noun
koji mold; Aspergillus oryzae
A mold used in Japanese fermentation to make sake, miso, soy sauce, and other products. Scientific name Aspergillus oryzae.
See also: コウジカビ
麹菌は日本酒の醸造に欠かせない。
Koji mold is essential for brewing sake.
味噌を作
To make miso, first you make rice koji using koji mold.