Akumochizake (灰持酒)

Akumochizake or akumochishu is a type of Japanese sake manufactured by adding charcoal to the fermented unrefined sake.

History and method of manufacture
The original akumochizake was kuroki (a black sake) which was a type of sake brewed since the Heian Period for offering to the gods, and this was brewed by adding rice and water to malted rice and fermenting before adding charcoal made from grasses or trees. The modern akumochizake basically continues the tradition using the same ingredients and method of brewing.

The addition of charcoal neutralizes the acidity and in fact makes the sake alkaline. This prevents the growth of bacteria responsible for decay. Moreover, the amino acid which is a component of the sake reacts with sugar, gradually forming a red tinge and creating a distinct flavor.

Adding charcoal to control the reproduction of bacteria is the origin of the term akumochizake (which incorporates the character for charcoal) and in comparison the common sake brewed since the Edo Period was heated during manufacture in order to kill the bacteria and is therefore called 'Himochizake' (which incorporates the character for fire).

Improvements have been made to the method of brewing akumochizake and it continues to be brewed particularly in western Japan, and while brewing was interuppted for a while due to restrictions on the supply of raw materials during wartime, brewing was subsequently revived.

Nowdays, while it is of course drunk as a beverage, it is also often used as a seasoning sake instead of mirin (sweet cooking sake) as it has a unique sweetness and flavor. It is called by different names in the different regions in which it is brewed.

Akazake (Red sake)
Akazake is an akumochizake brewed in Kumamoto Prefecture.

Manufacture of this was protected by the Kumamoto domain from the Edo Period and continued to be brewed even after refined sake production entered the Prefecture around the time of the Meiji Restoration and Seinan War.

The method of brewing is to add mochi rice to the ingredients, reduce the amount of water to half, ferment, and in the final stage add malted barley and ferment further, then add charcoal just before refining.

Main uses of akazake
In old days it was always partaken of at ceremonial functions and even nowadays it is often used as a spiced sake drunk at New Year.

Jizake
Jizake is an akumochizake mainly produced in Kagoshima Prefecture.

Since olden times this region has mainly produced shochu, a distilled liquor, and Jizake is the one Japanese sake that is still brewed. As a result, among akumochizake, jizake is the one most similar to refined sake.

The method of brewing is almost the same as for brewing refined sake however shochu and charcoal are added just before refining.

Main uses of Jizake
Jizake is often used instead of vinegar in the local speciality sakezushi (a rice dish flavored with sake and mixed with vegetables and seafood)..

Jidenshu (sake)
Jidenshu is a type of sake called akumochizake which is manufactured in Shimane Prefecture.

For a long while after the War it was no longer made however local volunteers and sake brewers joined forces to revive the production of Jidenshu in 1990 as a cooking sake.

It is manufactured by adding rice malt which has been fermented for a long time to mochi rice and fermenting with half the usual amount of water and adding charcoal a few days before refining the sake. It is the most rich or full-bodied akumochizake.

Main uses of Jidenshu
It is used for seasoning or glazing local dishes or products made from mashed fish.

Liquor Tax Act
Akumochizake is classified as 'other liquor' under Japan's Liquor Tax Act however it is considered a 'liquor designated as a type of sake similar to mirin' in Article 3-21 of the Liquor Tax Act and is subject to the same reduced tax rate as mirin which is 20,000 yen per kiloliter. Prior to the revision of the Liquor Tax Act in 2006, it was designated 'other sake (1)' and considered a type of sake similar in properties to mirin and not classified as refined sake or powdered sake.