To prep the ingredients, break the dried rice malt, boil the water, and completely dissolve the salt in the boiled water.
When the boiled water cools to 60 ℃, add the rice malt, cover with a lid, and keep at room temperature for 2-3 hours.
The rice grains will have absorbed the water somewhat, but should still be dry on the inside. Stir thoroughly once a day, and keep stored at room temperature until it ferments.
After 3 days, it will be very soft, but you should still be able to clearly see the individual rice grains. Let it ferment a bit longer.
After 6 days, the rice grains should be dissolved, and when you open the lid, you should be able to smell the rice and a subtle fermented scent. It's ready to use. Store in the refrigerator.
Story Behind this Recipe
Shio-koji has become a standard seasoning ingredient in our home. Since I use it to make many dishes, I added the recipe for it here. Since our children don't like salty food, I prepare it with less salt than usual.
Since I believe using better quality ingredients result in better flavor, I used natural salt from Ogasawara island. The key is to maintain a consistent fermenting temperature (60 ℃). It's also important to rely on your sight and smell to judge when it is ready when stirring it daily.