Homemade Fermented Natto

Natto is simply soybeans that are fermented that are a staple in traditional Japanese cuisine. You only need two ingredients for our recipe, dried soybeans, and water.

The process of making natto takes quite a few hours to make, however, the machine does most of the work. You know you’ve made a great batch of natto when stirring it brings out gooey strands. Our recipe doesn’t call for any natto starter as it creates its own beneficial bacteria following our method.

Making your own natto at home is extremely cost-effective. Buying premade natto in the freezer section at most Asian grocery stores can be costly for small packages. You’re getting healthy doses of fermented soybeans at a fraction of the cost of buying natto pre-made. Score!

 

Key features and tips

A fair warning, that we are fermenting soybeans so it will be odorous. If you are easily offended by fermentation smells, you may not want to continue with this recipe. Or choose a spot in your home where the smell while fermenting won’t offend you or others. We just love the overall health benefits of Natto and we are completely accustomed to the funky smells that can come with fermenting foods. 

As always, when dealing with naturally fermenting foods, please sterilize all tools prior to starting this process. You want to make sure there isn’t any cross-contamination of bacteria to ensure your fermented food is safe for eating. Boil some clean water, and pour over all tools (mixing/soaking bowl, spoons, stainless steel strainer basket, etc.) you will be using to ensure they’re sterilized. Or you can also double ensure they’re sterilized by boiling any tools in boiling water for about 5 minutes. 

 

Benefits of eating Natto

Natto (fermented soybeans) makes your skin glow. Eat Natto regularly for about a month and you will notice your skin having more of a glow to it. You only need to eat about two tablespoons per day for great health benefits.

1. Probiotic-rich food (1) – optimizes digestive health and can help treat diarrhea, ulcerative colitis, and IBS (2).
2. Rich in Vitamin K (3) – which helps with heart health (4), reduces the risk of arterial calcification and supports bone health (5).
3. Contains Nattokinase (6)

 

Ingredients needed to make your own homemade Natto

You only need TWO ingredients to make our homemade natto recipe:

• Dry soybeans (preferably organic)
• Water

 

Tools needed to make this Natto recipe

• Fermented soybean maker machine – We couldn’t find a recent Cuckoo model that specifically stated it could also ferment beans/soybeans. We found a different brand that states it can make Natto.
• Stainless steel strainer basket – Make sure to choose the quart size that fits in your machine.
• Stainless bowl (to soak soybeans)

We used a Cuckoo brand fermented soybean maker machine to make this recipe – see the picture of the one we used below. Results may vary if you don’t have the exact same make/model we are using. That’s part of the fun of cooking is to experiment and also make our baseline recipe of instructions work for you and your own tools.

If you don’t have a fermented soybean maker, you could try using an Instant Pot using the same instructions with a minor adjustment to the last step. For the final step when using our Cuckoo fermented soybean maker we used the “keep warm” function for 48 hours, if you’re trying the Instant Pot (IP) then use the “Yogurt” button instead for 48 hours. Place the stainless strainer basket of pressure-cooked soybeans right inside the IP. You want there to be gooey, strands forming when you stir the soybeans. This is when you know the Natto is finished. We are not using Natto starter in our recipe, so this is why it takes much longer (48 hours) so that it has time to ferment and create beneficial cultures/bacteria. Note: We have not personally tested using the Instant Pot or pressure cookers with a yogurt function, but we hope to test it in the near future ourselves. We will update this recipe post whenever we do test an Instant Pot or other electric pressure cookers ourselves to confirm the results. 

How to make our homemade Natto

Step 1: Sanitize your tools

Boil some clean water, and pour over all tools (mixing/soaking bowl, spoons, stainless steel strainer basket, etc.) you will be using to ensure they’re sterilized. Or you can also double ensure they’re sterilized by boiling any tools in boiling water for about 5 minutes. 

 

Step 2: Prep the soybeans

Rinse the soybeans in clean water twice to ensure you remove any dirt or debris. 

 

Step 3: Soak the soybeans in clean water

Soak the dry soybeans in clean water for 24 hours. Within those 24 hours, change the water out three times (about 10-hour intervals). Replace each time with fresh, clean water and continue soaking. We do not remove the soybean skins at any point throughout the process. 

Step 4: Pressure cook the soaked soybeans

Now, we’re going to pressure cook the soybeans. You can use the same water it is soaking in. Place the soaked soybeans and water into the pressure cooker. Remove or add water until you have about an inch of water over the top of the soybeans. Pressure cook on high pressure for 30 minutes. The soybeans are done with they smush easily between your fingers. We do not remove the soybean skins at any point throughout the process. 

Once the time is up, release the pressure and drain into a colander or drainage basket. Place the soybeans on the counter in the stainless strainer basket for 2 hours to allow them to dry out a bit. 

Step 5: Let it ferment/cook for 48-hours

After the two hours is up, place it in the Natto-making machine. Put it on the “keep warm” function for 48 hours. 

After 48 hours, your Natto is ready. You want there to be gooey, strands forming when you stir the soybeans. This is when you know the Natto is finished.

Serving suggestions and how to eat Natto

We personally love to eat a couple of tablespoons of natto with a drizzle of sesame oil. Simply mix the Natto and sesame oil together and eat it just like that for a healthy dose of this fermented food. Sometimes we’ll eat it on top of rice as well. Traditionally in Japanese culture, natto would be eaten with breakfast on top of freshly steamed rice with a drizzle of soy sauce. You can also use natto in miso soup, or even in Korean-style fermented soybean paste (doenjang) soup – see one of our recipes here! 

Storing your freshly made Natto

Store in the fridge in an airtight container for up to a month. The longer it is stored the more pronounced the flavor will become. You could also freeze individual-sized servings and keep them in your freezer. Once thawed it is recommended to eat within a week. 

 

HUNGRY FOR MORE? Subscribe to our newsletter and follow along on Facebook, Pinterest, Twitter, and Instagram for all of the latest updates.
 

Homemade Fermented Natto

Yield: 16 Servings

Prep Time: 1 day

Cook Time: 2 days 30 minutes

Additional Time: 2 hours

Total Time: 3 days 2 hours 30 minutes

Natto is simply soybeans that are fermented that are a staple in traditional Japanese cuisine. You only need two ingredients for our recipe, dried soybeans, and water.

Print

Ingredients

• 1 lb dry organic soybeans
• Water

Instructions

1. Boil some clean water, and pour over all tools (mixing/soaking bowl, spoons, stainless steel strainer basket, etc.) you will be using to ensure they're sterilized. Or you can also double ensure they're sterilized by boiling any tools in boiling water for about 5 minutes.
2. Rinse the soybeans in clean water twice to ensure you remove any dirt or debris.
3. Soak the dry soybeans in clean water for 24 hours. Within those 24 hours, change the water out three times (about 10-hours intervals). Replace each time with fresh, clean water and continue soaking. Note: We do not remove the soybean skins at any point throughout the process. 
4. Now, we’re going to pressure cook the soybeans. You can use the same water it is soaking in. Place the soaked soybeans and water into the pressure cooker. Remove or add water until you have about an inch of water over the top of the soybeans. Pressure cook on high pressure for 30 minutes. Once the time is up, release the pressure and drain into a colander or drainage basket.
5. Place the soybeans on the counter in the colander/drainage basket for 2 hours to allow them to dry out a bit.
6. After the two hours is up, place it in the Natto-making machine. Put it on the “keep warm” function for 48 hours.
7. After 48 hours, the Natto is ready.

Notes

Results may vary if you don't have the exact same make/model machine we are using. That's part of the fun of cooking is to experiment and also make our baseline recipe of instructions work for you and your own tools. When we have a chance to test this recipe with an Instant Pot using the yogurt function, we will update this recipe post.

---

Disclaimer: Under no circumstances shall this website and the author(s) be responsible for any loss or damages resulting from the reliance of the given nutritional information or ingredient/product recommendations. Recommended ingredients/products can change their formula at any time without this website and author’s awareness. It is your responsibility (the reader’s) to check the label/ingredients of any product prior to purchasing and/or using. We greatly appreciate your support and understanding.