Koji, scientifically known as Aspergillus Orzae, is a mold fungi. Just like mushrooms, it begins its life as a spore. These spores produce tiny filaments called hyphae, which forms a tight network of mycelium as it matures. Towards the peak of maturity, instead of maturing into a fruiting body like a mushroom, koji matures into a microbial mat comprised of tasty mold. Koji is traditionally grown on rice, barley and soybeans but can be grown on almost all substrates that contain protein and or starch.
At the peak of it’s maturity, koji produces two main types of powerful enzymes, proteases and amylases. Proteases break down proteins and amalyses break down starches. These enzymes are great at breaking down these larger protein and starch molecules into delicious amino acids and sugars.