Japan's secret to soup stock supremacy
I originally wrote this article for The Japan Times. It appears in the Saturday, Dec. 16, 2017, issue. Go to the link: https://www.japantimes.co.jp/life/2017/12/16/food/hokkaidos-unique-konbu-dials-umami-12/#.WjwGA7aZOwQ. In the above photo, Kazuaki Ida, left, head of the konbu division of the Rausu Fisheries Cooperative Association, and Makoto Mikami, talk about Ida’s recent harvest of konbu while visiting the No Borders Café in Rausu.
RAUSU, Japan — Fisherman Kazuaki Ida entered No Borders Cafe in Rausu just as we were finishing cups of hot coffee on a rainy Hokkaido afternoon. He held giant, flat-leaved stalks that scraped against each other like hard plastic, garnering appreciative “ahs” of recognition among the café’s customers. As a first-time Hokkaido visitor and relative newcomer to authentic Japanese cuisine, I remained ignorant. What were these things and why was everyone so excited?
Turns out we were seeing the product of a lengthy process that converts this seaweed called konbu into a much-sought-after delicacy used to flavor soup stocks and enhance Japanese cuisine. Konbu is a mainstay of Japanese cuisine, and not only were we in the epicenter of konbu production, but we also were meeting one its masters of the harvest.
Hokkaido produces some 90 percent of all konbu; high-end restaurants the world over covet its quality. The cold waters and nutrients that flow through the Sea of Okhotsk are responsible for konbu’s superior flavor. Ida, 65, lean and weathered from decades in the elements, has been harvesting konbu with his family since he was a boy. As head of the konbu division of the Rausu Fisheries Cooperative Association, he is the local expert when it comes to this unassuming sea product that holds such importance in Japanese cuisine.
“Of course, Hokkaido’s konbu is the best in Japan,” Ida said. The reasons are many, he added – the cold water, the rich land and the winter sea ice – all contribute to its superiority.
“And Rausu konbu is the best among all,” he added.
Ida is quite passionate about his product, but he is also part scientist, as he explained. The level of unami, a taste sensation unique to Japanese cuisine, is how one numerically measures the quality of a dish, and soup stocks, or dashi, are the starting point. The very best restaurants and chefs seek the highest unami rating possible.
Most konbus, Ida said, have an unami level of 8. To create a truly excellent dashi, the unami must reach level 12. So, chefs add an ingredient called bonito to their stock. Bonito contributes inosine acid to the konbu, thus elevating the stock to the desired unami rating of 12.
“But the stock taken from Rausu konbu records 12 level of umami without inosine acid,” Ida said, meaning dashi can be made with Rausu konbu alone.
Naoko Goto is a naturalist and guide in Rausu and she said visitors to the area are surprised to learn about konbu’s vital role in Japanese cuisine. She began offering tours during the konbu harvest, so they could better understand its relevance.
“We study the history of konbu and the culture concerning konbu,” Goto said. She also tries to impart on visitors how the fishery supports the commercial fishing economy in Rausu, a community of fewer than 6,000 people, who depend upon the sea for their livelihoods.
Ida, one of those few permitted to harvest konbu, says the process has not changed over the years. There is a short, 30-day harvest window and a time-consuming 23-step process to collect, dry and market the konbu.
“It’s manually harvested by one fisherman boarding on a small boat,” he says. Using a long rod with a pronged tip, the fisherman drags the sea floor to twist, and then pluck, each strand of seaweed by its roots.
Ida said the konbu is located using a depth-viewfinder to see below sea level where the weed grows, anywhere from 1 to 10 meters deep.
“It is not difficult (to find),” he said, “but it’s hard work.”