One of the bad things about going to a kaiten sushi bar (conveyer belt sushi) is to see some of the plates going round and round… and round and the fish just getting sad and soggy. It must be hard for the sushi chefs to keep track of which pieces to remove from the belt at all times - serving good, fresh fish is key, but economy probably comes into play as well and you want to throw away as little food as possible.

To always be able to know that the sushi that is being offered is fresh, some Japanese restaurants are attaching a chip on the sushi plate that tells the computer when a certain piece of food has travelled more than 350 meters. It is then automatically taken off the belt. This is a Japanese video about how they do it at this kaiten sushi bar. Here pretty much everything is automated, and no real sushi chefs are required…