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This story begins in Tokyo, where the Japanese chemist named Dr. Kikunai Ikeda.

The story goes that back in 1908, Dr. Ikeda was contemplating Dashi.

This is Sarah Tracy, historian of food science.

Dashi is the Japanese soup stock, uses the flavor base of so many dishes, miso soup, ramen, sakeaki.

Anyway, back in the early 20th century, Dr. Ikeda was trying to figure out what made Dashi so delicious.

He felt clear that he was tasting something that was not adequately described by the four accepted chemical tastes.

Those four tastes being sweet, salty, sour, and bitter.

But in the Dashi, Ikeda recognized something different, a distinct savory flavor.

According to the story, he set out to isolate what this flavor was, and he isolated it from kombu, which is a really common type of seaweed, native to Japanese cuisine.

Ikeda got to work on his Dashi, like a chemist would, distilling the flavor of this seaweed in a lab,

removing compounds like manatol, potassium chloride, and the sodium chloride until a single substance began to crystallize.

Glutamate.

Glutamate is just in the amino acid, a building block of protein, and Ikeda called the taste that comes from glutamate, umami.

And in 1909, published a paper in Japanese in the Journal of the Tokyo Chemical Society, he wrote,

It is the peculiar taste which we feel as umai, meaning brothi, meati, or savory, arising from fish, meat, and so forth.

I proposed to call this taste umami for convenience.

Ikeda had discovered a fifth taste, but it would take nearly 100 years for umami to be accepted by the broader scientific community.

Why?

Today on the show, as part of our Taste Buddy series, we'll talk to shortwave producer Chloe Weiner about this century old delay between umami's identification in Japan and its recognition worldwide.

And ask why it took science so long to accept what's right under its nose.

I'm Emily Kwong and you're listening to shortwave, the Daley Science podcast from NPR.

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