Soft Svevo, a new soft durum wheat variety developed by USDA's Agricultural Research Service scientists and their collaborators, could help expand the market for durum wheat.
Traditional durum wheats are primarily grown as a source of semolina — a coarse meal used to make pasta, couscous and other products. However, producing semolina requires specialized mills that can grind durum wheat's rock-hard kernels. This, in turn, has limited the food uses for durum wheat, which comprises 3% to 5% of the total U.S. wheat crop.
Craig Morris, an ARS chemist in Pullman, Wash., has a soft spot for durum, which despite the hard nature of its kernels, is better adapted to hot, arid growing regions of the United States than the more commonly grown bread wheat varieties. Over the past 20 years, he and colleagues have delved into the genetics of wheat kernel development for clues that could broaden the number of products made from durum.
"Turns out, the hard kernel texture has no relationship to the quality of the pasta," says Morris, who is in ARS's Wheat Health, Genetics and Quality Research Unit in Pullman. Rather, it's durum's yellow color and high-protein content that gives pasta its firmness and makes durum the go-to wheat for pasta.
Meanwhile, "the key features of good pasta — bright yellow color and firm 'bite' — have nothing to do with the particle size of the semolina made from the kernels," Morris adds.
Based on that premise, Morris and a team of university and industry scientists set out to create a soft durum wheat whose kernels could be easily milled into a fine flour, instead of a coarse semolina. The flour would be suitable not only for pasta and spaghetti, but also for pizza crust, bread and other baked goods.
The breakthrough came with their discovery of two genes that control kernel texture in soft bread wheats, namely, Puroindoline a (Pina) and Puroindoline b (Pinb). The team moved these genes into a prized Italian durum variety called "Svevo" to eventually produce Soft Svevo, marking the first soft durum of its kind.
Tests show Soft Svevo's flour is similar to soft bread wheat flour. Soft Svevo's high-protein flour imparted an appealing aroma, flavor and yellow color to pizza crusts, baguettes, pan breads and other baked goods the researchers made. In milling tests, Soft Svevo's easily milled kernels translated into energy savings of 75% and water savings of 15%.
Three U.S. firms are now conducting pre-commercial trials of Soft Svevo under license from ARS. Requests for it have come from Japan, South Korea and Morocco.
Sources: ARS Office of Communications, UNL CropWatch