For Sushi, Ike Jime Is the Sustainable Way Forward

So long, umami and omakase — it's time to make room for a new sushi buzzword destined for the margins of Japanese-American menus. It's called ike jime, and it has the potential to revolutionize much more than just your rainbow roll lunch special.

Ike jime (pronounced ee-kay jee-may) is what Andrew Tsui calls a “considered kill,” and it's been the standard practice in Japan's fisheries for hundreds of years. Tsui is the president of the Ike Jime Federation, which he founded in 2014 to establish a certification program for US fishers and to help raise the profile of the Japanese fish-handling technique outside of Japan. To harvest a fish using basic ike jime, a fisher must do two things: insert a spike into the fish's brain to render it brain dead, then bleed the fish before putting it on ice. It sounds pretty gory, but the goal of the technique is actually to cause the fish the least amount of stress possible — not necessarily out of humanitarianism, but because there are real biological and culinary consequences when an animal routed for our plates has to put up too much of a struggle in its final moments of life.

Experts Featured in This Article

Andrew Tsui is the founder and president of the Ike Jime Federation.

Kate Masury is the executive director at Eating With the Ecosystem, a Rhode Island–based seafood sustainability nonprofit.

Youji Iwakura is the head chef of omakase pop-up Youji's #WashokuRenaissance in Charlestown, MA.

Kate Masury, executive director of seafood sustainability nonprofit Eating With the Ecosystem, tells PS that conventional harvesting methods in the US are about as stress-inducing as they get: hauling up large quantities of fish and letting them suffocate to death on the deck. For those fish, the stress enzymes they produce will actually break down the quality of their meat. An ike jime brain spike, however, reduces stress and thereby the enzymatic activity, helping to preserve the quality of the fish so that it's safer — and tastier — if it's eventually going to be eaten raw.

After the fish has been spiked, the subsequent bleeding helps to purify it of bacteria, further locking in the meat quality and allowing the fish to be aged. “The smell you associate with fishy smell, that's bacteria breaking down. If you can reduce bacteria, you're increasing the shelf life,” Masury says. Because of the bacteria build-up, you're better off eating most conventionally caught fish quickly, like within a few days of the catch, and cooking it well instead of eating it raw.

Not only could conventional harvesting methods be seen as cruel, but they're also wasteful, they cheapen the overall reputation of American seafood, and they're keeping US fishers — a historically overlooked demographic — out of lucrative markets.

Before we see the widespread adoption of ike jime in US fisheries, the way we think about and value the humble fish will need to undergo a sea change.

In New England, one of the country's largest and most climate change–battered fishing hubs, ike jime is already seeping into the culture. Masury's nonprofit Eating With the Ecosystem has piloted the Rhode Island Ikejime Project in partnership with the University of Rhode Island and the Ike Jime Federation, offering trainings to chefs, fishmongers, and fishers. Together, these organizations are trying to build a regional market for ike jime–caught fish and help local fishers earn more for what they catch.

Some chefs, too, are optimistic about ike jime's potential foothold here. Chef Youji Iwakura, who runs a cult-favorite omakase pop-up, Youji's #WashokuRenaissance, out of a shared commercial kitchen in Charlestown, MA, says the US is in the midst of an ike jime “movement,” predicting that it's going to be the next big thing in Japanese-American cuisine.

But before we see the widespread adoption of ike jime in US fisheries, the way we think about and value the humble fish will need to undergo a sea change.

“I think that fish as a species holds a certain cultural place [in the US], which is effectively a glorified vegetable that does not have a central nervous system, that does not feel pain,” he tells PS. (Though he emphasizes that the Ike Jime Federation tends to avoid subjective, anthropomorphizing terms like “pain” or “suffering,” preferring to focus on the measurable, biological markers that indicate the animal's stress.)

He says the older generation that dictated existing policies around fish intake in this country have historically “had a really problematic relationship” with fish and seafood, casting it as a smelly, easy-to-spoil, pseudo-meat only suitable for deep frying or bread crumbs and butter. But all those characterizations? “That was the direct result of their handling methods,” Tsui says.

Tsui, who once worked on a tuna boat near Hawaii, says he often encounters sports anglers who have been catching striped bass their entire lives but who might never have really tasted one. “They've had rapidly decomposing and spoiling filets of striped bass in a frying pan, smothered in Walmart seasonings. But when have they ever really truly experienced the fullest expression of what that striped bass could be?”

At Youji's #WashokuRenaissance on a recent rainy evening, chef Iwakura partnered with Eating With the Ecosystem to prepare an entire omakase dinner using all locally caught fish. There was silky grouper sashimi, tender aged monkfish medallion, and perfectly chewy black sea bass sushi. Guests also slurped a delicate countneck clam miso soup, tucked into two kinds of sea urchin, and savored a juicy, butterflied deep water shrimp.

Sushi made from local fish is a rare treat in the US, because without widespread ike jime, most commercial raw fish we eat gets shipped in from elsewhere. In his own customers, Iwakura has come up against prejudice toward local fish, saying that initially when he advertised his local menu, his sales went down by a third.

People told him they're willing to pay omakase prices because the fish is “exotic” and of a different quality. But what they don't realize is that you can get the same quality of fish here in the US, cutting way down on transportation emissions and supporting local fishing economies.

Taken to its most extreme reaches, Tsui believes ike jime principles have the potential to reverse ecological and cultural damage done by our existing approach to fisheries.

Seafood, especially wild seafood, has been “systematically devalued,” he says, and so have the fisheries that harvest it, which puts marine stewardship and conservation efforts in those areas at risk. He gives a hypothetical example of black sea bass in Rhode Island: If the value of that fish keeps going down, fishers are forced to catch more of it just to break even.

“You're going to collapse the fishery, and then people can't make a livelihood, and you've lost an economy and potentially you've lost an ecosystem,” he adds. “You cannot conserve what you do not value.”

Ike jime, more than anything, is a mindset shift. “It's an active process that requires you to be deliberate and intentional,” Tsui says. “If you just turn a blind eye, you're really asking for trouble on the plate.” That “neglect,” as he calls it, has profound consequences — not just for the quality of our spicy tuna rolls, but for the future of our watery ecosystems.

Emma Glassman-Hughes (she/her) is the associate editor at PS Balance. In her seven years as a reporter, her beats have spanned the lifestyle spectrum; she's covered arts and culture for The Boston Globe, sex and relationships for Cosmopolitan, and food, climate, and farming for Ambrook Research.