History of Koji - Grains and/or Soybeans Enrobed with a Mold Culture (300 BCE to 2021)
William Shurtleff, Akiko AoyagiISBN: 978-10948436-56-4
Publication Date: 2021 Oct. 27
Number of References in Bibliography: 1885
Earliest Reference: 300 BCE
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What is koji?
Koji is a culture prepared by growing either Aspergillus
oryzae or Monascus purpureus mold on cooked grains and/
or soybeans in a warm, humid place. Koji serves as a source
of enzymes that break down (or hydrolyze / digest / split)
natural plant constituents into simpler compounds when
making miso, soy sauce, sake, amazake, and other fermented
foods. Its fragrant white (or red) mycelium, which looks
somewhat like the surface of a tennis ball, has a delightful
aroma resembling that of mushrooms.
Koji can be divided into two basic types, depending on
the type mold used. Most koji is made using Aspergillus
oryzae (pronounced ass-per-JIL-us oh-RAI-zee). Red rice
koji is made using Monascus purpureus; it is called beni
koji in Japan and hong qu in China; both these terms mean
“red koji.” Red rice koji is used primarily as a natural food
coloring and as a natural preservative.
Kôji is a Japanese word now widely used in the Western
world and non-Chinese speaking countries in the scientifi c
and popular literature on fermented foods, Japanese foods,
and natural foods. Koji is written with the exact same
character in China and Japan.