightly focused wine with laserlike precision and a wealth of mineral and lemon flavors.

Avennia 2010 Parapine Syrah; $35. Complex and even delicate, despite its 15 percent alcohol, this has black cherry, cola and earth, with a drying finish.

Avennia 2010 Arnaut Syrah; $45. Sleek and focused, this offers raspberry and black cherry fruit, with excellent focus and length.

Gorman 2011 The Big Sissy Chardonnay; $35. Scents and flavors are exceptionally detailed, running from fresh clover into tree fruits, yeast and lots of pretty toast.

Paul Gregutt's blog is www.paulgregutt.com. Email: paulgwine@me.com.