29 Nov 2016

What is Koji (麹) to Japanese?

Ancient wisdom of preserving food descended from 2,000 years ago.
The Art of Fermentation: Learning how to make koji, for brewing sake
Knowledge to utilize koji 麹 ('qu' in Chinese) cultivated molds or fungi from boiled grains had been developed in Asian countries, while yiest (kobo酵母) or maltz (bakuga麦芽) grown from fruits or wheat in the West.

koji (Aspergillus oryzae) grown by cultivating molds on boiled grains, produces various enzyme, such as amylases, proteases, and it is very versatile, used for multiple purposes and consists of the basis of  Japanese cuisine "washoku".

There are three types of koji, kome 米 koji (rice koji), mugi 麦 koji (wheat koji) and mame 豆 koji (bean koji) .
Rice koji is used for brewing sake 酒,  'amaze' 甘酒(fermented rice poriage) and  'miso' 味噌(fermented soy paste, 'jiang 醤' in Chinese), wheat koji is mainly for making 'shoyu' 醤油 soy source and bean koji is for making 'natto' 納豆(soy nuggets).
 
The Art of Fermentation: Learning how to make koji, for brewing sake
misoThe Art of Fermentation: Learning how to make koji, for brewing sake
koji for making soy sourceThe Art of Fermentation: Learning how to make koji, for brewing sake
rice ball koji in south-east asiaThe Art of Fermentation: Learning how to make koji, for brewing sake
Red rice mold used for making red rice wine and tofu-you

How to make koji?

major source for introducing japanese brewing in foreign languages are as follows.
 
R.W. Atkinson "brewing in Japan" published in 1878
Korshelt "über sake dass alkoholische vertrank der japaner" in 1985

the step is simple;  soak and steam rice, inoculate and incubate tane koji 種麹 (starter).
It is also possible to cultivate starter from rice grain in the paddy fields, but nowadays, usually bought from tane koji factory. 
 The Art of Fermentation: Learning how to make koji, for brewing sake
molded ice grain 'inadama稲玉'  is inoculated in boiled rice

Making koji is something like baby-sitting

Keeping temperature is very important when making koji; 32-36 degree Celsius.
lower than that, enzyme of koji will be deactivated, and when higher than that, it will also be dying.
 
It takes around 3 days to be ready, and needs to be paid attention every 4 hours. It needs to make warmer, or cooler when heated too much.

Step by Step...

1. mushi 蒸し, boiling rice

The first step is the most important above all, said a touji (brewer),

The Art of Fermentation: Learning how to make koji, for brewing sake
 The Art of Fermentation: Learning how to make koji, for brewing sake
Wheat mold
2. tane kiri 種切 and tsutsumikomi 包込, rolling 

Inoculate starter, tane koji 

The following morning, koji is penetrating the rice.
3 days later....
 The Art of Fermentation: Learning how to make koji, for brewing sake
3.karashi 枯らし, drying koji
This is the last moment of fermentation process.
make ditch on koji, shaped spiral, three lines, or wavy line to dry it up.
the shape of the ditch depends on the brewery, said a brewer, showing us beautifully drown ditch on koji, which seemed like 'karesansui枯山水', dry garden in zen temple, the art of fermentation!. 
 
The Art of Fermentation: Learning how to make koji, for brewing sake
4. shimai 仕舞, dancing koji
 
Shimai means the end in japanese, and 'mai' also stands for dancing.
spreading white colored koji mold is something like dancing, indeed.
 
The Art of Fermentation: Learning how to make koji, for brewing sake

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