The park is owned and operated by Kanefuku, one of Japan's largest producers of mentaiko.
The facility processes tons of Alaska pollock roe daily, sourced primarily from waters near Hokkaido and Russia.
The mascot character 'Tarapiyo' is featured throughout the park's branding and merchandise.
Freshly made, non-frozen mentaiko—a product rarely available in standard grocery stores—is the primary specialty sold in the retail section.
The factory floor utilizes specific low-temperature climate control technology to maintain the quality of the raw roe during processing.
Mentai Park Oarai is a specialized facility dedicated to the production and consumption of mentaiko (spiced pollock roe), operated by the manufacturer Kanehisa. The site features an observation gallery where visitors can view the factory's automated cleaning, seasoning, and packaging processes through large glass windows. A central exhibition area, known as 'Tarapiyo Kids Park,' provides interactive educational displays about the life cycle of pollock and the history of mentaiko. The facility includes a dedicated food court serving exclusive products such as mentaiko rice balls, mentaiko soft-serve ice cream, and steamed buns. A large shop sells an extensive variety of fresh and processed pollock roe products, including limited-edition items available only at this location. As of June 2026, the facility continues to operate as a major culinary destination in the Ibaraki Prefecture coastal region. It is designed to accommodate families and large groups with extensive indoor facilities.
The large, colorful mascot statue near the main entrance.
Sample the fresh, raw mentaiko at the tasting station in the gift shop before purchasing.
Check the production schedule at the entrance to witness peak activity on the factory floor.
Visit the food court early in the day to avoid long queues for the popular mentaiko onigiri.
Do not attempt to photograph the factory floor using flash, as it can be distracting to employees and the automated systems.
Open daily, though the factory production lines may occasionally pause for maintenance or holidays.
