Sushi Train Invention: A Japanese Innovation

Have you been to a sushi train? There are colourful plates chugging along a metal track carrying food to hungry customers. These restaurants might seem like they come from the future, but the sushi-train or kaiten zushi was invented in Osaka, Japan nearly seventy years ago! **The big idea** Yoshia...

Have you been to a sushi train? There are colourful plates chugging along a metal track carrying food to hungry customers. These restaurants might seem like they come from the future, but the sushi-train or kaiten zushi was invented in Osaka, Japan nearly seventy years ago! **The big idea** Yoshiaki Shiraishi was born on Shizouka Island in 1913. As a boy, Yoshiaki dreamed of moving to the bustling mainland of Japan, where there were more opportunities for a person with big ideas. When he was older, he packed his things, borrowed a fishing boat and sailed to Osaka, the second capital city of Japan. After working in a tempura shop, Yoshiaki opened his own sushi restaurant, but couldn't find waitstaff to serve his customers. Thinking of a solution, Yoshiaki remembered a tour he had taken of a bottling factory and watching bottles being moved along a conveyor belt. If he could use this idea to serve the sushi in his restaurant, he wouldn't need as many staff. Before his idea could work, Yoshiaki had three main problems to solve: **Problem one---materials** First, Yoshiaki used wood and very thick paper for the conveyor belt, but that didn't stand up to the regular washing needed to keep it clean. Next, he tried iron, but that rusted. Finally, Yoshiaki tried stainless steel, which could be washed every day without rotting, tearing or getting rusty. It was perfect. **Problem two---corners** Next Yoshiaki had to figure out how the conveyor belt should turn corners. The plates got stuck or fell off when the corners were right angles, like a square. After seeing people holding playing cards in a fan shape, Yoshiaki realised that by using half-moon-shaped pieces of steel, just like the fan, the conveyor would contract gently around the corners. Yoshiaki was then able to build his sushi-train in a 'U' shape to fit his restaurant This shape also allowed for the largest number of customers to be seated. **Problem three---speed** The last problem was the speed of the conveyor belt. Too fast and the fish would dry out and plates could fall off. Too slow and busy customers would get annoyed waiting for their food. After lots of trial and error, Yoshiaki found the ideal to be the conveyor moving 8 centimetres per second. He also decided that the conveyor belt should move in a clockwise direction as most Japanese held their chopsticks in their right-hand so their left-hand was free to pull the plates from the sushi train. After five years of testing, Yoshiaki opened the first sushi-train restaurant in 1958. His idea was a big success, and now sushi trains are found in every continent. Yoshiaki Shiraishi found it very amusing that his little idea helped bring Japanese cuisine to the world and make sushi one of the most popular foods today.