The reason why sea urchin in Hokkaido is more delicious than sea urchin from elsewhere is the abundance and freshness of sustenance such as "Rishiri kelp" and "Hosome kelp" exist on the market as luxury products.
Murasaki Uni Purple Sea Urchin, perhaps is the most common Uni found Japan with its main season is just like Bafun Uni during the Summer/early Fall.
How does it taste like compared to other Uni? Murasaki Uni is mustard yellow in color and has a clean, mildly sweet taste.
Kita Murasaki Uni is known as Japan's top quality Uni, with its being extremely plumb and large in size (around the size of your thumb) so it is much larger than any of its other Japanese counterparts and it is a lot creamier and sweeter with a light of texture that virtually melts in your mouth.
Rishiri Island, a small island off Japan's northernmost point, is well-known "Uni Heaven" with its Rishiri Uni often referred to as "Jewel of the Ocean". During peak season, almost 90% of Gokujo Uni (grade AAA) originate from this area and is one of the most sought-after items by Michelin Star restaurants worldwide.