The element calcium is essential in our body for muscle contraction, cellular communication and bone growth. Being able to feel it in our food, therefore, seems like a useful tool for survival. It seems that the mice have it all figured out, more or less. Recent research has revealed that rodent tongues have two taste receptors for calcium.
One such receptor has been found in the human tongue, although its role in directly tasting calcium is not yet established, Tordoff said. However, it's clear that calcium has a flavor and, contrary to intuition, most mice (and humans) don't like it. People have described it as something bitter and calcareous, even at very low concentrations. Tordoff believes that our calcium flavor could exist to avoid consuming it in excess.
Hypersensitivity to calcium-rich foods, such as spinach, could help explain why four out of five Americans don't get enough calcium. “There's a strong connection between people dislike vegetables and calcium,” Tordoff said. As for milk and other calcium-laden dairy products, the calcium it contains binds to fat, so we don't taste too much of the mineral, Tordoff said. That calcium receptor could also have something to do with a candidate not related to the sixth flavor called kokumi, which translates to taste in the mouth and flavor.
Kokumi has been enacted by researchers from the same Japanese food company, Ajinomoto, who helped convince the world of the flavor of the fifth basic flavor, umami, a decade ago. If that all sounds a little vague, it is also vague for Western scientists. “The Ajinomoto representatives visited Tordoff's group and gave us foods that they say are high in kokumi, but we have no idea what they're talking about,” he said. Kokumi may be something that the Western palette isn't in tune with.
At the opposite end of the taste sensation of hot peppers is the minty, fresh sensation of mint or menthol. The same sensory perception trick works here: activated touch receptors, called TPRM8 in this case, trick the brain into detecting cold at normal oral temperatures, Hayes said. However, there is an argument that the sensation of temperature, both in the genuine sense and in the confusing phenomenon of itching and freshness of the brain, deserves to be in the pantheon of basic flavors. Interestingly, the Germanics dating back to 1500 considered the sensation of warmth as a flavor, Hayes said, and the modern debate over the state of temperature is far from over.
It is not yet known if our tongues can taste fat or simply feel its creamy texture. It's clear that many of us enjoy fatty foods, from well-marbled steak to just about anything fried. Interestingly, subjects with greater fat sensitivity ate fewer fatty foods on the menu and were less likely to be overweight than those with low sensitivity. Bartoshuk, who was not involved in the research, noted that fatty acids tend to taste bitter in the mouth, and believes that the tactile fibers of the taste buds instead perceive the creamy thickness of fat droplets that don't break down.
See what other Food52 readers are saying. All animals, including humans, need food to survive. And we can't eat anything. It may be possible to eat wood or dirt, but these things aren't actually considered “food” because they don't provide us with any nutrition.
So how do we know what things we should eat and what we shouldn't eat? The answer is taste. Each basic flavor (sweet, sour, salty, bitter and umami) is a message that tells us something about what we put in our mouths, so that we can decide if we should eat it. .