This special type of koji is one of the ‘black kojis’ traditionally used to make Shochu, a distilled beverage. This koji is widely used by Noma and praised in their ‘Noma Guide to Fermentation’.
A. luchuensis / A. awamori (Noma’s favorite)
Koji is the mold that can do anything: miso, soy sauce, shoyu, shio koji, amazake, black bean sauce, sake, doungjun, they all owe their taste to the fungus Aspergillus oryzae. This all-rounder can also be used, for example, to perform cool experiments with the fermentation of meat or even dairy.
About A. luchuensis / A. awamori
Aspergillus luchuensis or Aspergillus awamori is a special type of koji. It is one of the ‘black kojis’ traditionally used to make Shochu, a distilled beverage.
This koji variant is widely used by Noma and praised in their ‘Noma Guide to Fermentation’. From the book:
“[…] the taste is remarkable, reminiscent of green apple and lemons. We were very happy with Noma when we came across this special form, because the citric acid it produces contrasts sharply with the umami-rich taste of koji. ”
What is the difference between A. luchuensis and A awamori
There is none, it’s a different name for the same mold variant. Other names are A. kawachii, or A. acidus. The variant is also very similar to A. niger and A. tubingensis. Morphologically, they are all identical.
This koji is easily overgrown by it’s cousin A. oryzae (ordinary koji), so make sure that you prevent cross-contamination by working cleanly.
- At least 5 grams
- Enough for around 5 kilos of rice / grain / soybeans
- Grows best on barley
- Ingredients: rice, Aspergillus Luchuensis fungus (koji)
- Origin: Japan
- Storage instructions: shelf life at least 6 months in the refrigerator, more than a year in the freezer.
Keep in mind that this koji prefers a slightly lower temperatures than normal koji: 28 ° C instead of 30 °
How to make koji-kin
- 300 g white rice, preferably not pre-cooked
- 0,25 g (about 1/4 tsp) koji-kin starter culture (check your packaging, different types of koji have different strenghts)
- Rinse the rice until the rinse water remains clear. Let it drain for 15 minutes.
- Steam the rice for about 45 minutes. That works better than cooking it. Cooked rice quickly becomes wet and mushy when moldy, which prevents the fungus from doing its job properly. The rice should look glassy and feel soft and a little rubbery when you bite it.
- Let cool to room temperature.
- Grind up the black koji grains for better dispertion of the mold
- Mix the koji kin with the rice and let it ferment for 48 hours in a warm humid place 25 to 35 ˚C. Check regularly. Make sure to avoid condensation dripping onto the rice.
- During this period, mix a few times with a clean fork. The fungus needs oxigen.
- The rice will be completely covered in a greyish mold after fermentation. Though keep in mind that different koji variants have different colors.