In 1908, Japanese chemist Kikunae Ikeda coined the modern term “umami” to describe a distinct savory taste he attributed to compounds of the natural amino acid, glutamate. But for centuries before that, masters of Japanese cuisine had already understood its secrets.
Umami is by no means exclusive to Japan, and almost every cuisine in the world has developed ways of producing or enhancing it. In the West, umami is found in the browning reactions that lend their flavor to roasted meats, crusty bread and rich stocks, as well as the processes of aging cheese, curing meat or drying mushrooms. In Asia, umami is more commonly created by salting or fermenting fish or vegetables to create foods such as fish sauce, belacan or kimchi.
What distinguishes umami in Japanese cuisine is the variety of forms it takes, along with its clarity of flavor. Often the taste of umami is extracted as purely as possible, without combining its sources with rich meaty broths or pungent fermented seafood.
One of the purest flavors of umami is found in the dried kelp known as kombu, a staple of Japanese cuisine. Takashi Okui’s family has been trading kombu in the sea port of Tsuruga in Fukui prefecture for nearly 150 years. He knows umami as well as anyone, but is quick to point out that good kombu is not just about umami, but finding a balance of flavors.
Different varieties of kombu exhibit varying strengths of umami, which in turn make them suitable for a range of purposes. According to Mr. Okui, Tokyo restaurants favor the stronger umami taste of rausu kombu, while the more delicate cuisine of Kyoto prefers the balance of rishiri kombu.
Mr. Okui has a theory: Aging kombu increases its umami while also allowing other flavors to mellow, producing a more potent, yet also more balanced, flavor. When I visited his warehouse last week, he prepared two stocks for me: one with dried rishiri kombu that had been aged for 15 years and simply infused into cold water, and another made from kombu harvested this past summer.
The contrast was astounding. The younger kombu stock was pungent and reminiscent of the ocean, with a dominant but not unpleasant taste of seaweed. The aged kombu stock, on the other hand, was smooth, golden and rich with umami. It reminded me of a concentrated chicken consommé.
The idea of aging kombu is a relatively new one, and Mr. Okui is its modern-day champion. But like most things in Japan, it has ancient roots. In the Edo period, ships would bring kombu from the kelp forests in Hokkaido to Tsuruga, where it would make the trip overland to Lake Biwa and further on to the culinary centers of Kyoto and Osaka. The path lay on the network of sea and land journeys known as the Kombu Road, a trade route vital for the spread of umami around Japan.
The Hokkaido kombu harvest would occur during the summer months and the kelp would then need to be dried for the sea journey to the mainland. By the time the dried product reached Tsuruga, the winter snows made overland transport impossible until the following spring. In the 1600s, kombu reaching a Kyoto chef would have already been aged for almost a year.
But kombu is just the tip of the umami iceberg in Japanese cuisine. In Aichi prefecture, I watched the fermentation of soybean hatcho miso at the Noda miso factory. Produced in the traditional way to naturally increase the umami of the product, soybeans are steamed and inoculated with koji mold, a key ingredient for sake brewing, then mixed with salt and water and placed into giant cedar barrels to ferment for up to two years, pressed by river stones.
The fermented miso paste is rich in umami flavor itself, but just as exciting for me was the chance to taste true tamari. Many think of tamari as a kind of wheat-free soy sauce, but true tamari is a byproduct of the miso-making process, rising to the top of the barrels as the miso ferments. It is thick and syrupy, the color and texture of motor oil, with a salty, quite overpowering umami taste.
Among kombu, miso, tamari, soy sauce, green tea and dozens of other staples, the sheer number of sources of umami in Japanese cuisine is staggering. Their variety, subtlety and simplicity of flavor are an exciting prospect for any talented chef, offering a broad palette from which to create.
When I visited him, Mr. Okui told me that acclaimed chef Rene Redzepi from Copenhagen’s Noma had recently tasted his 15-year aged kombu, and had seemed quite excited by its possibilities. Perhaps the Kombu Road that has distributed umami around Japan for centuries will soon be branching out around the world.
Around the Table is Adam Liaw’s column for Scene on Asian food and culture.
Adam is a cook, author, television presenter and winner of MasterChef Australia 2010. He has lived, worked and eaten around the world, including Australia, Malaysia, China, India and most recently, spent seven years in Tokyo, Japan. He is perpetually hungry.