IN CASE you haven't noticed, frozen yogurt is back—with a vengeance. If it were a religion, Jessica Gilmartin would be its preacher and Meg Lacy its top disciple. In June 2007, the 31-year-old Gilmartin and her business partner Patama Roj opened Fraiche Yogurt, a temple to all that is pure, healthy and probiotic on Emerson Street in Palo Alto. Lacy, a fit-looking Menlo Park customer who eats the shop's yogurt twice daily, is convinced that its beneficial cultures have single-handedly boosted her immunity to colds and flu this past year.

Gilmartin is so excited about her store's product I expected her to break into song at any moment. She and Roj make and pasteurize their yogurt on-site with the help of a 50-gallon custom-fabricated steel tank, which heats the milk (destroying any harmful bacteria) and then cools it down (at which point they add the healthy probiotic bacteria). The two are "licensed pasteurizers" with certifications from the U.S. Department of Agriculture.

Even with all of yogurt's health benefits (improved immune function and digestive health, plus impressive amounts of calcium), this isn't necessarily what you focus on when you enter the store. Instead, you'll drool over the display of three kinds of fresh organic yogurt (whole milk, low-fat and nonfat Greek style), three kinds of organic frozen yogurt (natural, chocolate and soy), and a riot of perfect-looking toppings, including fresh fruit, toasted coconut, four kinds of preserves and three varieties of local honey.

After tasting a swirl of "frozen natural" ("plain" is, ironically, too plain a word in yogurt-speak) topped with juicy pomegranate seeds and homemade granola, I was a quick convert. And I was no froyo virgin either—I'd visited two other local shops the day before to gauge what all the fuss was about.

At Café Aroma in Santa Clara, every one of the 10 tables was occupied by frozen-yogurt-sucking fanatics, and this on a blustery day in mid-January. A subsequent call to inquire whether the product was made from a powder or from actual fresh yogurt culture wasn't returned, but judging by the number of people scooping up the snowy goodness I don't think anybody cared. Toppings include crushed peanuts, sliced almonds, diced red grapes, pineapple, kiwi, peaches and several varieties of cereal.

To appease Los Gatans, Café Delatti opened last year. Their "natural" (read: plain) flavor froyo was even more decidedly sour (in a good way). In addition to fresh fruit toppings, Delatti offers Cap'n Crunch, cookie dough pellets, yogurt chips and mochi (a type of chewy Japanese rice cake). Yogurt flavors include blueberry, mango, vanilla and Splenda-d "no sugar added."

So whether you're seeking organic, healthful yogurt with live active cultures or just a soothing frozen treat, one thing's clear: the yogurt craze that overtook Los Angeles and New York last year has hit Silicon Valley in a big, tangy way.

3488 El Camino Real, Santa Clara

408.985.9555

Cafe Delatti

42 Elm St, Los Gatos

408.395.1050

Fraiche Yogurt

644 Emerson St, Palo Alto

650.566.0055

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