Shio Koji (塩麹, 塩糀) is a mix of salt, water and rice koji, and it’s a natural seasoning used to marinate, tenderize, and enhance the umami, or richness (one of the five basic tastes), in foods. It’s a live food that is rich in enzymes that break down the starches and proteins in food into sugars and amino acids.
Rice koji (米こうじ, 米糀, 米麹) is steamed rice that has been treated with koji mold spores (Aspergillus oryzae, koji-kin 麹菌, or koji starter). You may wonder why we make rice moldy on purpose. Koji is a specific strain of mold that has been cultured over the centuries. Mostlikely, you’ve already eaten it. Koji has been the key ingredient to make miso, soy sauce, sake, mirin, rice vinegar, amazake, shochu, and shio koji.
Use shio koji to marinade meats, make pickles, or just use as a salt substitute. Shio koji is very versatile and can be used in any kind of cooking (See Shio Koji recipes)!
To get a step-by-step recipe for making shio koji at home, click here.