‘Starchy’: A new primary taste?
Scientists long believed that humans could register only four primary tastes: sweet, sour, salty, and bitter. Seven years ago, they added a fifth: umami (savory). But a new study suggests there may be a sixth: the “starchy” taste of complex carbohydrates such as bread and pasta, which might partly explain why people crave carbs. Researchers from Oregon State University found that volunteers who were given liquid solutions containing complex carbohydrates could detect a starchy taste. “Asians would say it was rice-like, while Caucasians described it as bread-like or pasta-like,” lead researcher Juyun Lim tells New Scientist. “It’s like eating flour.” To rule out the possibility that the volunteers were simply picking up on the sugar molecules that are produced when carbohydrates break down, researchers gave them blockers to prevent them from tasting sweets. The volunteers were still able to identify and describe the starchy taste in the solutions. “Every culture has a major source of complex carbohydrate,” Lim says. “The idea that we can’t taste what we’re eating doesn’t make sense.” Researchers have yet to find specific starch receptors on the tongue, but the finding adds to growing evidence that human taste is more complex than previously thought. Other flavors currently being investigated as potential primary tastes include calcium, fatty acids, and the metallic taste of blood.