Appetizers / International / Side Dish

Natto Recipe : fermented soybeans

Fermented soybeans, also referred to as Natto, is a traditional staple in Japanese cuisine. This natto recipe is easy, quick, and incredibly healthy. Bonus points – you can make this probiotic superfood natto recipe in your own instant pot!

If you aren’t familiar what natto is but you’re curious about this natto recipe, then here’s a brief introduction to natto. Natto is a traditional Japanese food staple that gets a bad rep.

For those of you that haven’t tried natto, natto has a mucinous texture and viscous consistency, and a pungent flavor that most non-Japanese can’t tolerate. In fact, despite existing in American obscurity for awhile, natto emerged into the spotlight after becoming notoriously mentioned on the Anthony Bourdain show. He said:

The Japanese love natto, an unbelievably foul, rank, slimy,
glutenous, and stringy goop of fermented soybeans. It’s the Vegemite
of Japan, dearly loved by everyone there, for reasons no outsider can
understand. If the taste wasn’t bad enough, there’s the texture. There’s just no way to
eat the stuff. I dug in my chopsticks and dragged a small bit to my
mouth. Viscous long strands of mucouslike material followed, leaving
numerous ugly and unmanageable strands running from my lips to the
bowl. I tried severing the strands with my chopsticks, but to no
avail. I tried rolling them around my sticks like recalcitrant angel
hair pasta. I tried slurping them in. But there was no way. I sat
there, these horrible looking strings extending from mouth to table
like a spider’s web, doing my best to choke them down…

Still with us?!

Hey, Anthony! Wait a second, we like our natto! Okay, okay. I suppose I should have started with a more flattering description of natto because natto is a super probiotic food, and though it requires a specific palate, it’s really good!

What Anthony forgot to mention is how amazing natto is.

Natto is fermented soybeans. It’s considered a super food that’s rich in probiotics and is considered to have multiple health benefits. In Japan, it’s known to lower cholesterol and have heart and artery benefits. Not only that, but you can find natto accompanying most dishes in Japan. There is Natto-maki, gunkan-maki, natto fried rice, natto with daikon, and many other Japanese meals that include natto. Yum.

For those of you have you read this far and are curious enough to attempt this natto recipe, proceed!

The ingredients and equipment.

  • Natto soybeans. We purchase our natto soybeans directly from Laura’s Soy Beans website, and we’ve been really happy with the quality. Natto soybeans can be used for making natto or for sprouting.
  • Filtered water. You’ll want to use filtered water each time the instructions call for water. Soybeans absorb a lot of water, so you’ll want to use highly filtered, clean water.
  • Mother natto. Mother natto is where you’ll get the natto spores from. Since natto is fermented, you’ll need something to act as your SCOBY. In creating kombucha, a SCOBY is a symbiotic culture of bacteria and yeast. I don’t know exactly if the term SCOBY can be applied to natto, but mother natto is the same concept: the original culture of bacteria and yeast. For us, we get our mother natto from pre-made natto. We find our natto in the Japanese grocery store, typically in the frozen section. It comes in packets of four or five, and we will use less than one packet to act as our mother natto.
  • Instantpot! This is where the magic happens. You can grab yours, here.
  • Strainer. Any strainer will work. We love our Oxo Strainer.
  • Cupcake tin for freezing. Silicone cupcake pans make freezing and storing natto a snap.
  • Scooper. I LOVE my scooper and use it for everything: pancakes, batter, rice balls, and now, natto! I recently grabbed the Oxo scooper, and it is, by far, my favorite. The quality feels much more sturdy than my other scoopers, and I love that the measurement size is listed inside. For natto, we use the medium scooper.

The process.

The process is extremely simple and is pretty much fool-proof.

First, take your natto soybeans and soak them in filtered water overnight. It doesn’t matter how much water you use, but we use a 1:3 ratio. You’ll just want to make sure the natto beans are covered in enough water. In the morning, drain the natto and toss into your instant pot.

Again, cover your natto beans with filtered water. Use enough water to ensure the beans are covered with water. Then, turn your Instantpot on high for 20-23 minutes. If you prefer a softer natto, then cook for 23 minutes; however, if you like your natto more firm, adjust the time to 20 minutes.

While your natto is cooking in the instant pot, take your mother natto and mix it with an equal amount of warm water. I use about 1.5 tablespoons of mother natto and 1.5 tablespoons of warm water. You’ll get a really slimy, unappetizing concoction – this is my least favorite part about making natto. Place it out of sight so you don’t have to look at it again until you need to use it.

Once your instant pot if finished, do a quick release and then drain the natto. Quickly put the hot natto back into the instant pot and toss in the mother natto and water mixture. Quickly stir the mother natto in with the cooked natto, ensuring that mother natto and baby natto are happily mixed together.

Fermentation and storage!

Next, fermentation! Leave the natto in the instant pot to ferment, and cover the top off with a papertowel. A paper towel allows air to circulate through, ensuring that fermentation happens. Plus, the paper towel collects the condensation and helps prevent water from getting all over the counter.

After 24 hours of the natto fermenting, it’s ready!! However, natto stink is real. If the smell is too overwhelming, you can place the natto in the fridge for a few days for the smell to abate. If the smell doesn’t bother you, then you can eat as is! Or, you can freeze it in the muffin tin.

For us, freezing in the muffin tin is the best way. We’re able to freeze a large batch into individual portions, and save them until we need them.

And that’s it!! It’s a relatively easy process. Tried this method?! Let us know what you think!

Natto Recipe

Fermented Soybeans


  • Pressure Cooker
  • Strainer


  • 2 Tbsp Mother natto * 1/3 of a natto packet
  • 1 cup soy beans for natto * smaller beans for natto (we recommend
  • 3 cups Filtered water + enough to cover for boiling


  • Soak your natto beans overnight in water. We use a ratio of approximately 1 cup of beans to 3 cups of water.
  • After soaking overnight, drain the beans and place in the Instantpot.
  • Cover natto beans with filtered water – enough to cover the beans.
  • Set Instantpot on high. Cook between 20-25 minutes, depending on how firm you want your bean. We do 23 minutes, for medium firm.
  • While this is cooking, prep your mother natto. Mix 2 tablespoons of mother natto with 2 tablespoons of warm water to create a slimy natto mixture. Set aside.
  • Once your Instantpot has run the cycle, quick release. Drain natto and immediately return hot beans back to Instantpot.
  • Working quickly, add the mother natto mixture to the hot beans. Stir to coat beans with the mother natto mixture.
  • Place a towel or something breathable on top of the pot; you'll want air to circulate through to aid in the fermentation process. Leave like this overnight, or for 24 hours on yogurt mode.
  • Once your natto has fermented, you can serve serve or freeze to use at a later date.


If the smell of the natto is too strong immediately after fermenting, you can leave the natto mixture in the fridge for 24 hours before freezing or serving.  This sometimes helps the smell dissipate. 

Looking for other recipes?! Try these!

Indian Mac and Cheese Cooking Review
Natural Pink Frosting Recipe
Easy Chorizo Pasta Recipe

1 Comment

  • Patricia
    April 18, 2023 at 7:41 am

    Bacteria subtilis is the fermenting organism. Using chickpeas results in a higher vitamin k2 content.


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