Aspergillus oryzae: the national bacteria of Japan, is the head chef of Japanese cuisine.
It is what Koji 麹 is.
I don't know how many of you are interested and if it is available outside Japan...
However, it may be interesting just reading for some cooking geeks like me... it is boring for most of the people though, hahaha.
Koji is produced by sprinkling koji mold spores called Moyashi (same name but not bean sprouts!) namely aspergillus oryzae onto steamed rice(or other kinds of grains or beans) to breed them and they produce more than 30 kinds of good enzymes.
Top two important enzymes that Koji produces are amylase: an enzyme works to carry out the conversion of the starch into glucose which is perceived as sweetness, and protease: an enzyme works to carry out the conversion of the protein into amino acids which is perceived as umami.
This action makes soy sauce, miso, mirin, sake, ama-zake, vinegar, tamari, etc etc...
Almost everything in Japan is made by Koji!!
I hear that the original wild aspergillus oryzae was poisonous.
Humans tamed this mold into "healthy"!
If you understand how this head chef works, you can ask to make whatever you imagine.
(You don't need to work! just wait until done. Koji works!)
Soy free miso, Soy free soy sauce, Sugar free adzuki jam, Amazake of other grains, Miso of other beans, etc etc...
Creativity is infinity.
I love playing with Koji.
Home made chickpea white miso tastes like parmigiano reggiano!
Things you should know to make Koji work.
①Koji mold sprouts at 30~35℃. grows well at 35~38℃. Dies at 40~50℃.
②Koji mold needs oxygen to live.
③Koji mold needs water to live.
④Koji mold makes protease at 25~30℃.
⑤Koji mold makes amylase at 35～40℃.
⑥Protease is the most active at 30~50℃.
⑦Amylase is the most active at 60℃.
⑧Most of enzymes are inactive under 15℃. Die at 60~80℃.
⑨Most of enzymes are active around 20~50℃. Amylase is the exception.
⑩When certain amount of salt is added, koji mold dies, but protease still works.
You may be making Ama-zake, Miso, or Shio-koji.
(Because you are reading to almost the end!)
Or doing "New creations"?
Or want to try?
Waiting for good reports of your work!
* In Japan, dry rice Koji 糀 is available in almost all regular supermarkets.
Miyako-Koji みやここうじ is the most widely available brand.
Some supermarkets carry fresh raw koji too.
I don't know how many people are using it for "New creation".
(No one around me. No one even makes regular miso.)
And the starter: koji mold spores called Moyashi are available online shops.
You can also grow koji from store bought dry rice koji, same as all the other fermantation.
