A sweet aroma envelops a neighborhood in Saito, Miyazaki Prefecture, whenever a tanker truck delivers dregs from distilling strong “shochu” spirits made with sweet potatoes.
The destination of the trucks is a brand-new recycling facility that turns sediment resulting from the production of shochu into ethanol to be used as an alternative to gasoline. Brazil mixes ethanol made from sugar cane with gasoline to fuel automobiles, while the United States uses corn.
“The sediment of ‘imo’ (sweet potato) shochu has a sweet fragrance,” said Yosuke Tajiri, managing director of the Saito recycling cooperative. The cooperative’s facility, which started operating in May, stands on high ground about 40 minutes by car from the city of Miyazaki.
It is one of a growing number of installations being built by shochu distillers to cope with a ban on dumping residues in the ocean that took effect in April.
When shochu is made from sweet potatoes, a brown fluid about 90 percent water is left over that contains sweet potato fiber. In the past, the bulk of the residue, about twice the volume of the shochu produced, was dumped into the sea.
Five shochu makers established the cooperative in April, including the Kagura distillery in the town of Takachiho that produces Tenson Korin (grandson of the sun goddess).
The residue from the process is separated. Solid substances are dried for use as a feed material for cows and pigs. The fluid is condensed into ethanol with a volume of 80 percent and is used as an auxiliary fuel at the facility.
Tajiri said the construction cost of the facility came to about ¥1.4 billion, adding that the expense could force some of the member companies of the co-op to raise the prices of their products.
The Kirishima Shuzo (distillery) in Miyakonojo, producer of Kirishima shochu, raised shochu prices starting late last month, partly to cover the costs of building its own facility to process the dregs.
Because the recycling facility in Saito is producing ethanol from plant residue, some are hoping it will be able to produce biofuel. Fuel blends of up to 99.5 percent ethanol are in use in Brazil and the U.S.