Watch Japan's Top Inventions Season 4 Episode 6 Online

The fascinating stories and secrets behind hit Japanese products, plus parts and machines that boast the top share of niche markets. In the first half of the program, we cover the secrets behind the development of sushi robots, which automatically grip and mold rice, and have helped spread sushi around the world. In the second half of the program, we introduce refractometers, which instantly display the sugar content of fruit when a few drops of fruit juice are added.