Kochi was formerly known as Tosa (土佐).
The local specialty is katsuo no tataki, bonito quickly grilled under high heat so the surface is cooked but the inside is still raw.
17 sake breweries in Kochi make Tosa Space Sake (土佐宇宙酒 Tosa uchūshu), prepared with yeast that was taken into space for ten days and back aboard a Soyuz rocket in 2005, so be sure to sample some for a taste experience that is out of this world. Alternatively, try to track down some space yoghurt (宇宙を旅したヨーグルト Uchū wo tabi shita yōguruto, lit. "The yogurt that travelled in space"), prepared from the same yeast.