Dec 17, 2018

OniRobot faces off against long-Established restaurant “ONIGIRI ASAKUSA YADOROKU” to make the dream rice ball!

Game Changer Catapult

OniRobot faces off against long-Established restaurant “ONIGIRI ASAKUSA YADOROKU” to make the dream rice ball!

The Japanese onigiri (rice ball) looks set to become a global business through the OniRobot, an onigiri-making robot that successfully made it past the second round of the Game Changer Catapult business contest.

Going global with onigiri to cope with the declining rice consumption in Japan

Did you know that the consumption of rice in Japan is steadily decreasing? Demand for rice was 9.5 million tons in 1996, yet by 2016 had fallen over 20% to 7.5 million.* Because rice is the core element of Japanese food, this trend suggests a serious threat to traditional cuisine. If domestic demand alone isn't enough, what about getting people in other countries to try out the taste of Japanese rice? Faced with the question of how best to introduce it to people who have never tried it before, the answer seems to be onigiri.

A significant step toward making this possible is the development of a robot able to reproduce the extremely difficult technique of squeezing the rice ball into shape. It incorporates pressure feedback controls based on a 3D shaping hand that exerts strength from five directions.

1_OniRobotの試作機_Prorotype of OniRobot.JPG

The project to take onigiri global relies on more than just the robot. The complete solution will include a communication app to ensure healthy, tasty, and easy to make rice balls, along with a system for ensuring efficient operation inside a restaurant.

2_OniRobotのプロトタイプ_OniRobot Prototype.JPG

After the success at SXSW, the OniRobot squares off against a respectable opponent

At South by Southwest 2018 (SXSW) held in Austin, Texas in March this year, the OniRobot served 800 rice balls. People who had never tried an onigiri before said "I enjoyed the taste!" "Tasty!" "how cool the robot itself is!". This success shows that delicious food knows no borders, and that rice and rice balls certainly have the potential to be a hit outside Japan.

3_SXSWに出展したOniRobot_OniRobot at SXSW_2018.JPGAt SXSW: Many people tried out their first onigiri.

However, how will the OniRobot fare with consumers in its native land Japan? To find out, we approached the Onigiri Society, Japan's official organization for this traditional food. They were surprised at how good it tasted. "All right, let's test it against a pro," they suggested. The professional chef they had in mind was none other than Yosuke Miura, the third-generation owner of "ONIGIRI ASAKUSA YADOROKU", the oldest onigiri restaurant in Tokyo. Rice balls made by his experienced hands are exactly what the OniRobot team is aiming for! This incredible contest took place on November 28, 2018, at the restaurant itself in Tokyo.

Professional onigiri chef of ONIGIRI ASAKUSA YADOROKU vs. OniRobot, at SEIBU Ikebukuro.

The rice used in the contest was a variety called Milky Queen from Aizu, recommended by the Sogo & Seibu department store as the best for making onigiri. First, the rice is cooked so that the individual grains stand while the flavor contains the unique combination of puffiness and sweetness.

4_ミルキークイーン_Milky Queen_.JPG

Yosuke Miura, Yadoroku's owner chef, made a sudden appearance just as the wonderful aroma of cooking rice began to fill the venue. Dressed casually in a down jacket and knit cap, he didn't look like the third-generation master of a restaurant with a 64-year history.

5_おにぎり浅草宿六の三浦洋介氏_Yosuke Miura from Yadoroku_.JPGYosuke Miura of Onigiri Asakusa Yadoroku, and Saori Kako, project leader of the OniRobot team

After a slight sense of anticlimax, the two sides began to work out the details of the contest.

Kako: "So, how should we cook the rice?"

Miura: "I'll leave it up to you."

Kako: "And the salt ...?"

Miura: "Just use ours."

Oh, really? His casual nature only increased the nervousness of the OniRobot team, while hinting at his confidence in his own abilities.

At 11:30 a.m., the guests, who had made reservations in advance, began to gather. Mr. Katsunori Seki of the Onigiri Society made a short speech to lead off the contest. "Our society is active with the aim of bringing a proper rice culture to the world. The goal of this event is not to find who can make the better product, but instead to show that there are different ways to enjoy onigiri."

6_おにぎり協会の関さん_Mr.Seki from Onigiri Society.JPGMr. Seki of the Onigiri Society

Miura of Yadoroku started.

"Squeeze it so the outside is firm, but the inside is puffy."

"The salt should come up to the first joint of your index finger."

"The most important point is that the rice should be hot."

"The rice should cover half your palm."

"Once the rice is in your hand, spread it flat and build a firm outside wall."

"Spread it, shape it from the outside, then turn it three times while squeezing it."

"Onigiri must have a triangular shape, so make sure to turn it three times - practice this every day!"

"Now you can open your own onigiri restaurant."

In this familiar voice, Miura casually seemed to give away his trade secrets. The customers seemed unsure about getting all this information

8_おにぎりを握る三浦氏_Mr. Miura making Onigiri.JPG

7_おにぎりを握る三浦氏_Mr. Miura making Onigiri.JPG

Next came the OniRobot's turn. The ideal onigiri is firm on the outside and puffy on the inside, just as for the Yadoroku restaurant.

To achieve this, hot rice spread flat is first squeezed from five sides after which the pressure is suddenly relaxed, repeating this cycle a total of five times. This rhythm of pressure and release results in a firm outside shell, while leaving air in the middle. The OniRobot also demonstrated how pressure patterns could result in onigiri squeezed into a very tight ball, or also into a soft mound of rice that quickly falls apart. Following in the same vein as Miura, the robot showed its patented squeezing techniques.

9_OniRobotを紹介する加古_Saori showing OniRobot.JPG

Next, the trial version of the OniRobot app, to serve as the brain of a pro chef, made its appearance. We tried ordering the desired characteristics, such as the texture, puffiness, softness, size (big, medium, or small), and type of filling (just salt in this case).

10_OniRobotのアプリ_OniRobot app.JPGThis is a prototype of the OniRobot app.

11_アプリを確認する参加者の皆さま_Attendees trying OniRobot app.JPGThe customers tried it out.

Finally, each customer was served two onigiri to taste and compare. It was a tense time waiting to see their reactions. Finally, we began to hear comments from them.

"They're both yummy!"

"The amount of salt in the Yadoroku onigiri is perfect!"

"You can easily taste the firm outside and puffy inside of the OniRobot one."

"Yadoroku's is soft and fluffy. The OniRobot needs to make it a little softer."

The final result was that half the people said the onigiri's were around the same level. The OniRobot put up a good fight!

The result was a draw, but it was still a reminder of what a chef has that a robot doesn't

We got a better reaction than expected from the customers, as well as many voices of support, giving us confidence in the robot's technique. But at the same time, we realized that there was more to it than this. Being human is still an advantage, in the form of Miura's own presence as a master chef and his ability to flexibly deal with customers. In fact, while we observe Miura's performance, we could see how he was adjusting what he did to show the differences with the OniRobot's technique while looking at the reactions of the customers. He could then get them to try and compare the rice balls to show them the difference, further enhancing the customers' enjoyment. This is an important point. Only another human is able to read the feelings of the people eating the food, to fine-tune it to what they want, and bring them satisfaction.

The other point we learned is that there is no right or wrong answer when it comes to onigiri. Normally we assume that professionals follow their own path without compromise, but this doesn't necessarily apply to Miura. As long as you use hot rice and turn it three times while squeezing it evenly, you can make onigiri with any rice or salt, showing the same techniques outside the restaurant or even in another country. There's no right or wrong answer about which side of the seaweed sheet to use either. "The smooth side and the rough side both have different tastes, so instead of saying one is correct, you should try and enjoy both." This sense of freedom was a real revelation to us. The key point about onigiri is that they can be freely enjoyed anywhere and at any time.

The important thing is to simply and casually communicate that. Actually, there was a highly surprising announcement the day before this contest. MICHELIN Guide Tokyo 2019 Selection has included an entry for ONIGIRI ASAKUSA YADOROKU and has added onigiri as a new genre. Miura's philosophy of making sure the customer enjoys his or her meal has clearly been communicated and made an impact around the world, leading to this success. Yadoroku emphasizes simplicity that speaks beyond the barriers of language, and a casual atmosphere welcoming new guests despite being such a long-established restaurant mentioned in the Michelin Guide. The restaurant has lasted these past 64 years merely by keeping true to its techniques in addition to staying close to the hearts of its customers. This made us keenly realize the essential importance of this Yadoroku hospitality in bringing onigiri to the world.

Well, that was our experience at the rice ball contest. In terms of taste, OniRobot did quite well, but in all honesty, it was somewhat of a letdown to realize that by looking at Miura himself, regardless of how far technology evolves, there is still a level beyond that. Nevertheless, thinking about what professional chefs have that the robot does not may have supplied an answer for the direction of app's development, which is currently under question. What the OniRobot needs is a sense of hospitality to help bring joy and satisfaction to its customers. By incorporating this spirit into the services provided and the ordering app, we hope to speed up our progress toward achieving a solution to allow people around the world to enjoy eating rice, and to cope with the lack of professional chefs in Japan.

12_イベントの様子_At event venue.JPGScene at the event venue

We hope to get comments from people far and wide in order to incorporate their thoughts into our work and make the OniRobot even better in the future.

13_OniRobotプロジェクトリーダーの加古とGCCの池野_Saori from OniRobot and Ikeno from GCC.JPGKako Saori, project leader of OniRobot, and Naoya Ikeno from Game Changer Catapult

*Source: Basic Guidelines on Supply, Demand, and Pricing of Rice, by the Ministry of Agriculture, Forestry and Fisheries.


If you ever have the chance, we definitely recommend visiting Onigiri Asakusa Yadoroku, the oldest onigiri restaurant in Tokyo. The texture of the rice, the flavor of the seaweed, and the balance of the flavorings comprise the ideal that our OniRobot team is aiming for. People around the world will enjoy the experience of sitting at the counter and talking to the restaurant's owner chef, Yosuke Miura.

We are convinced that people the world over will come to realize that onigiri is a part of Japanese cuisine that everyone can enjoy. Yadoroku intends to maintain its same style even after its addition to the Michelin Guide, so be prepared to queue up to get in. Make sure to get there before they run out of rice!

Special Thanks: Onigiri Society


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