The secret to the high-tech future of sushi lies in an unremarkable building in the alleys of Osaka.
Inside, empty plastic cups and plates decorated with crumpled wet paper – to recreate the weight and texture of scallops – move along a conveyor belt.
On the one hand, hidden behind a plastic screen, technicians monitor data on computer screens, the specificity of their work is considered inaccessible to Observer and a small group of journalists granted rare access to a development “studio” owned by Sushiro, a leading force in Japan’s multimillion-dollar sushi train industry.
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This is where developers are gradually improving the restaurant chain’s ability to deliver plates of freshly made sushi to tables at lightning speed and stay one step ahead of the competition in a sector estimated at 740 billion yen (about £4 billion).
“In the past, diners took what they wanted from a universal conveyor belt, but nowadays most people want to order their favorite sushi,” said Masato Sugihara, deputy IT manager at Sushiro’s parent company, Food and Life.
The studio is a replica of a typical Sushiro restaurant. “Here we can ensure that the delivery system is working properly and send the right order to the right customer as quickly as possible,” he said. “We may make improvements, such as improving the guest interface of the online menu, that we cannot make in real time in our restaurants.
“It’s not top secret, but our neighbors have no idea what we’re doing here.”
Holy Grail of rotating sushi (or kaitenzushi) is perfect, contactless, low-cost dining – a trend accelerated by the pandemic and labor shortage that will leave Japan with an estimated 6.4 million workforce shortage by 2030.
Near the secret Sushiro facility, staff prepare for lunch at the chain’s outlet in the Namba district, one of approximately 4,000 kaitenzushi restaurants all over Japan.
Guests at the 236-seat restaurant use a touch panel to choose from 150 items, from sushi and fried chicken to coffee and cake. Their bill is calculated automatically and payment is made via a vending machine at the exit, where customers who have ordered take-out online take their orders from a bank of lockers.
It’s a far cry from the traditional sushi bar of the popular imagination, where stern-looking, long-serving chefs place plates of meticulously prepared seafood on wooden counters.
But Nobuo Yonekawa, an expert on kaitenzushisays the industry is losing its appeal in the face of rising prices and competition from other types of affordable cuisine. “Customer numbers are declining, and to get them back, the industry needs to think about technology differently,” said Yonekawa, who wrote a book on the subject.
Although there is no shortage of high-end establishments, sushi consumption has undergone a revolution from the very beginning kaitenzushi an outlet opened in Osaka in 1958. Purists may protest, but automation has made it possible to take sushi out of the high-end and expensive sphere of Sukiyabashi Jiro and others and turn it into a fast food that rivals burgers and fried chicken.
The mass consumption of sushi was only possible thanks to advancing technology, coupled with a cultural shift away from gastronomic exclusivity.
At Sushiro’s Namba Amza, each plate comes with a label that lets you know in real time which sushi is selling well. The labels are read by sensors located under the conveyor belt, so that the correct order is sent to each table. Plates that have not been picked up, and those in the second free-for-all lane where guests can help themselves, are automatically removed after 350 meters.
“We use AI to analyze which dishes are popular at each restaurant and order fish accordingly,” said Yutaka Sakaguchi, director of IT at Food and Life. “In the beginning kaitenzushi, the chefs had no clear idea what people wanted. They had to act instinctively.
“This allows us to reduce food waste, but it also allows managers to predict with some certainty what sushi to prepare and how many workers might be needed on certain days. It also affects the weather… like what foods are more popular when it’s warm and sunny. Before this system came along, we were wasting a lot of food.”
In the back of the kitchen, a robot massages small blocks of rice at about 3,600 per hour. “It’s impossible for a chef to do it so quickly,” said Yurika Murai of Sushiro’s public relations department. Each block is identical and traditionally served at skin temperature.
“The machine is programmed to make the sushi look like it was molded by human hands,” added Murai. “These aren’t just soulless blocks of rice.” Further down the production line, another device wraps the rice pieces in nori seaweed for chefs to finish and place on conveyor belts.
As a rule, the sushi should be in front of the customer no later than three minutes after placing the order. The yellow and red lights come on to alert the chefs that the order has not yet come out.
“Our main challenge is to capture during peak lunch and dinner times which fish are most frequently ordered,” said Sugihara. “You can’t just flood a conveyor belt with lots of plates, so we count the number of customers and the average number of plates ordered at certain times of the day, which allows us to anticipate demand during busy and non-busy periods. “
But there are some tasks that are still the domain of humans, such as cutting a fish and placing it on rice. “Cleaning plates and tables is also difficult for machines,” said Sakaguchi. “However, the lack of manpower makes it increasingly difficult to find new employees, so we need more automation. Perhaps the answer lies in more robots, but we haven’t gotten there yet.”
Sushiro CEO Koichi Mizutome dismissed suggestions that high-tech sushi has stripped the dish, which has existed in a recognizably modern form for about 200 years, of culture and artistry.
“Our world is based on automation and achieving exactly the same level of service in all our restaurants where people can eat sushi at an affordable price,” he said. “Other [world] is based on the individual approach of chefs who have undergone years of training. I think these two worlds of sushi can coexist.”