Hideaki Matsuo:
Culinary Artist, Ocean Defender

Standing before this unassuming house in the residential district of Senriyama, north of Osaka, it is hard to imagine that we are about to enter one of Japan’s finest restaurants, one that has proudly glittered with three Michelin stars for 13 years. We are at Kashiwaya Osaka Senriyama, a restaurant serving kaiseki cuisine that the founder’s son, Hideaki Matsuo, has hoisted to dizzying dining heights in the space of a few decades.

For guests at Kashiwaya, an uncommon experience awaits: the opportunity to see that excellence can be achieved by way of a responsible culinary vision, however sophisticated the cuisine may be. Though the menu’s dishes unfurl like poetry–a rippling brook of enticing ingredients–the chef only serves these edible elements in small amounts, a sustainable approach that earned him a Michelin Green Star in 2021. “We only use what’s strictly necessary, in the quantity that we can produce without harming nature,” he explains. But his commitment runs deeper still and, while surrounded by his modest staff, preparing a katsuo (bonito) filet smoked with rice straw, he reveals a little more. 

This ambitious and resolute chef believes that a long-term vision of sustainable fishing and marine-species protection is imperative–a conviction shared by Relais & Châteaux and the Association’s partner, Blancpain. Chef Matsuo is considered a friend of the exceptional watchmaking brand–creator of the first true diver’s watch, the Fifty Fathoms, in 1953 and proactive ever since in multiple initiatives to protect the world’s oceans. Blancpain supports and forges close ties with explorers, photographers and scientists who are keenly aware of the incalculable value of maritime resources. So far, Blancpain’s many actions–all pursued with unfailing passion–have generated substantial, measurable results, such as helping significantly increase the coverage of protected marine areas worldwide, adding more than 1.8 million square miles/4.7 million square kilometers. It is therefore not at all surprising that Chef Matsuo feels a bond with the watchmaker. 

Gombessa IV Expedition © Laurent Ballesta

His dawning environmental awareness began in the 2000s, when he could no longer reliably find fish in their usual season at the market. A fish’s ‘season’ is actually the period in which that species is more abundant at fish markets because it is caught in greater quantities, which generally coincides with the spawning period. This means such ‘seasons’ are not necessarily a criterion of sustainability, because fishing practiced in this period is better measured based on a species’ stock levels. Chef Matsuo also recognizes that, with sharply rising temperatures, spring is getting shorter and all of the seasons–so important in Japan–are changing in character, turning his life as a chef upside-down. In 2019, he was among the Relais & Châteaux Japan and Korea Delegation chefs who signed a seafood manifesto on protecting marine resources, one of the United Nation’s 17 Sustainable Development Goals. 

Right: © Nathalie Cantacuzino

Shortly afterwards, he met Yoshifumi Sawada, Professor and Director of the Department of Fisheries/Aquaculture Research Institute at Osaka’s Kindai University. “That encounter gave me access to data and I saw how very serious the problem really is,” says Chef Matsuo. “It came as a shock and I fully understood that we couldn’t carry on this way.” With a few of Professor Sawada’s chef acquaintances, Chef Matsuo established the Relationfish company to address the issues involved in sustainable fishing. “Our primary objective is to protect the environment and the fish. And to raise awareness by holding information days for the public,” he says. “Our most successful project is a farm for a little-consumed fish, the aigo [common names include dusky rabbitfish and pearl-spotted spinefoot], which is found in coastal areas of Japan and feeds on algae.” Its diet, he adds, is a real advantage, because most farmed fish are fed pellets–that is, food made from wild fish, which is one of the causes of overfishing–or fry or fingerlings, again both forms of young fish. “Harvesting fish to feed other fish is a problem for the environment.”

While his pieces of katsuo marinate in a blend of rice vinegar and soy sauce, the chef talks about three species that are particularly threatened by overfishing: tuna (maguro), abalone (awabi) and eel (unagi). “Eel is of special concern: those consumed in Japan are farmed fish, but are raised from fry captured in the natural environment, because we don’t yet fully understand their breeding cycle. So cooks who specialize in preparing eel are eager for us to find a way to have them reproduce in farmed conditions.”

Another proactive step Chef Matsuo takes is featuring on his menu certain fish species that are not often served. “The Japanese are big fish consumers and traditionally ate locally caught fish, so the species varied with the region. But the 1970s saw the rise of industrial fishing groups, and these groups imposed the same species on supermarkets, like tuna, mackerel and horse mackerel or common scad. Our job as chefs is to shine a spotlight on fish that have essentially been forgotten, such as gacho or kasago.”

© Nathalie Cantacuzino

He makes a point of explaining his approach to guests, helping them understand the importance of sustainable fishing. June is the season for isaki (chicken grunt), hotate (Japanese scallop) and katsuo (skipjack tuna). For the katsuo, Hideaki Matsuo ensures they are caught by single-hook fishing called “kenken ryo”, a particularly sustainable fishing method, because only what is needed is caught. As our awareness expands, we see our sliced katsuo placed before us, seasoned with a mustard-miso sauce and garnished with shiso and spring-onion flowers. A delight for all the senses.

Text - Marion Bley