Shio koji is a natural seasoning used to marinate, tenderize, and enhance the umami, or richness in foods. Known to be an all-purpose seasoning, shio koji can be the multi-tasking seasoning in your kitchen. Shio Koji can be simply poured onto meat or fish as a marinade or added as a sauce or finishing touch. It can also be used in place of salt by substituting two teaspoons of shio koji for every teaspoon of salt.