Recipes from Miso/Koji Event

  • Chicken marinated in shio-koji (gf)
  • Koji-aged steak (gf)
  • Tofu with miso+shio-koji sauce and shoyu koji sauce(vg)
  • Roasted vegetables with sweet tahini and amazake sauce (vg, gf)
  • Koji zuke raw vegetables (vg, gf)
  • Roasted Rice Balls with shoyu-koji (vg)
  • Miso Ramen by Gomen Ramen
  • Beer and Wine

This was the menu for our reception at the Lace Mill in Kingston on October 14, 2018. The reception followed a miso-making workshop by Koichiro Kawasaki of Marukawa Miso from Fukui, Japan.

Koji is rice inoculated with koji culture (Aspergillus oryzae) and is a major ingredient in production of sake and miso. But it has also garnered much attention in the last 10 years as a stand alone seasoning or in a marinade foam called shio-koji.

Shio Koji

Mix 100g of fresh koji or 80g of dry koji) with 35g of salt. Transfer to a yogurt container or a glass jar. Fill with non-chlorinated water to just above the koji. Stir. Keep at room temperature away from sunlight. Stir everyday. Ferment for one to two weeks. It is ready to use when the rice grains have softened and start to lose shape, and has a sweet aroma. It can be used as is or blended till smooth.

Shoyu Koji

Skip the salt and use soy sauce in place of water.


Heat 300cc of water to 60ºc. Mix in 250g of fresh koji (or 200g of dry koji with additional 50cc of water). Transfer to yogurt maker or a thermo jar. Ferment the mix at around 60ºc for 8 hours.

Chicken Marinated in Shio-koji

Simply marinate chicken in shio-koji (a scant teaspoon per boneless breast, or a thigh) from 4 to 24 hours. It is high in salt, use sparingly. Fry, grill, or bake, at lower temperature than usual. Koji is very easy to burn, so be careful.

Koji-aged Steak

Salt steak as usual. Cover completely with powdered dry koji. Place on a rack on a tray. Keep in refrigerator uncovered for 2 to 3 days, turning once or twice. Cook as desired, but being careful not to burn the surface.

Tofu with Koji Sauce

Mix shio koji and miso paste to your taste. Cube or slice firm tofu. Fry with a little oil until pale brown. Sprinkle with sake and the mixture of shio koji and miso. Stir to coat. Variation: use blended shoyu koji.

Roasted Vegetables with Tahini-Amazake Sauce

Coat vegetables (we used kabocha squash and green beans) in oil and roast in oven. Blend tahini and Amazake to a desired consistency. Serve the sauce on side.

Koji-pickled Vegetables

For Japanese turnips, use the mixture of shio-koji and mix. Cut off the tops and cut large ones in half. Coat the turnings in the shio-koji and miso mixture, keep in a ziploc bag overnight, turning a few times.

Separate and wash Napa cabbage leaves. Slice into thin strips. add several thin strips of konbu(kelp) if available. Coat with shio-koji. Place in a bowl, cover with plastic wrap. Place a small plate on top and weight it down with a bottled water or heavy pot. Ready in 24 to 48 hours.

Grilled Rice Balls with Shoyu Koji

Make rice balls using Japanese rich and a small amount of salt. Make them flat. Grill on a griddle or frying pan until pale brown. Brush with blended shoyu-koji, grill until brown.

Miso Ramen

Go to Kickstarter, sponsor Gomen Ramen’s campaign, and visit their restaurant after they open!


Miso and Koji Party at the Lace Mill

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On a sunny Sunday in October, we hosted a special culinary event—a miso-making workshop and koji tasting reception with Koichiro Kawasaki, master miso-maker from Fukui, Japan.

Koji is one of the major ingredients for sake, miso, and other quintessential Japanese treasures. It is the starter used for the fermentation and brewing process, made by inoculating rice with koji culture.

Fresh koji, showing long threads of the culture

Although koji has been around for hundreds of years, it was not commonly used as a stand-alone seasoning until recently. For the last decade or so, a marinade made by further fermenting koji with salt and water (shio-koji) became extremely popular in Japan.

In the meantime, a curious thing happened here in the U.S. A handful of chefs and foodies have started experimenting with dried koji as a rub for steaks, claiming it gives the meat a deep flavor resembling that of dry-aged steak. A quick search would turn out many videos and articles relating to this technique.

It is fascinating to witness this culinary evolution of koji in these two cultures, highlighting the significance of the term used to express both the microbial realm and human achievements.

In celebration of this cultural exchange, we reached out to Marukawa Miso, a family-owned and operated miso maker founded in 1914. Their store-manager, Koichiro Kawasaki, is an energetic 35-year-old with passion for well-being of the global citizens and the environment. He came to the Hudson Valley to build a bridge between his network of conscientious food producers of Japan—and us.

Watch the video of the miso-making workshop, read a detailed instruction on how to make miso at home, and check out the recipes from our menu.

We are immensely grateful to our sponsors:



How to Make Miso at Home

This page has been translated from the website of Marukawa Miso. All photos are from their site, used with permission.


Yield: about 6kg (13lb) of miso

[Translator’s note: the sweetness of miso is determined by the ratio of koji (starch/sugar) to beans (protein)—the larger the amount of koji, the sweeter the resulting miso.]

Sweet miso: soybeans 1100g, koji 2600g, salt 750g

Medium sweet: soybeans 1300g, koji 2000g, salt 800g

Dry miso: soybeans 1500g, koji 1800g, salt 800g

[The above figures for koji is for fresh koji. If using dry koji, decrease the amount by 20%—1800 grams instead of 2000, for example. Then add the same amount of water (200cc in the example) to koji to reconstitute it.]

This is the original recipe that has been passed down through generations at Marukawa Miso. It has a larger amount of koji compared to other commercial products, resulting in sweeter miso.

Step 1: Soybeans—the Key Ingredient

The most important step in miso-making is cooking of beans. How the beans are cooked determines the color, flavor, fragrance, and texture of the finished miso.

What to Look For in Soybeans

  • Choose large beans
  • Beans from current year (readily absorb water)
  • Beans with good flavor

The better the cooked beans taste, the better the miso will be.

Wash beans thoroughly and soak in water three times the weight of the beans for 18 hours. It is imperative that the beans are fully hydrated. Check by splitting one bean in half. If the center is still hard (left in photo), soak longer.

Step 2: Cook soybeans

Discard water (beans are surprisingly dirty—if cooked in soaked water, the color turns slightly grayish), fill the pot with fresh water until the beans are just covered, turn on heat to high.

When the water first comes to boil, add a cupful of cold water. After it returns to boil again, turn the heat down to simmer and cook for 3 hours, adding water as needed so the beans are always covered.

If using pressure cooker, cook for 20 minutes.

Beans are fully cooked when you can crush a bean between a thumb and pinky finger, or at around 500g when pressed against a scale.

Don’t be concerned if you see skins of the beans floating in water. They can be mashed with the beans. But it may indicate over cooking—keep at a simmer to prevent this.

Step 3: Mash beans

Drain the beans, reserving some cooking liquid. Process the beans while hot until smooth, or mash them in a mortar and pestle or in a plastic bag with a glass bottle or rolling pin. This takes time when making a large batch.

Step 4: Mix ingredients

Mix rice koji evenly with salt in a big bowl or tub. Stir into mashed beans, mixing them all evenly. If using fresh koji and the beans are hydrated and cooked fully, no additional water should be necessary. If using dry koji, you could add some cooking water. Finished paste should have the feel of earlobe. Be careful not to add too much water in this step. This could cause mold to develop.

Step 5: Pack

Roll the paste into balls. Smash or press into a container. This could be a food grade plastic pail, ceramic crock, or a wooden tub. Press each ball firmly to eliminate air bubbles. Smooth the surface, place a parchment disk, paper, or plastic film directly on the miso, seal the edge, cover with a plate or wooden disk and weight it down with a stone or a large water bottle.

Step 6: Store

Cover with a towel, a lid with an airlock, or a loose lid. Store in a dark place with as little temperature fluctuation as possible. At room temperature, miso will be ready in 10 months to a year. Miso is forgiving with temperature. If cool, it’ll take longer to ferment, if hot, shorter. But do not check the miso frequently. Every time it touches air, you’d be inviting mold.

Ideally, keep the miso at around 10ºc for 3-4 months, at around 20ºc for 3-4 months, then at 30ºc for 2 months.

At Marukawa, we believe that miso is at its peak flavor at 10 months to a year, but it can be aged longer. Move to refrigerator to slow down fermentation.

About Mold

It’s almost inevitable that you’ll find mold on the surface of miso. Do not be alarmed. Simply scrape it off. To prevent excess mold growth, seal the surface and do not let miso be exposed to air (but it also has to breathe so don’t cover it with air-tight lid). At Marukawa, we use special washi, handmade by a national treasure Ichibei Iwano. It is also important to weight down the miso sufficiently. This will bring up excess liquid to top, preventing the surface from coming in contact with air. This liquid is tamari, considered as liquid gold by many.