While some adults get the occasional pang for a childhood snack - juice boxes, fruit roll-ups, ants-on-a-log - few want to revisit their first ever source of nourishment: placenta.

But there are a select few who do.

The San Francisco Food Adventure club, founded in June 2009 by Beth Pickens, had, until March, gathered friends and friends-of-friends to participate in relatively tame "food adventures" like harvesting mussels, making croissants from the Tartine cookbook, and foraging for stinging nettles. In February, Pickens secured a placenta from a mother who had just delivered her baby, then sent out an e-mail to the club's followers on Facebook: "I got our new placenta. FAC #12 coming soon!"

Many mammals practice placentophagy, the postpartum process of eating the expelled organ that connects the developing fetus to the uterine wall. Biologists theorize it's for nourishment.

Historically, different cultures have lauded the practice of eating placenta for medicinal and spiritual purposes, from the Morrocans, who ate placenta to increase fertility, to the Jamaicans, who believed placenta-tea would protect infants from ghosts.

The waning numbers of modern-day placenta eaters tout its purported benefits in easing postpartum depression, the theory being that placenta is rich in iron and hormones, so eating it will increase postnatal energy and raise spirits.

But Pickens, 32, the managing director of two arts non-profits, isn't a new mother, but has always wanted to taste placenta. She founded the club, open to the public and free (unless the adventure is particularly costly) to encourage culinary adventuring. "We're not into shock value," she clarified as she readied the kitchen for visitors. "We're into rarefied food and experimentation."

Placentophagy fit the bill.

On a recent Sunday, with a placenta procured, she invited fellow adventurers to her apartment in the Mission. On the counter was a bowl of water chestnuts and pieces of bite-sized placenta - think sweetbreads- sitting in a soy sauce marinade. The game-plan: wrap the placenta and water chestnuts in bacon, then skewer and broil to make a twist on liver rumaki.

Some club regulars decided to skip this adventure.

"This is the most controversial," said Pickens, citing the yuck-factor. "Some people had a delusion that this is cannibalism, but it's not because nobody died."

Well, not exactly.

According to John Gosling, anatomy professor at Stanford University School of Medicine, placenta "is part of the infant, no question. Yes, it's discarded after birth," he says, "but it's still human."

So, is cannibalism illegal?

Surprisingly not, according to California penal code.

"I'd say it's closer to biting your finger nail than a Jeffrey Dahmer/Hannibal Lecter situation," says Steve Wagstaffe, San Mateo County district attorney.

Most Bay Area hospitals let mothers take home their placenta - the Lucile Packard Children's Hospital at Stanford, UCSF Medical Center, and California Pacific Medical Center all do - after signing a consent form stipulating that they will properly dispose of it.

Still, placenta-takers are in the minority. Elliott Main, chief of obstetrics at CPMC, estimates that annually, not more than three out of the 6,000 mothers who deliver at the hospital put in a request. And not all three necessarily consume it. Some families choose to plant it in the garden with a tree, thereby making a living monument to their child.

For those who want to eat it, there are a few options.

Four-star San Francisco chef Daniel Patterson of Coi spoke at the Museum of Modern Art earlier this year preparing his wife's placenta - which he did at her request - by soaking it in milk, salting it, then cooking it with pork into a Bolognese sauce, which he topped with a poached egg. He looked at it as a culinary challenge, but one that also eased his wife's postpartum pain.

One method is to "encapsulate" it (see placentabenefits.com). For $250, Traci Moren, one such San Franciscan "encapsulation specialist," will drain the placenta of blood - a human placenta weighs about six pounds, with a thick membrane enclosing a bloody sac - steam it with ginger and myrrh, slice it, dehydrate it, grind it into a powder, then encapsulate it, all at the mother's home. Mothers take the pills a few times a day for about a month.

Moren had a baby six months ago and found encapsulation more palatable than other common methods of placenta ingestion, like blending it raw into a smoothie, or cooking it into lasagna. (Google "placenta + recipes" for a particularly unique way to spend an afternoon.) She says the capsules helped ease her postpartum depression and cramping, and increased her lactation.

Pickens, concerned only with the culinary challenge, opted for rumaki because it seemed like the best way to taste the organ. She invited the placenta donor, Suzanne Geneste de Besme, to partake, but de Besme declined.

"My husband and I are both very adventurous eaters," de Besme says, explaining why she supported the club's mission, "but for some reason, eating placenta is where I draw the line."

The smell in Pickens' kitchen as people filtered in was bacon-heavy, with a tinge of organ meat. A few cheeses sat on a cutting board for snacking, but stayed wrapped and ignored.

When all seven attendees arrived, Pickens pulled the rumaki out of the oven. Participants hesitated, then chose their skewers. After some eating, there were murmurs of "delicious" and "tastes like bacon." To a respectful abstainer, the meat appeared to be chewy, though to be fair, few were chewing - most were just swallowing.

As the group went for seconds, Pickens offered, "You know, people eat lamb placenta all the time."

"Where can you find it?" asked someone.

"Oh, you can order it on the Internet."

The next meeting of the Food Adventure Club is May 13. The scheduled subject is dining in the dark. Go to facebook.com/pages/SF-Food-Adventure-Club for details.