Wednesday, December 22, 2010

A Sweet Potato, By Any Other Name…


No table would be complete without them when holiday dining takes center stage; Yukon Gold, Russet, Yellow Finn, Red, and a whole mess of varieties that can be boiled, baked, roasted, steamed, mashed, fried, scalloped, tossed in stew or used as a battery. They are potatoes, a staple of diets around the Western world and boasting a fairly impressive résumé that began roughly 4,000 to 5,000 years ago in Peru. Spanish travelers then introduced them to Europe, and from there the easy-to-grow perennials became commonplace among colonies and settlements, in part because they served as a cheap source of nutrition (as well as being used to brew vodka). With such a rich history and countless culinary uses, it's no surprise that this super spud has become such a staple in holiday cuisine. What about the potato's cousin, the oft-overlooked sweet potato? Hath not a tuber eyes? Cut out its roots, does it not propagate? Does it not make for an awesome dish of candied yams?

Actually, it does not. Sweet potatoes, despite what your local grocery posts on strategically placed signage, are not yams. Welcome to one of the perils of being a North American: unlike the rest of the world, Canadians and Americans lump sweet tubers together with yams, assuming the latter is simply a white-fleshed version of the former, which tends to feature orange flesh. So what is the difference? Yams are a root originating in West Africa and New Guinea, believed to have originated somewhere in the ballpark of 8,000 B.C.E. Unlike potatoes, yams can be stored for up to six months without the use of refrigeration, a valuable trait in a region routinely devastated with food shortages and famine. In contrast, potatoes and sweet potatoes have a thinner skin that yields quickly to fungus, resulting in a shelf life of several weeks (ten to twelve months using commercial storage techniques).

Sweet potatoes are native to Central America, having been domesticated some 3,000 to 4,000 years ago. Island-hopping Polynesians introduced the plant (it's a relative of the morning glory!) to Pacific Islanders, eventually reaching as far away as Hawaii and New Zealand. Crucial to the success of these native peoples was their ability to see in low-level light, boosted by the incredible levels of beta carotene found in sweet potatoes. A good source of B6, potassium, and manganese, orange-fleshed spuds are truly a super food with much diversity. Like its white-fleshed cousin, the sweet potato can be cooked in a number of ways, making it a very popular addition to Asian cooking (Koreans apparently love it as a topping on pizza).

So what exactly are you getting when you purchase "yams" from the grocery store? One seriously mislabeled product, though the United States Department of Agriculture isn't helping any; it requires that if the product is going to be incorrectly labeled as "yams" it should also read "sweet potato" somewhere nearby. Yams are capable of reaching 7 feet in length, and are a rarity in the United States, so why the continued confusion? It's far simpler to mislabel a product. After all, consumers purchased VitaminWater hoping to find a great-tasting alternative to water that had been richly fortified with vitamins and minerals, only to discover they had actually bought sugar water. What's in a name, anyway?

Here is a great roasted root vegetable recipe that uses sweet potatoes (and not the difficult to find yams we are so unfamiliar with here in the states).