TOKYO - If you have ever bought supermarket sushi, you may know the taste trauma that hit Kazuhiro Shimura one night.
But the "disappointing" tuna sparked an idea: he would develop an artificial intelligence (AI) system to make sure your sashimi is always delicious.
Shimura, a director at advertising firm Dentsu Group's Future Creative Centre, came up with the concept for "Tuna Scope" AI as he chewed his raw dish while watching a television show on fish merchants who spend a decade mastering the skill of selecting high-quality tuna for sushi restaurants.
Using a deep learning algorithm to crunch through grading data from merchants, Tuna Scope has now evolved into a smartphone app.
Clients can download and use it anywhere, creating "a unified grading standard" for an industry that relies on local know-how, said Shimura, who is working with Japanese trading company Sojitz Corp to promote his technology.
"That means people can be sure they are getting delicious tuna," Shimura told Reuters at fish merchant Misaki Megumi Suisan, which ships AI-certified tuna overseas.
The highest quality fish - which can each weigh around 300kg - have sold for more than US$3 million (S$4.2 million) in past tuna auctions.
According to the Organisation for the Promotion of Responsible Tuna Fisheries, around two million tonnes of tuna is consumed around the world annually, of which Japan accounts for a quarter.
Since the start of the coronavirus pandemic, fish merchants from the Maldives, Spain, the United States, Taiwan and elsewhere have contacted Shimura about Tuna Scope because travel curbs mean they cannot visit suppliers to check tuna quality, he said.
At Misaki Megumi near Tokyo, one of the merchant's buyers Shingo Ishii held a smartphone with Tuna Scope over a tray of tuna tail sections on a metal tray as other workers used industrial saws to cut up frozen tuna shipped from around the world. The AI delivered a result within a few seconds.
"I think this will become a common tool over the next 10 to 20 years," said Ishii, holding the smartphone over one of the tail sections.
Ishii admitted to mixed feelings about a technology that could make his job easier, but threatened to make a skill passed down through generations obsolete.
"To be frank, I think I can still beat the AI," he said.