Many of you may think sweet potatoes and yams are the same thing. I was certainly unclear on the difference. I was under the assumption that a yam was a type of sweet potato or that a sweet potato was a type of yam. After talking to some friends, I realized that many of us are in the same boat. We know that the sweet potato is Michelle Obama's favorite fall vegetable, but we need to dig deeper. What really is the difference between sweet potatoes vs yams?
According to The Kitchn, the two are actually very different. If you're like me and thought that a sweet potato was a type of yam, you've been living a lie. They are, however, similar in that they're both root vegetables and come from flowering plants.
Sweet potatoes were discovered by Spanish explorers in the Americas, and actually have many varieties. While you may be accustomed to the classic orange colored-ones you have at Thanksgiving dinner, the flesh can also be yellow, white, or orange-red as well. The skin can be white and yellow, red, purple, or brown and the shape is elongated with tapered ends.
The two main types of sweet potato are firm and soft. Firm sweet potatoes have the paler flesh, while soft sweet potatoes have orange flesh that becomes creamy when cooked. According to the book, The Oxford Companion to Food by Alan Davidson, a sweet potato is not even related to the ordinary potato, but is of American origin.
True yams originated in Africa, Asia, and other tropical areas. Yams are actually related to lilies, and are a root of the Dioscorea genus. They can be the same size as an ordinary potato, or they can grow as large as five feet. The shape of a yam is cylindrical. Their flesh is purple or reddish, while their skin is bark-like.
Yams are not commonly found in grocery stores. If you do see "yams" in the grocery store, it's probably a sweet potato that's labeled as a yam. The reason sweet potatoes may be labeled as yams is that the soft sweet potato slightly resembles a yam, and the name stuck, even though it isn't a yam. True yams may be found in international markets that have Caribbean food.
Culinaria: The United States: A Culinary Discovery by Randi Danforth, Gary Chassman, and Peter Feirerabend shares that sweet potatoes was discovered by a Dutch explorer in Louisiana. As it turns out, Louisianans actually call their sweet potatoes yams in order to separate them from the many sweet potato varieties. The word "yam" comes from the African Senegalese word nyami. These "yams" are not true yams, but the name has remained.
Yams also contain less vitamin A and C than sweet potatoes, but are high in potassium and fiber. Yams are starchier than sweet potatoes and typically eaten boiled but are also eaten roasted, fried, grilled, or baked.
The Oxford Companion to Food also states that edible yams must be cooked before eating to eliminate the bitter substance dioscorine. The taste of cooked yams is starchy and bland, and it may be slightly sweet. Yams can also be used medicinally.
Now that you know the difference between sweet potatoes vs yams, you can people who think they're the same thing that despite how these foods are often marketed, they've probably never even had a yam before!