By Jeanne Foels, Marketing & Outreach Coordinator
For our third week of celebrating National Sweet Potato Month, we think it’s time to demystify a common point of confusion: what’s the difference between a sweet potato and a yam? Are the terms interchangeable?
According to our friends at the Wedge Co-op and other sources, if the tuber in question is grown in the United States, it’s most likely a sweet potato, no matter what the label reads. Ninety-five percent of yams are grown in Africa, and these large vegetables are starchier and drier than sweet potatoes. Though they are both tubers, sweet potatoes and yams are not related, and they vary in taste and texture.
The standard story about the start of this mix-up assigns the confusion to African-born slaves calling sweet potatoes “yams” because they resembled the yams they knew in Africa. Since there are two main varieties of sweet potatoes, the U.S. Department of Agriculture decided to label the sweeter, orange-fleshed kind as “yams” and the paler-fleshed kind as “sweet potatoes.”
Today the USDA requires labels with the term “yam” to be accompanied by the term “sweet potato.” Unless you find real yams in international markets, you are most likely eating sweet potatoes whenever you buy “yams” from grocery stores.
Now for a treat after all that etymological history! Here’s a delightful sweet potato cake that can be made in advance of special occasions. Use the softer, sweeter type of orange-fleshed sweet potato for this recipe — and quiz your dining companions on its real name with your new-found knowledge.
Sweet Potato Cake with Cream Cheese Frosting
Adapted from Kitchen Confidante
(Makes one 9″ round cake or a 13″×9″ rectangular cake)
2 cups sugar
2 cups all purpose flour
2 tsp. baking soda
2 tsp. cinnamon
1/2 tsp. salt
4 large eggs
1 1/4 cups canola oil
3 cups grated sweet potato (about two sweet potatoes)
1/2 cup butter, softened
8 oz. reduced fat cream cheese, softened
2 cups powdered sugar
1 tsp. vanilla
1. Preheat the oven to 350 degrees. Butter the baking pan. If using a round springform pan, use parchment paper on the sides of the pan, if desired.
2. In a medium bowl, whisk together the sugar, flour, baking soda, cinnamon and salt. In a large mixing bowl, beat the eggs until light and frothy. Beat in the oil. Add the flour mixture in two additions, until just incorporated, scraping down the sides of the bowl. Stir in the sweet potato.
3. Pour the batter into the pan and place in the oven. If using a 13″×9″ pan, bake for 45-50 minutes or until the cake is springy and a toothpick inserted into the middle comes out clean. If using a springform pan, lower the temperature to 325 degrees and bake for 45-50 minutes or until a toothpick comes clean.
4. Remove from oven and let cool completely. If using a springform pan, remove sides and invert onto a wire rack or serving plate. Remove bottom of springform pan. Wrap the cake well and refrigerate until ready to frost. This can be done a day or two in advance.
5. Make the frosting by whipping together the butter and cream cheese. Add the vanilla. Slowly add the powdered sugar and whisk well. Frost the cake and refrigerate.
6. Remove the cake from the refrigerator about 10-15 minutes prior to serving.