SUSHI GOES HI-TECH:
Robots Prove Adept at Shaping Rice
November 26, 2001
Sushi is known throughout the world as the quintessential Japanese food. Conveyor-belt sushi restaurants, as popular as ever in Japan, have spread as far and wide as Paris, London, Amsterdam, and New York. Some pioneering restaurants in Japan have turned to technological innovation as a means of pleasing customers and producing profits.
Rice: The Lifeblood of Sushi
Shari, the rice portion of sushi, is a slightly compressed, cylindrical bed of rice that fits snugly in a softly clenched hand. A touch of wasabi and a piece of freshly sliced fish on top rounds out a typical piece of sushi, as known and enjoyed in Japan and around the world. Great sushi is a result of the quality of the shari and the freshness of the fish. Since the beginning of sushi, shari has traditionally been prepared by hand; several years of training are usually required in order to make it properly. Recently, however, the appearance of robots that can prepare shari in place of humans has been grabbing attention.
Technology and Tradition
The quality of sushi made by robots is comparable to that achieved by veteran chefs. Sushi robots are primarily used at kaiten-zushi (conveyor-belt sushi) restaurants. These commonly feature an elliptical counter around which customers sit. A conveyor belt revolves around the perimeter of the counter, bringing forth a colorful variety of sushi, usually two or three pieces per plate. As the sushi plates pass by, customers simply reach out and select their favorites. Kaiten-zushi tend to be less expensive than traditional sushi restaurants, where the chef takes the customers' orders and directly serves the sushi across the counter.
The sushi conveyor belt, a Japanese invention, has also undergone some hi-tech innovations. A new type of conveyor belt invented by Ishino Works Corp. (site in Japanese only) features a transparent plastic cover along its whole length to help preserve the freshness of the sushi and protect it from dust. Kita Nihon Kako Corp. makes a conveyor belt that has no chains or holes, making it easy to clean and more sanitary. Japan Crescent Co. has developed a more powerful conveyor belt that can circulate larger plates of food, such as tempura and desserts, in addition to the smaller plates of sushi.
Interest from Abroad
Sushi robots were first introduced in around 1981 but were initially kept tucked away in the back kitchens and out of sight, due to concern that customers would lose their appetites if they saw shari being shaped by a metal contraption. Recently, however, a new type designed in the shape of a traditional rice tub has been introduced. Shari is shaped inside the tub by a screw-shaped blade. Once a piece of shari is removed by the sushi chef, the next piece is made right away.
The kaiten-zushi business model, which offers customers healthy sushi at a reasonable cost, has begun spreading to other Asian countries and to the West. It takes many years to become a good sushi chef, however, including mastering how to shape shari, so achieving high quality in countries that are new to sushi is difficult. Sushi robots may be the answer to this problem, as they could enable sushi lovers anywhere to enjoy shari of broadly the same quality found in conveyor-belt sushi restaurants in Japan. This may help to explain why inquiries from restaurant owners overseas about these new sushi robots have been on the increase over the last couple years.