That's a fine little yam, ma'am," I told Tara Smith, the LSU AgCenter's sweet potato extension specialist and coordinator of the Sweet Potato Reseach Station in Chase, Louisiana.
I had just finished a taste test comparing Evangeline (left), a new variety of sweet potato developed by the LSU sweet potato folks with the Red Garnet yam (center) and the Beauregard sweet potato (right). Smith was shocked by my experiment since the Evangeline is still in the testing phase and not available to the public. I confessed that I got mine from a sweet potato spy. The Evangeline won the taste test hands down.
The African yam is a different species from the sweet potato. There are no true yams grown commercially in the U.S. But back in the 1950s, in an effort to distinguish their creamy sweet potatoes from the drier Eastern product, Louisiana growers started calling their sweet potatoes "yams." It was a marketing gimmick, but the name stuck. Today, the names yam and sweet potato are more or less interchangeable in the U.S.
The Puerto Rican yam was the preferred Louisiana sweet potato back in the day. Then came the Jewel yam. Today both are popular heirloom varieties grown by gardeners. But the Jewel ceased to be profitable for farmers. Texas got out of the sweet potato business and Louisiana was about to follow suit.
Then in 1987, the late Larry Rolston of LSU came up with an improved sweet potato variety. His high-yielding and disease-resistant strain saved the failing Louisiana sweet potato industry. A Civil War buff, Rolston named his sweet potato after the French-Louisiana Confederate General Pierre Gustave Toutant Beauregard.
The flavor of the Beauregard sweet potato is subtle. Lower in sugar, it almost tastes like a cross between a sweet potato and an Idaho spud. Which is fine if you're eating baked sweet potatoes with your pork roast. But for sweet potato pie, candied sweet potatoes and other traditional recipes, the Beauregard wasn't quite as useful as sweeter varieties such as the red-skinned garnet.
In 2007, 20 years after the introduction of the Beauregard, LSU's Don LaBonte came up with the Evangeline. The Evangeline has similar yield and disease-resistance characteristics, but it offers consumers higher sweetness in a traditional brown-skinned, orange-fleshed sweet potato. Tara Smith told me that the Evangeline averages 10% more sugar and twice the sucrose as the Beauregard. The flesh is also a deeper orange.
The Evangeline was used in test plantings in 2008, but the tests weren't conclusive because of abnormal rainfall due to hurricanes. Farmers who did produce Evangeline sweet potatoes will use them as seed potatoes this year. Of course, a few Evangelines "fell off the truck" on the way to the barn and wound up in taste tests like this one. It will be awhile before the Evangeline sweet potato starts turning up in your local grocery store. But hey, we all need something to look forward to, right?
-Robb Walsh