Sake is brewed, and its production is therefore reminiscent of that of beer. Its alcohol content, however, is about 15% which, in addition to its various flavour profiles, makes it most closely comparable to wine. In spite of these comparisons to both wine and beer, Sake production is unique in that it entails the simultaneous conversion of starch to sugar and the alcoholic fermentation of said sugar (beer, on the other hand, is brewed from pre-saccharized malt).
The heart of Sake production lies in the conversion of rice starch into fermentable sugar. Even the first Sake produced over 2000 years ago went through the same starch-to-sugar conversion as modern Sake with the small caveat that back then it wasn’t Koji mold which was responsible for this biochemical ignition, but rather an enzyme within the saliva of young priestesses who would chew boiled rice to kickstart fermentation. In modern times, Koji is applied as a fine powder to steamed rice to create, under precise temperatures, a converted and fully fermentable form of rice. The Koji-inoculated rice is then mixed with freshly steamed rice and water to form the mash. The ensuing fermentation process is typically carried out at gentle, low temperatures to allow for the development of elegant and balanced flavour profiles.
Sake is traditionally brewed in the winter to take advantage of the naturally low temperatures. Most brewery workers fulfill a dual function of working outdoors in an agricultural capacity in the summer whilst focusing on brewing activities in the winter. The master brewer is called Toji and is responsible for conducting the symphony of activities within the brewery and managing the workers who carry out such activities. Historically, a Toji would independently negotiate a contract with a brewery and then take it upon himself to build a brewery team consisting of local villagers. Occasionally, the Toji and his team would move to an entirely different brewery in pursuit of better pay.
Toji were often in the habit of working far from home, sometimes being away from their families for up to a half a year at a time. These tough working conditions were required to achieve the organisational skills, production know-how, and years of experience necessary to become a master brewer. Today, the sons and daughters of brewery owners typically study brewing science at university to achieve many of those same skills before returning home to work at the family brewery and eventually take over the role of Toji Brewmaster.