Why umami was dismissed for decades

Why a fifth taste was hard to recognize

For centuries, many accounts of taste grouped sensations into four familiar categories: sweet, sour, salty, and bitter. Umami did not fit neatly into that scheme. It is the rounded, savory quality associated with foods such as broth, ripe tomatoes, and aged cheese—not simply a stronger version of saltiness.

That made it easy to overlook as a separate taste. In everyday foods, savory flavor comes mixed with aromas, salt, and other sensations. A bowl of kelp broth does not arrive as a clean scientific test: its ingredients create a layered impression, and people may describe that impression as “rich” or “savory” rather than as a distinct taste.

From broth to a testable idea

Japanese chemist Kikunae Ikeda focused on kombu, a type of kelp used to make broth. He identified glutamate—a substance that occurs naturally in many foods—as a source of its characteristic savory taste. In 1908, he proposed that this sensation was a basic taste and called it umami, a Japanese word often translated as “savory” or “deliciousness.”

The important step was separating the sensation from the dish. If glutamate could produce a recognizable taste on its own, umami could be investigated under controlled conditions rather than treated as an impression created by a particular recipe. But a proposal is not the same as broad scientific agreement. Researchers needed to establish that the sensation was distinct and that the tongue could detect it through its own taste system.

Recognition followed the evidence

The case became clearer as research identified taste receptors that respond to glutamate. That gave scientists a biological mechanism to connect with the experience people described. It also helped explain why umami can seem especially pronounced in foods where glutamate occurs alongside certain other taste-active compounds.

So umami was not absent from Western diets; the difficulty was recognizing it as a category. People had been tasting it in broth and other foods all along. What changed was the framework for interpreting that sensation—and the evidence that a familiar savor could be both a culinary experience and a distinct basic taste.