When San Francisco chef James Corwell was teaching the Navy how to cook in Japan, he took them on a trip to the Tsukiji fish market in Tokyo.
Two warehouses sat at the center of the market, each the size of a football field. Every morning at 5:30 a.m., the warehouse fills with tuna from all over the world. And by 10:30 a.m., each of the tuna are auctioned off and shipped again to other parts of the globe.
“They do that every day of the week, week after week, month after month, year after year,” Corwell said at the James Beard Foundation’s “Rethinking the Future of Food” conference in New York City on October 19. “For me seeing that type of harvest going on — and that’s really the only word I can put to it, it’s an outright harvest of this animal — was mind blowing. That was my epiphany that something needed to happen.”
And by “something,” Corwell means finding a way to satisfy the tuna-loving taste buds of restaurant goers without contributing to the ever-growing problem of overfishing.
According to the National Oceanic and Atmospheric Administration, several species of tuna are severely overfished. Pacific Bluefin Tuna, which is prized among sushi-lovers for its distinctive fatty, red flesh, has been declining for more than a decade. The population of mature adult Pacific Bluefin Tuna are currently at only 4% of the population they would be at if they had never been fished.
The problem, though, is that tuna is an extremely popular dish. And many chefs want to put it on their menus, Corwell said, because every consumer wants to eat tuna.
“How do you reconcile that?” Corwell said. “And that’s something I still struggle with today.”
So Corwell turned to another ingredient that has that similar savoury taste profile to tuna, but which isn’t in danger of going extinct.
“Japanese cuisine uses a lot of umami, and tomatoes at one point were processed for their umami quality in the production of monosodium glutamate (MSG),” Corwell said. “I put two and two together, and fortunately tuna was red like a tomato — and voila! — we have tomato sushi.”
“It was tasty — thick and fatty, just like real tuna, with a savoury taste that only betrayed hints of tomato-ness,” FastCompany wrote. “I would mistake it for tuna in a line-up, but probably not after putting it in my mouth.”
Corwell simulates the tuna experience by skinning the tomato and then by vacuum sealing it in an air-tight plastic bag with organic gluten-free tamari, vinegar, natural herbs, and spices. Then he drops it into a hot water bath for about an hour — a step in a high-end French cooking technique called sous-vide.
This technique firms up the tomato and gives it that quintessential meaty taste.
“We’re eating so much tuna, that if we don’t stop, there won’t be any tuna in a few years,” Brian Doyle, co-owner of Tomato Sushi, said in a Kickstarter video.
Tomato sushi is currently only available in its packaged form at Rainbow Grocery in San Francisco, but Corwell and his team are doing pilot tastings in the San Francisco Bay Area.
Check out more about it here.
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