koji

American  

[koh-jee] / ˈkoʊ dʒi /

noun

1. a fungus, Aspergillus oryzae, used to initiate fermentation of a mixture of soybeans and wheat in the production of soy sauce.

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Etymology

Origin of koji

< Japanese kōji malt, yeast < kaudi < kaũdi < kamudati, probably equivalent to *kamu (< *kanpu mold; compare kabu, a variant outcome of the same etymon) + -dati, combining form of tati to rise

Example Sentences

We bring in the koji, and then prepare the mash in wooden vats during the winter.

From The Wall Street Journal • Apr. 15, 2026

For the last seven years, Kammerer has been working with koji mold, or Aspergillus oryzae, which is widely used in Japanese cuisine to ferment soybeans and make things like soy sauce and miso.

From Salon • Nov. 12, 2024

The CRISPR-Cas9 toolkit developed in this paper lays the foundation to easily edit koji mold and its many relatives.

From Science Daily • Mar. 14, 2024

Types: All sakes designated junmai contain only rice, water, yeast and koji, a mold that converts starch into fermentable sugars.

From New York Times • Mar. 2, 2023

Takamine, in using as ferment, koji, motu and moyashi, different forms of mould, and proposing to do entirely away with malt in the manufacture of beer and whiskey, has made a noteworthy departure.

From Inventions in the Century by Doolittle, William Henry