The North Bay is a bottomless fount of subcultures, from carburetor enthusiasts to alpaca farmers to home bookbinding groups—and now, fermenters, as evidenced by last year's runaway success of the Freestone Fermentation Festival. A celebration of all things curdled, pickled, leavened and brewed, the festival attracted hundreds jockeying for the subtle perfection of that perfectly tangy flavor at last year's inaugural gathering, and another Sonoma County subculture was officially born.

Wine being a product of fermentation that's already sufficiently celebrated around these parts, the Freestone Fest focuses on nonalcoholic fermentation. "There's so much more to it," says Michael Stusser, festival founder. "Fermentation was really at the foundation of the food preservation system before refrigeration came along. It's definitely an art."

On the grounds of the Salmon Creek School—about halfway between Freestone proper and Occidental—the festival's the spot to try locally made breads, cheese, kimchi, pickles and sauerkraut. On the rise in Sonoma County is kombucha, a brewed tea given a certain amount of zip from a white, foamy "mother" cake, and if you've never tried nato, a Japanese soybean dish, you're in for a surprise. Admits Stusser: "It is an acquired taste dish."

Throughout the day, speakers will enlighten on sugars and microorganisms, while how-to classes on kimchi, sauerkraut and kombucha are sure to turn your kitchen into a science lab for the next several weeks. Music comes courtesy of the Mighty Chiplings, Jennifer Tucker, the Dream Farmers, the Hubbub Club and more, and, for the exhausted fermenter, there are even enzyme foot baths.

The real fun, naturally, is talking with the fermenters themselves about their process. Exhibitors include Redwood Hill Farm, Grindstone Bakery, LonjeviTea Kombucha, Cultured Pickle Shop, Alexander Valley Gourmet and many, many more, including Freestone's own Wild Flour Bread and Osmosis Day Spa. It's all happening on Saturday, May 15, at Salmon Creek School, 1935 Bohemian Hwy., two miles north of Freestone. Noon-5pm. Mention the Bohemian for special $15 ticket price at the door.www.freestonefermentationfestival.com.

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