What is Bodaimoto?

“Bodaimoto” is said to be Japan’s oldest method for preparing a “shubo” (yeast starter). The name Bodaimoto comes from the name of the temple “Bodaisen Shoryaku-ji” where the technique is thought to have become established. Bodaisen Shoryaku-ji played a central role in temple brewing and is where the concept of “shubo” (yeast starter) became established. It is for this reason the area is considered to be the birthplace of Japanese refined sake.


We will now explain the characteristics of the Bodaimoto preparation process and reveal the untold story of its origins.


Bodaisen Shoryaku-ji Temple played a central role in temple brewing in Nara during the Muromachi period, and the shubo that was prepared at the temple was Bodaimoto.


Beginnings of the Concept of Shubo (yeast starter)

So, what exactly is a shubo (yeast starter)? The word shubo is comprised of the kanji character “shu” which means sake and “bo” which means mother. Therefore, shubo is written “mother of sake”. The shubo is prepared in order to cultivate the yeast required for making sake. Yeasts are microorganisms that are required not only in making bread but also in producing alcohol. Cultivating the yeast involves making a mixture of steamed rice, koji and water into which yeast is added. Effectively a miniature sake brew is made in a small vessel.


The modern process of preparing the shubo is about cultivating plenty of healthy yeast in this way. Once the shubo is ready, it is increased in scale by adding more steamed rice, water and koji – in three stages (three-stage mashing). The process of brewing the shubo, first on a small scale, and then adding more ingredients in stages, is considered to be very important in making sake and one of the distinguishing characteristics of sake.


In the past, when sake was made in small vessels such as tsubo and kame jars, preparing a shubo was not essential, however, as sake began to be brewed in larger vessels, it became a necessary part of the sake making process in order to ensure a safe brew. In its original form, shubo started out as small sake brews, made in small vessels such as tsubo and kame jars, which were used to initiate the fermentation process.


Bodaisen Evolves into Bodaimoto

The “Goshu no Nikki” (of the Muromachi period), said to be Japan’s first technical book on sake brewing written by ordinary citizens, contains detailed descriptions on the brewing of Bodaisen at Shoryaku-ji Temple but makes no mention of any process involving shubo. However, 200 years after this book (in the Edo period), the brewing technique of a shubo called Bodaimoto, which is very similar to the brewing method of Bodaisen, appears in the “Domoshuzoki”, a book written by a technical expert in Itami, an advanced brewing area at that time.


Difference between Modern Shubo and Bodaimoto

The most obvious difference between the method for making Bodaimoto and shubo preparation techniques most widely used in modern sake brewing (e.g. sokujo-moto, Yamahai-moto, Kimoto) is that the Bodaimoto method involves the preparation of a lactic acidic water called “soyashimizu” beforehand which is then used later during the preparation of the shubo. This allowed for yeast to be quickly cultivated in acidic conditions provided early on. With this unique brewing technique, Bodaimoto made it possible for sake to be brewed even in summer.


Bodaimoto Brewing Process of Shoryaku-ji Temple

(1)Raw rice is soaked in water for about 2 days.

(2)Lactic acid fermentation begins and the water becomes a lactic acidic water called “soyashimizu”.

(3)The raw rice that was soaked is taken out and steamed.

(4)The soyashimizu is transferred to the shubo mashing vessel (kame jar, wooden barrel, tank, etc.)

(5)The steamed rice and rice koji are added to the mashing vessel.

(6)The shubo is left to cultivate over around 10 days to 2 weeks.