Kumamoto Students Develop Fertilizers from Shochu Remnants

Science Society Technology

Kumamoto, Aug. 17 (Jiji Press)--Students in Kumamoto have developed a low-cost method to culture photosynthetic bacteria, which work as fertilizer, using distillation remnants of "shochu" spirits.

The developers, led by Aoi Koga, 24, a second-grader of Sojo University's Graduate School of Engineering in the southwestern Japan city, hope to help farmers cut their use of chemicals and distillers save money for disposing of the liquid remnants called "shochu kasu."

In 2016, Koga produced a liqueur targeting young women in collaboration with a distiller of rice-based Kumajochu shochu, a specialty of the Hitoyoshi Kuma area in Kumamoto Prefecture.

At that time, she realized that disposing of shochu kasu left after the distillation of mash made from fermented rice costs a total of 400 million yen a year at 28 distillers.

Launching research in April the same year, Koga found that the distillation remnants contain rich citric acid suitable for culturing photosynthetic bacteria. She and other students kept trying to find how to culture the bacteria with shochu kasu while receiving advice from Prof. Hitoshi Miyasaka, their mentor and a photosynthetic bacteria expert.

[Copyright The Jiji Press, Ltd.]

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