Seikyo Junmai Daiginjo Maboroshi Kurobako (720 ml)

In 1947, 4th-generation brewmaster Kiyoma Nakao invented koon toka — a high-temperature saccharification method heating koji, rice, and water to 55°C to eliminate competing bacteria before rapid cooling and lactic acid addition. The technique, now used by over 60% of Japanese breweries for daiginjo competition sakes, was designed specifically to protect Nakao's most prized asset: a proprietary apple yeast isolated from more than 2,000 candidate sources, too delicate for conventional shubo environments.

Nakao Sake Brewery draws its brewing water from the Kamo Mountains above Takehara, a coastal town on the Seto Inland Sea whose soft-water geology defines the Hiroshima kirei style — low mineral interference that allows the yeast's aromatic signature to carry without hardness or astringency. Of the 26 breweries that once operated here, only two survive.

The Maboroshi Junmai Daiginjo is built on Yamada Nishiki rice from Hyogo Prefecture, polished to Daiginjo grade, and fermented with the apple yeast under the koon toka starter protocol. Crucially, it is bottled as genshu — no water addition — amplifying the yeast's fruit-forward aromatic intensity at full fermentation ABV rather than diluting it to a standard 15–16%.

This expression was served as the Imperial Household's New Year sake for three consecutive years and was withheld from commercial sale for 26 years after its competition debut, reaching the market only in 1974 due to prohibitive sake taxes — a suppressed release history unique in the modern daiginjo category.