Shoyu Koji vs. Shio Koji in Umami, Recipe, Usage

A new type of seasoning called Shio Koji (塩麹) became a hot topic in Japan several years ago.

It is a versatile, lumpy white paste made from three ingredients, Koji or malted rice, salt, water, fermented, and aged.

Shio Koji is now a popular seasoning used to marinate or tenderize food, such as meat and fish, or enhance their umami taste.

Specific usage includes the following.

Pork Slices Marinated in Shio Koji

  • Marinating a slice of meat in Shio Koji for over a couple of hours makes the food tender. Also, its umami increases thanks to the enzyme produced by aspergillus contained in the seasoning.
  • Vegetables pickled in Shio Koji become tasty Asazuke pickles.
  • A combination of Shio Koji and sesame oil makes a good pair with vegetable salads.

Shoyu Koji (醤油麹)

In addition to Shio Koji, another fermented seasoning called Shoyu Koji (醤油麹) has become popular recently.

Although the making only calls for malted rice and soy sauce, fewer ingredients than Shio Koji, Shoyu Koji is superior in umami.


Shoyu Koji and Shio Koji

Shoyu Koji has a savorier taste than Shio Koji because the main ingredient, Shoyu (醤油: soy sauce), uses soybeans.

Specifically, Shoyu Koji has more than ten times the umami component of glutamine compared to Shio Koji.


Nonetheless, the preparation of Shoyu Koji takes less time than average Shio Koji recipes.

Based on this article on, the making of the former seasoning is like this.

Shoyu Koji

Ingredient Ratio
Soy Sauce (Shoyu) 1
Malted Rice (Koji) 1
  1. Put Koji in Tupperware and add the same amount of Shoyu or soy sauce.
  2. Give the mixture a good stir once a day to feed air and enhance the fermentation for one week or so.
  • If the malted rice soaks up the liquid on the second day, add some soy sauce again until immersed.
  • Keep the mixture at room temperature over the process.

After making it, you can store the Shoyu Koji in the fridge for three months.


Cold Tofu with Shoyu KojiImage:

Shoyu Koji and Shio Koji are both multi-purpose seasonings.

While the latter salt-based seasoning can be a good marinade, the former soy sauce-flavored one can be a good substitute for soy sauce.


  • As a condiment for grilled fish, use Shoyu Koji in place of soy sauce.
  • As with soy sauce, the Shoyu-based seasoning goes perfectly on tofu and natto.
  • Shoyu Koji pairs well with mayonnaise and creates a delicious dip.
  • Shoyu Koji (2 parts) mixed with vinegar (2), olive oil (2), and honey (1) turns into a tasty dressing.


Hi, I'm Tomo, a Japanese blogger living in Niigata Prefecture, Japan. For the purpose of enriching your life, I would like to introduce things about Japan on this blog, especially unique Japanese products, cooking recipes, cultures, and facts and trivia.

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