Vermicular | Journal | Fermentation with the Musui–Kamado

Fermentation with the Musui–Kamado

The Art of Fermentation in Japanese Culture

The subtle artistry of Japanese fermentation unfolds as a nuanced tale, delicately intertwining tradition with culinary heritage. Sublime flavors such as miso, koji, amazake, natto, and soy sauce emerge from a profound respect for this timeless technique, honed over centuries to infuse simplicity with complexity and depth. Yet, in our modern, fast-paced world, the patient process of fermentation may seem like a relic of the past—until now.

With the Musui–Kamado’s precision temperature control, it’s now possible to revive the fermentation process in your kitchen with contemporary ease and efficiency.

Crafting the Perfect Bacterial Habitat

The Kamado's temperature control, with increments as precise as 1ºF within the range of 90-200ºF, and its uniform heat distribution achieved through three-dimensional induction heating, create an optimal environment for cultivating thriving healthy bacteria. When paired with the Musui cast iron’s excellent heat retention, the Musui–Kamado ensures a consistent temperature throughout the cooking process. This scrupulous temperature management nurtures the highest caliber of fermentation, eliminating the need for the traditional, painstaking waiting period to cultivate robust and healthy bacterial cultures.

Wellness from Within

Within the elegant simplicity of fermented foods lies an arsenal of benefits that accompany each bite. These microbiotic elements contribute to supporting your inner ecosystem, assisting the immune system, promoting skin health, revitalizing hair, and aiding digestion. Fermentation is not just about flavor; it adds a touch of well-being to daily life, infusing resilience and vitality.

Maintaining a robust immune system is as essential as ever. Probiotic-rich fermentation turns foods into living antioxidants, helping fortify the body's defenses and reduce the severity of common infections, potentially lowering the risk of chronic diseases, from cancer to cardiovascular maladies.

Additionally, our gut, a delicate ecosystem, thrives on balance, and fermented foods play a crucial role in maintaining a healthy microbiome. By restoring or preserving biodiversity, these foods contribute to mental health, metabolic function, and overall vitality. Notably, incorporating fermented foods into your diet improves digestive health, easing conditions like irritable bowel syndrome, enhancing nutrient absorption, and facilitating weight management. Embrace the simplicity of fermentation, for it not only enriches your diet but also enhances the vitality of your everyday life.

Fermentation with the Ease of the Musui–Kamado

With the Musui–Kamado, the array of fermented delights expands—enjoy the sweet, earthy miso, the subtle sweet and salty notes of shio koji, and the silky comfort of amazake. Each creation reflects the blend of nature and nurture. The Musui–Kamado is your ideal companion in delving into the world of fermented foods, enabling you to craft varieties in your own home in significantly less time than traditional methods.

White Miso

A staple of Japanese cuisine, miso is a protein-rich paste made from fermented soybeans. Using the Kamado's precision temperature control, craft miso to glaze fish and vegetables, marinate steak, and much more.

150 g dried soybeans
200 g rice koji (malted rice)
3 ½ tablespoons (30 g) kosher salt


  1. In a large bowl, soak soybeans for 12 hours. Split a bean to check if water has absorbed through. Transfer drained beans to the pot, immerse in fresh water and boil uncovered on [MED] heat for 10 minutes.
  2. When water boils, skim any foam from surface. Cover, and simmer over [EXT LOW] for 150 minutes.
  3. Once beans are soft enough, drain using a strainer (keep broth). Use a blender to puree beans. Gradually add broth to the point where the puree is firm enough to be rolled into a ball with your hands.
  4. Separate rice koji into individual grains. Combine with salt and mix. Add bean paste to mixture and smooth surface. Cover and ferment over [WARM 140°F] for 480 minutes (8 hours). Lightly stir every 2 hours.


  • Miso can be used to glaze fish and vegetables or to marinate steak. It can also be stirred into soup or whisked into salad dressings and can be refrigerated for up to 6 months.


Amazake is a comforting and nutritious beverage that whispers tradition with every silky sip. This non-alcoholic, gently sweet drink is loaded with essential amino acids and an array of Vitamin B complexes making it a drink that fortifies as much as it pleases. When crafted with the Musui–Kamado, Amazake takes on a new life, featuring live enzymes and a boost of probiotics, outshining its market counterparts. Vegan, probiotic, gluten-free, and with no added sugars, Amazake from the Musui–Kamado is a balanced and health-conscious choice for all.

1 rice cup (180ml) white rice
3¾ cups (900 ml) water
200 g rice koji (malted rice)


  1. Add rinsed rice into the pot after thoroughly draining. Add in water and select [RICE COOKING] mode, [WHT], [PORR] (Porridge). Set the amount to [1.0] rice cups and cook uncovered.
  2. Once the alarm goes off, remove the pot from the Kamado and let it cool down to room temperature.
  3. Separate rice koji into individual grains and add them to the cooked rice. Stir once, then flatten the rice mixture.
  4. Cover and ferment over [WARM 140ºF] for 480 min (8 hours). Lightly stir every 2 hours.


  • You may divide it with either hot water, oat milk, or soy milk when drinking.

Shio Koji

A fermented Japanese seasoning and condiment used to marinate, tenderize and intensify umami, shio koji can be easily made at home with just three ingredients and the Kamado's precision cooking.

200 g rice koji (malted rice)
⅓ cup (45 g) kosher salt
1 ⅔ cups (400 ml) water


  1. Separate rice koji into individual grains in the pot. Combine with salt and mix well.
  2. Add in water and stir. Cover and ferment over [WARM 140°F] for 360 minutes (6 hours). Lightly stir every 60 minutes.


  • Shio koji has been used in Japan for centuries as an all-purpose seasoning and condiment. The live enzymes contained in shio koji bring out the sweetness by transforming starches into sugar. They are also known to break down proteins in foods not only enhancing umami but also tenderizing meat and fish.
  • Use shio koji to marinate meats, make pickles, or use it as a salt substitute. It might taste salty at the beginning, but it will gradually become mild from the fermentation. It can be refrigerated for up to 3 months.

Soy Sauce Koji

Soy sauce koji (shoyu koji) is a double-fermented food product crafted from rice koji (rice malt) and soy sauce, boasting higher nutrient content compared to shio koji. It enriches the umami essence of soy sauce components, commonly used as a topping for sashimi or vegetables, or enjoyed in small portions with rice dishes.

200 g rice koji (malted rice)
250 ml soy sauce
100 ml water


  1. Separate rice koji into individual grains in the pot.
  2. Add soy sauce and water in the pot; mix well and smooth the surface.
  3. Cover and ferment over [WARM 140°F] for 240 minutes (4 hours). Lightly stir every 60 minutes.


  • Soy sauce koji is milder in taste and richer in umami when compared to regular soy sauce. It is a natural umami enhancer and tenderizer and can be used as a seasoning, dressing, sauce, marinade, or dip.
  • It can be refrigerated for up to 3 months.

Incorporate Koji into Your Cooking