Cedar-vat sweet potato shochu: CEDAR's third release, "EMBER"

Kedoin Distillery in Kagoshima Prefecture released “CEDAR EMBER Kurikogane” on 9 September 2026 as the third instalment in its CEDAR series of sweet potato shochu brewed in wooden vats. Sweet potato shochu (imo-jochu) is a signature spirit of Kagoshima in Kyushu, close to the southern end of Japan, and is made by fermenting sweet potatoes with koji mould and then distilling the result. The raw material this time is a variety called Kurikogane, sometimes referred to as a “phantom potato” because so few farmers grow it. The bottling sold out on 18 September, nine days after release. The distillery has announced that the next release is planned for September 2027.

A wooden-vat challenge that began in 2007

Kedoin Distillery began brewing sweet potato shochu in wooden vats in 2007. According to the distillery, there were almost no precedents for brewing sweet potato shochu in wooden vats at the time, so everything had to be worked out by trial and error. The distillery lists handmade koji, fermentation in wooden vats, distillation in wooden stills and storage in caves as its hallmarks. “CEDAR” is the English word for the tree known in Japanese as sugi, and the series takes its name from the unusual method of brewing in cedar vats. While inheriting traditional skills, the distillery aims for new flavours that only wooden vats can produce.

The “phantom potato” Kurikogane and its two faces

Kurikogane is a sweet potato whose name contains the Japanese words for “chestnut” (kuri) and “gold” (kogane). EMBER was made by brewing this potato slowly in cedar vats. The distillery explains that it can be enjoyed in two different ways depending on how it is served. On the rocks or mixed with cold water, a crisp first sip is followed by a sharp finish that lingers like a glowing ember, which is where the product name comes from. Served as “oyuwari”, with hot water, it releases a soft aroma and a gentle, chestnut-like sweetness.

Comparing wooden vat and clay pot

In the same article, the distillery also suggests tasting EMBER alongside “Koshu Tezukuri Aoshio”, which is brewed in a traditional unglazed clay pot (kame-tsubo). It is made with handmade koji and sweet potatoes from Kagoshima Prefecture, fermented in the pot and matured for more than three years. Comparing how the brewing vessel shows up in aroma and mouthfeel is a pleasure particular to sweet potato shochu.

If you want to enjoy this story in Europe, the first things to look at are the brewing vessel and the potato variety. The labels of sweet potato shochu, or an importer’s description, sometimes state the vessel used, such as wooden vat, clay pot or tank, as well as the variety of potato. EMBER itself is sold out, but the next release is scheduled for September 2027. With a sweet potato shochu you already have at home, one option is to try the same bottle on the rocks and as a slightly lukewarm oyuwari. The aroma and sweetness may come across differently depending on the temperature.