Weekly dose of wonder: The flavor and history of umami

ARI SHAPIRO, HOST:

Have you ever wondered, why is this meal so delicious? The answer might be umami. The word means delicious taste in Japanese. Umami refers to the savory, meaty flavor you can find in fish broth, mushrooms or tomatoes. It's considered the fifth primary taste, alongside sweet, sour, bitter and salty. Umami has a character and history all its own, as NPR's Yuki Noguchi reports for our series on things that fill us with wonder.

YUKI NOGUCHI, BYLINE: Having Japanese immigrant parents meant I grew up eating foods steeped in umami - soy sauce, miso paste and dashi, a broth made from seaweed, shiitake mushrooms or dried flakes of tuna. Those ingredients, in particular, are cornerstones of Japanese cuisine. So umami was a dinner table word in my family long before it entered the American lexicon. I didn't know what it was exactly. I thought of it as the hero that gave food a yum factor. It's savory and salty, like a ramen made with bone broth. It can also have tang, like marinara sauce or cheese-flavored popcorn. It seemed odd that English would have no equivalent word. Then again, I get why umami evades description. Almost everything about it is mysterious and complex, from how it tastes to its history and its fight for legitimacy. Oxford psychologist Charles Spence, who studies taste perception, says a lot of that probably goes back to the unusual way we sense umami.

CHARLES SPENCE: It only comes alive, it only becomes delicious when it's combined with an aroma. And hence, it's unlike the other tastes. Sweetness is sweet whether or not you can smell anything. Same for salty. Same for bitter.

NOGUCHI: On its own, umami doesn't taste strong or particularly good. But, says Spence, when combined with other foods, umami punches up flavors of protein and salt while also weaving in other tastes, like sour.

SPENCE: All the tastes kind of interact with one another, sometimes suppressing, sometimes enhancing the other tastes.

NOGUCHI: This complexity might also help explain why umami wasn't isolated and recognized as a taste until relatively recently. Chemist Kikunae Ikeda, a Japanese man, was inspired by his wife's broth. He isolated the compound glutamate in 1908 and called it umami. But it would take nearly a century and the more recent discovery of glutamate receptors on our tongues before Western cultures accepted that umami was a primary taste. That resistance, Spence says, is rooted in discrimination.

SPENCE: Why it's taken so long for umami to be accepted - sort of racist undertones there. It sort of came from the East and so perhaps with less acceptance of it.

NOGUCHI: And, he says, that still powerfully shapes consumer perception. Soon after its discovery, a Japanese company sold umami in salt-like form as monosodium glutamate - the notorious MSG. Its notoriety stems from a 50-year-old urban myth that MSG used in Chinese restaurants causes headaches. John Hayes is a behavioral food scientist at Penn State.

JOHN HAYES: Yeah, it's a zombie myth that will not die.

NOGUCHI: Hayes says many people still don't realize that, despite its borrowed Japanese name, umami exists in all cuisines.

HAYES: Pepperoni pizza - it's just a huge umami bomb. There's umami from the cheese, umami from the tomatoes. There's umami from the cured meats. If Chinese restaurant syndrome were real, then that pepperoni pizza should give you a giant headache as well.

NOGUCHI: The irony of that myth is that umami can make food healthier and more satisfying. Again, through its mysterious interactions with other flavors, umami can make a thing taste saltier or richer without adding sodium or fat, for example. And flavor chemist Arielle Johnson notes umami-rich foods tend to be fermented or slow-cooked. They take time to prepare.

ARIELLE JOHNSON: Umami is a particularly good example of careful mixing and tending and aging and shepherding of ingredients until they become something that is delicious to us.

NOGUCHI: Which brings me back to my childhood notions. Umami does indeed possess mysterious qualities that are hard to describe, even among scientists. And umami, in many ways, reflects the love and deliciousness that goes into a dish. Plus, there's a profound attribute of umami I had not appreciated as a child - its ability to overcome bias and discrimination by simply demonstrating its universal human appeal.

Yuki Noguchi, NPR News. Transcript provided by NPR, Copyright NPR.