A university and a beer maker in Gunma Prefecture near Tokyo have teamed up to brew beer using the key ingredient in konnyaku, a popular Japanese food.

Gunma University and the brewery hope the new beer will help to promote the local konnyaku root plant. The prefecture is the largest grower of the plant in Japan.

The partners say they are using technology developed by the university that breaks down the dietary fibers in the roots into two types of sugar.

The team says the ingredients add a slightly bitter flavor to the beer.

Mukai Katsuyuki, Visiting Professor of Gunma University said, "I heard from farmers that konnyaku roots are not selling well. We hope the beer will trigger an increase in their sales."

A limited run of 550 bottles of the beer are on sale in the prefecture.