GROCERIES
What's the Difference Between Sweet Potatoes and Yams?
JANET RAUSA FULLER

“What's the Difference Between Sweet Potatoes and Yams?”

There is no mistaking the sweet potato casserole, no matter what sort of magic (marshmallows, candied pecans, streusel, etc.) you sprinkle on top.

There is, however, plenty of mistaking the sweet potato itself.


So let’s get things straight: A sweet potato is not a yam. A yam is not a sweet potato. And by the way, a sweet potato isn't even a potato—nor is a yam.

WORLDS APART
They're two different plants. The sweet potato is in the morning glory family, while yams are related to palms and grasses.

And they grow in different parts of the world: yams in Africa, where they originated, and also Southeast Asia, the Caribbean and Central America. Sweet potatoes in the United States, with North Carolina leading the way in production.





So at a typical supermarket, what you're buying is an American-grown sweet potato. True yams are imported and a rare find outside of ethnic grocery stores.

HOW TO TELL THEM APART
A sweet potato has tapered ends and thin, smooth skin and flesh that can range from light beige to burnished orange to purplish, even.

A yam is cylindrical, typically white-fleshed—there is a purple variety, too—and has rough, dark, almost hairy skin.

"They are just... ugly," said Kelly McIver, executive director of the North Carolina Sweet Potato Commission.

They taste very different, too. Yams are starchy and dry. Sweet potatoes are, well, sweet and moist, some more than others.

SO WHY THE CONFUSION?
The prevailing theory seems to date to the slave-era South, where sweet potatoes were established as a crop and dubbed yams, a shortened form of the African word nyami, which means "to eat," McIver said.

According to the Louisiana State University AgCenter, "yam" as a marketing term for sweet potatoes really took hold in the 1930s after Louisiana scientists developed a particularly sweet orange-fleshed variety, the one we're accustomed to these days.

Labels on produce bins at the supermarket don't help much. You might still find "yam" and "sweet potato" used interchangeably or in tandem. The FDA, which regulates food labeling, doesn't have a so-called standard of identity for either sweet potatoes or yams, so either term works.

“‘Yam’ has just kind of stuck,” said McIver.

In North Carolina, home to more than half of the U.S. crop, the sweet potato harvest starts in mid- to late-August, said third-generation organic farmer Stanley Hughes of Pine Knot Farms in Hurdle Mills, N.C.

Peak season runs until December. "That's when they're at the best, when all the flavors are saturated throughout," he said.

SHELF LIFE
The shape and size of sweet potatoes makes no difference in flavor. Just look out for any obvious dings or rotting spots when buying them.

At home, take them out of the plastic bag and keep them in a well-ventilated container in a cool, dry spot. The basement is good; the refrigerator, never. McIver stores hers in the garage. They'll keep for up to a month under ideal conditions, she said.

Cooked puree—perfect for pie or that inevitable, unmistakable don’t-call-it-yam casserole—will keep frozen in airtight bags for at least a year.

http://www.epicurious.com/ingredients/whats-the-difference-between-sweet-potatoes-and-yams-article?mbid=social_facebook

Last edited by Goose (11/26/2016 10:43 am)