Geneticist Danielle Reed has been working in taste science for decades but says some of the most exciting – and definitive -- discoveries have been recent.
In the last 12 years, researchers have isolated taste receptors for sweet – as well as the lesser understood basic taste – umami. Umami (pronounced: ew-mommy) is often at the heart of intuitive succulent cooking. Grandmothers in southern Italy, for example, toss a handful of cherry tomatoes into a clear broth, or slip the rind of parmesan cheese into a pot of simmering beans.
“Without consciously knowing what they're doing, they add the taste of umami to the dish,” says Brooklyn-based cookbook author Rozanne Gold.
Wild mushrooms, fresh picked corn, dried seaweed and fish sauce all have lots of savory umami taste, and high levels of an amino acid called glutamate. Glutamic acid tips off the taste buds, and then an umami alert rushes to the brain.
Umami deepens flavor and adds meatiness, says Gold, who calls herself the "Diva of Simplicity."
Her latest book is Radically Simple: Brilliant Flavors with Breathtaking Ease.
“When you only have three ingredients to play with each one really counts, so instinctively I work with foods that are umami rich,” she said. “What MSG does for a dish, that already exists naturally in some foods.”
The concept is age-old but a Japanese chemist, Kikunae Ikeda coined the term “umami” in the early 1900s. Everyday taste testers struggle to categorize umami, says neuroscientist Alexander Bachmanov, because the taste rarely stands alone. And that, he says, may explain why a scientist, not a chef, finally gave umami a name.
You can put a sugar cube on your tongue to sample pure sweet, or lick sodium chloride to explain salty. Umami is harder to single out, says Bachmanov, a researcher at the Monell Chemical Senses Center in Philadelphia.
“If it's glutamic acid, it will also have some sourness in addition to umami. If it is monosodium glutamate (MSG), it will have a little bit of saltiness in addition to umami,” he said.
That something else, is now considered the fifth taste. When scientists isolated the first umami taste receptor in 2000, umami officially joined the big four--sour, salty bitter and sweet.
Bachmanov says our taste buds are “tuned-up” to taste glutamic acids, and there's likely an evolutionary reason why most people perceive umami as pleasant.
Our sense of taste is like a detection system, constantly analyzing and helping us decide whether to eat or avoid a food. Glutamic acid--the tip-off for the umami taste--is a building block of protein.
“If a food is sweet, it likely contains carbohydrates. If it has umami taste is probably has protein. Our body gets the indication that the food contains protein, that it's nutritious, good for us,” Bachmanov said.