The human tongue can detect five basic tastes: sweet, sour, salty, bitter, and umami (also called savory). Each of these tastes helped our ancestors survive by alerting them to poisonous foods and making safe, more nutritious foods tasty. Now researchers think there may be a sixth basic taste: starchy.
A taste for starchy foods like bread, pasta, and rice makes sense, according to Juyun Lim and her colleagues at Oregon State University. After all, complex carbohydrates are an important source of energy. In the past, these long chains of sugar molecules were thought to have no taste. It’s only when they’re broken down into simple sugars in our saliva that our sweet taste receptors kick in.
But in the Oregon State study, subjects identified a starchy taste in liquids containing complex carbs, even when they were given a compound to block their sweet taste receptors (1).
So what does this mean for us? The idea that we may have a “starchy tooth” is interesting, but not all experts are ready to declare it the sixth basic taste. “Even if starch were the sixth taste sensation, it would not necessarily explain why people like foods with high carbohydrate content like pasta and pizza,” said Becky Smith, MEd, RD, a retired food science professor from the University of Cincinnati. “Since we see and smell food before we put it in our mouths, we can't discount the importance of these sensations in why we enjoy specific foods," she said.
For now, watch for more studies on the sixth basic taste. Besides starch, other tastes in the running include fat, alkaline, metallic, calcium, and water-like.
By Hollis Bass, MEd, RD, LD
(1) Lapis TJ, Penner MH, Lim J. Humans can taste glucose oligomers independent of the hT1R2/hT1R3 sweet taste receptor. Chem Senses (2016). doi: 10.1093/chemse/bjw088.
Stephanie Ronco has been editing in a professional capacity for the past 10 years. In addition to her work as an editor, Ronco has also served as a ghostwriter and writing tutor. A voracious reader, Ronco loves watching language evolve and change. When she’s not delving into her latest project, Ronco can be found teaching acting classes, performing in community theater, or sailing with her husband.