Pho Secret Ingredients: Dried Earthworms (Sa Sung)

If you read Saveur magazine, you may have seen the northern pho (pho Bac) article that I wrote for the March 2011 issue. One of the ingredients that I mentioned in the story was sa sung (Sipunculans), dried peanut earthworms that add a unique savory sweetness to the broth. My cousin Quyen, Metropole Hotel Chefs Nguyen Thanh Van and Nguyen Thi Kim Hai, along with other Hanoians that I interviewed for the story talked about using the worms for their pho broth. They spoke of cooking with sa sung in a matter of fact manner.

I’d read about sa sung in Chef Didier Corlou’s cookbook, Ma Cuisine du Vietnam, but he wasn’t clear about what the worms did to the broth. Plus, the dried worms are not available abroad.

In the Saveur story (I know, it’s terrible that my surname was misspelled but it happens), I suggested dried scallops as a substitute. They work very well. However, sa sung is a nifty ingredient that I want to highlight on this site. For those of you visiting Vietnam, it’s a great food travel souvenir. Maybe there’s a food importer and distributor who will make them available for cooks outside of Vietnam! Below is information that I’ve gathered on the dried earthworms.
What are Sipuncula?
They’re marine (sea) worms that were first described in 1827 by a French zoologist. There are over 140 different kinds of them, and some are teeny tiny (2 millimeters long) while other can be as long as 28 inches.

Sipuncula nudus, between 6 and 10 inches long, is the kind employed by cooks in Vietnam and Southern China, primarily in Guangong, Hainan, Guanxi and Fujian. The Chinese names include: beihai shachong (北海沙虫, north sea sandworm) and tusun (土笋, earth bamboo shoot). The worms are sometimes featured in aspic as a Chinese delicacy.

In English, Sipuncula nudus is often referred to as peanut earthworms. I suppose it’s because the worm can look like a peanut. It doesn’t have segments but has a large flask-like section with a proboscis that can retract. Think of pushing the finger of a glove inside out.