• Peter Barakan


    Born in London in 1951, Peter earned a degree in Japanese from the University of London's School of Oriental and African Studies (SOAS). An expert on diverse forms of popular music, Peter is also a well-known TV and radio presenter. He has lived in Japan for 40 years and has a deep understanding of the language and culture.

  • Matt Alt


    Born in Washington D.C. in 1973, Matt's interest in Japan was kindled by robot toys in his childhood. He worked as a translator for the U.S. Patent and Trademark Office before co-founding a company that produces English versions of Japanese comics and video games. He also writes extensively about cultural trends including yokai, ninja, emoji, and more.

  • Norinaga Oishi

    Main guest

    President of the Japan Katsuobushi Association. The second-generation head of a katsuobushi plant in Yaizu, Shizuoka Prefecture, Norinaga Oishi has spent years working with this key Japanese ingredient. In 2007, the Japanese government awarded him the Yellow Ribbon Medal of Honor, as recognition for professional achievements that make him a role model for others in his field.


December 1, 2016


*You will leave the NHK website.

In 2013, Japanese food, washoku, was added to UNESCO’s Representative List of the Intangible Cultural Heritage of Humanity, a move that put this already highly regarded cuisine still more firmly in the global spotlight.

In contrast to the other national (French, Mexican), and regional (Mediterranean) culinary traditions to receive this accord, washoku is characterized by rather subtle flavors, including a gently salty smokiness with a savory hint of umami that accentuates the natural taste of the central ingredients themselves, from seafood to vegetables.

Alongside soy sauce and miso, one of the primary seasonings is katsuobushi––the secret behind the dashi stock that provides the mouthwatering body of Japanese soups and hotpots, and an ingredient that has few parallels in other cuisines around the world.

So what is katsuobushi, exactly? Many diners from overseas first become aware of the substance when served okonomiyaki savory pancakes or yakisoba fried noodles topped with a handful of paper-thin kezuribushi, ruddy-tinged shavings that seem to writhe and dance in the heat rising from the dish they adorn.

This rather surprising spectacle can lead the uninitiated to surmise that they have been served a still-living organism. Yet if one should happen to notice the chefs preparing this garnish, you will see that the hard, dark substance they are grating, using a plane-like tool with a box attached, actually resembles a piece of wood.


Sampling different kinds of katsuo dashi at a Japanese restaurant.


Peter gets a workout shaving his own katsuobushi.

Katsuobushi is actually (and perhaps unsurprisingly, given the name) made from katsuo, or skipjack tuna. This fish, sometimes erroneously referred to as bonito, migrates through Japanese waters each year, and the first catch (or “hatsu-gatsuo,” which typically comes in late spring or early summer) has for centuries been prized by the nation’s gourmands.

Before refrigeration techniques facilitated the wider transport of fattier maguro (bluefin tuna) in the early 20th century, katsuo was a staple of sashimi and Edo-style sushi. It is also frequently eaten as a main dish, either preserved in a sweet-salty sauce as tsukudani, or gently seared on the outside as katsuo-tataki.

As mentioned earlier, though, perhaps the most ubiquitous use of katsuo is as katsuobushi. But how do we get from lean red fish to these hard, woody blocks? While fattier modori-gatsuo, caught further north later in the year as they return to warmer, more abundant waters with winter approaching, is prized for its taste, katsuobushi production usually begins with leaner fish caught to the south, including Japan’s southwestern regions, such as Shikoku and Okinawa.

The heads and guts are removed before each fish is cut lengthwise into four chunks of roughly the same size. These are then simmered for an hour or two in near-boiling water, before being cooled in chilled water as they are deboned by hand.

Once this process is complete, the skipjack is smoked over oak or other woods, both to prevent deterioration and to imbue the fish with its distinctive, smoky aroma.


At this plant, katsuobushi is still smoked the traditional way.


It is only after a lengthy process of smoking that katsuobushi is ready for the kitchen.

The process of smoking takes a full month of daily smoking sessions (although premium grade examples may even be aged for a couple of years, with other treatments such as inoculation with culinary mold also used to enrich the flavor). In the early stages, the readiness of the smoked fish is gauged by its flexibility, although after three or so weeks when the blocks are too stiff to bend, sound becomes a more useful indicator.

Once you have hard, stridently resonant blocks that seem almost fit for use in the percussion section of an orchestra, the katsuobushi is ready. An evenly dark, almost ruby-like sheen throughout the piece when broken in two gives confirmation of consistently low water content throughout.


Peter Barakan and Norinaga Oishi examine katsuobushi samples from various stages in the month-long smoking process.


A broken piece of katsuobushi​ reveals a ruby red interior.

To prepare katsuobushi dashi stock, the shavings (best taken fresh, but nowadays most often bought in sealed plastic packs to prevent spoiling) are steeped in boiling water, and then the heat is turned off. Once the katsuobushi sinks to the bottom, the broth is ready to be filtered for use in soups and other dishes.

However, although this preparation provides very much the archetypal flavor and aroma of much washoku, any vegetarians reading this column with dismay need not fear. It is fully possible to enjoy authentic Japanese dishes prepared with a dashi made from konbu kelp or shiitake mushrooms, which can provide many of the same flavor benefits in terms of accentuating umami. And, given advance warning, many restaurants will be able to accommodate such needs.


Premium-grade honkarebushi is deliberately inoculated with a mold whose microbial action further enriches the flavor.


Matt Alt finds out about the significance of katsuobushi to Okinawan cuisine.


Smoky kachu soup is a trusty Okinawan comfort food for those feeling hung-over or under the weather.


Carrot shiri-shiri is an Okinawan dish loaded with katsuobushi umami.



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