How To Make Natto A Step-by-Step Guide To Fermented Soybeans

Aug 27, 2025 by ADMIN 61 views

Hey guys! Ever heard of natto? It's this super interesting Japanese dish made from fermented soybeans. Yeah, I know, fermented soybeans might not sound like the most appetizing thing in the world, but trust me, it’s worth giving a try! Natto is a staple in Japanese cuisine, and it's packed with nutrients and has a unique flavor profile that's definitely an acquired taste, but once you acquire it, you’ll be hooked! So, if you’re feeling adventurous and want to dive into the world of Japanese dishes, let’s learn how to make natto at home. It's easier than you think, and you'll be enjoying this traditional dish in no time! This comprehensive guide will walk you through each step, ensuring you create the perfect batch of natto right in your own kitchen. From selecting the right soybeans to mastering the fermentation process, we've got you covered. Get ready to embark on a culinary journey and discover the delicious world of homemade natto!

What is Natto?

Before we jump into the recipe, let's talk a little more about what natto actually is. Natto is a traditional Japanese food made from soybeans that have been fermented with Bacillus subtilis var. natto. This fermentation process gives natto its distinctive pungent smell, strong flavor, and sticky, stringy texture. Imagine a dish that's earthy, nutty, and a little bit cheesy all at the same time – that's natto for you! The history of natto dates back centuries, with some accounts suggesting it originated as early as the Nara period (710-794 AD). Legend has it that natto was discovered by accident when cooked soybeans were stored in rice straw, which naturally contains Bacillus subtilis. Over time, the soybeans fermented, and natto was born. Natto has since become a beloved part of Japanese cuisine, enjoyed by people of all ages.

One of the key reasons natto is so popular in Japan is its incredible nutritional profile. It’s a powerhouse of nutrients, packed with protein, fiber, vitamins, and minerals. Natto is an excellent source of vitamin K2, which is crucial for bone health, and it’s also rich in nattokinase, an enzyme known for its potential cardiovascular benefits. Additionally, natto is a fermented food, meaning it contains probiotics that promote gut health. Incorporating natto into your diet can contribute to a healthy digestive system and overall well-being. The fermentation process not only enhances the nutritional value of soybeans but also makes them easier to digest. This is particularly beneficial for individuals who may have difficulty digesting legumes. Natto is a great alternative protein source for vegetarians and vegans, providing essential amino acids that are necessary for muscle growth and repair. Plus, the high fiber content in natto can help you feel full and satisfied, making it a great addition to a balanced diet.

Natto is also incredibly versatile in the kitchen. While it’s traditionally served over rice, often with a raw egg, soy sauce, and Japanese mustard (karashi), there are countless ways to enjoy it. You can add it to miso soup, mix it into salads, or even use it as a topping for toast. Some people enjoy natto with okonomiyaki (savory pancake) or as a filling for sushi rolls. The possibilities are endless! The strong, distinct flavor of natto pairs well with a variety of other ingredients, allowing for creative and delicious culinary experiments. Whether you’re a seasoned natto enthusiast or a curious newcomer, there’s always a new way to enjoy this traditional Japanese delicacy. Don't be afraid to try different combinations and find your favorite way to eat natto. You might be surprised at how much you like it!

Why Make Natto at Home?

You might be wondering, “Why should I make natto at home when I can just buy it at the store?” That’s a fair question! While store-bought natto is convenient, making your own natto gives you a few key advantages. First and foremost, making natto at home allows you to control the ingredients and ensure the highest quality. You can choose organic, non-GMO soybeans and avoid any unnecessary additives or preservatives. When you make natto from scratch, you know exactly what’s going into your food. This is particularly important for those who are health-conscious or have dietary restrictions. By selecting the best ingredients, you can create a natto that is both nutritious and delicious.

Secondly, homemade natto often tastes better than store-bought versions. Freshly made natto has a richer, more nuanced flavor and a superior texture. The fermentation process can vary depending on the conditions, and making natto at home allows you to fine-tune the process to your liking. You can experiment with different fermentation times and temperatures to achieve the perfect taste and consistency. Many natto enthusiasts find that the flavor of homemade natto is far superior to what you can find in stores. The freshness and quality of the ingredients truly shine through in the final product. Plus, the satisfaction of creating something delicious from scratch is an added bonus!

Finally, making natto at home can be a fun and rewarding culinary project. It's a great way to connect with the traditions of Japanese cuisine and learn a new skill. The process of fermentation is fascinating, and watching your soybeans transform into natto is a truly satisfying experience. Making natto is also a great way to impress your friends and family with your culinary skills. You can share your homemade natto with others and introduce them to this unique and healthy food. It’s a conversation starter and a delicious treat all in one! So, if you’re looking for a new culinary adventure, making natto at home is definitely worth a try. You’ll not only enjoy the delicious results but also learn a lot about fermentation and Japanese cuisine along the way.

Ingredients and Equipment

Alright, let's get down to the nitty-gritty. To make natto at home, you'll need a few key ingredients and some basic equipment. Don't worry, you probably already have most of the equipment in your kitchen! Here’s a comprehensive list to get you started:

Ingredients:

Soybeans: This is the star of the show! You'll need about 1 cup of dry soybeans. I recommend using small to medium-sized soybeans, as they tend to ferment better. You can find them at most Asian grocery stores or online. Opt for organic, non-GMO soybeans if possible, to ensure the highest quality and best flavor. Different varieties of soybeans can yield slightly different results in terms of taste and texture, so feel free to experiment with different types to find your preference. The quality of your soybeans will significantly impact the final product, so choosing the right ones is crucial.
Natto Starter: This contains the Bacillus subtilis var. natto bacteria, which is essential for fermentation. You can find natto starter in a few forms: freeze-dried spores, liquid starter, or even a small amount of store-bought natto. If you’re using freeze-dried spores, you’ll need to rehydrate them before use. Liquid starters are ready to use right away, and using a bit of store-bought natto is a great way to kickstart your first batch. The natto starter is what transforms the cooked soybeans into the sticky, flavorful natto we know and love. Make sure to use a high-quality starter for the best results. Using a reliable starter ensures that the fermentation process will be successful and that your natto will have the characteristic flavor and texture.
Water: You'll need water for soaking and steaming the soybeans. Filtered water is always a good choice to avoid any unwanted flavors or contaminants. The water you use should be clean and pure to ensure the best results in your natto-making process. The quality of the water can affect the flavor and texture of the final product, so using filtered water is a simple way to ensure a better outcome.

Equipment:

Large Bowl: For soaking the soybeans. Make sure it’s large enough to hold the beans and plenty of water, as the soybeans will expand significantly during soaking. A large bowl will provide ample space for the soybeans to hydrate properly, which is essential for the fermentation process. Using a bowl that is too small can result in uneven soaking and affect the final quality of your natto.
Steamer or Pressure Cooker: For cooking the soybeans. Steaming is the traditional method, but a pressure cooker can significantly reduce cooking time. If you’re using a steamer, make sure it’s large enough to hold all the soybeans in a single layer. A pressure cooker can cook the soybeans more quickly and efficiently, which is a great option if you’re short on time. The goal is to cook the soybeans until they are tender but not mushy, so choose the method that works best for you.
Sterilized Container: This could be a shallow tray, a container with holes, or even a yogurt maker. The container should be clean and sterilized to prevent the growth of unwanted bacteria. You can sterilize the container by boiling it for a few minutes or using a sterilizing solution. The type of container you use can affect the fermentation process, so choose one that allows for good airflow and temperature control. A shallow tray or container with holes is ideal for promoting even fermentation and preventing the natto from becoming too moist.
Incubator: An incubator helps maintain the optimal temperature for fermentation. You can use a yogurt maker, a dedicated fermentation chamber, or even a warm spot in your oven with the light on. Maintaining a consistent temperature is crucial for successful natto fermentation. The ideal temperature range is between 100-110°F (38-43°C). Using an incubator ensures that the natto ferments properly and develops the characteristic flavor and texture.
Thermometer: To monitor the temperature during fermentation. A reliable thermometer is essential for ensuring that the fermentation process is happening at the right temperature. You can use a digital thermometer or a traditional kitchen thermometer. Monitoring the temperature allows you to make adjustments as needed to maintain the optimal conditions for fermentation. Keeping the temperature within the ideal range will help ensure that your natto turns out perfectly.
Plastic Wrap or Lid: To cover the container during fermentation. This helps maintain humidity and prevent contamination. If you’re using plastic wrap, make sure to poke a few holes in it to allow for some airflow. A lid can also be used, but it should not be airtight, as the natto needs some oxygen to ferment properly. Covering the container helps to create a stable environment for the natto to ferment and prevents the growth of unwanted bacteria.

With these ingredients and equipment in hand, you’re well on your way to making delicious homemade natto! Let's move on to the step-by-step instructions.

Step-by-Step Instructions

Okay, guys, let’s get to the fun part – actually making the natto! Here’s a step-by-step guide to help you through the process:

Step 1: Soak the Soybeans

First, you'll want to thoroughly rinse 1 cup of dry soybeans. This helps remove any dirt or debris. Then, place the soybeans in a large bowl and add enough water to cover them completely. Soybeans are like little sponges, and they'll soak up a lot of water, so make sure you add plenty! Let the soybeans soak for at least 12 hours, or even better, overnight. During this time, they’ll expand to about double their original size. Soaking the soybeans is a crucial step because it softens them and makes them easier to cook. Properly soaked soybeans will cook more evenly and result in a better texture in the final natto. If the soybeans aren't soaked long enough, they may not cook through properly, which can affect the fermentation process. So, be patient and give them the time they need to soak up all that water!

Step 2: Cook the Soybeans

Once your soybeans are nicely soaked, it’s time to cook them! You have a couple of options here: steaming or pressure cooking. Steaming is the traditional method, and it’s a great way to ensure the soybeans cook evenly. To steam, drain the soaked soybeans and place them in a steamer basket over a pot of boiling water. Cover and steam for about 2-3 hours, or until the soybeans are very tender. They should be easily mashed with your fingers. If you’re short on time, a pressure cooker is your best friend. Simply place the drained soybeans in the pressure cooker with about 2 cups of fresh water. Cook on high pressure for 15-20 minutes, then let the pressure release naturally. This method significantly reduces cooking time while still achieving perfectly cooked soybeans. Whether you choose to steam or pressure cook, make sure the soybeans are cooked until they are very tender. Undercooked soybeans won't ferment properly, and the natto will not have the desired texture and flavor. Properly cooked soybeans are essential for a successful batch of natto.

Step 3: Prepare the Natto Starter

While the soybeans are cooking, let's get the natto starter ready. If you're using freeze-dried spores, you'll need to rehydrate them. In a small, sterilized bowl, mix the spores with about 2 tablespoons of cooled, boiled water. Stir gently to dissolve the spores and let it sit for about 15-20 minutes. This rehydrates the bacteria and gets them ready to work their magic on the soybeans. If you're using a liquid starter or store-bought natto, you can skip this step. Just make sure you have your starter ready to go when the soybeans are cooked. The natto starter is what contains the Bacillus subtilis bacteria that are responsible for the fermentation process. Using a properly prepared starter ensures that the fermentation will occur as expected and that your natto will have the characteristic flavor and texture. Rehydrating the spores correctly is crucial for activating the bacteria and setting the stage for successful fermentation.

Step 4: Mix Soybeans with Natto Starter

Once the soybeans are cooked, drain them immediately and transfer them to a sterilized container. It's important to work quickly here, as you want to add the natto starter while the soybeans are still hot (around 130-140°F or 55-60°C). This temperature range is ideal for the Bacillus subtilis bacteria to thrive. Pour the rehydrated natto starter (or liquid starter/store-bought natto) over the hot soybeans and mix thoroughly. Make sure the starter is evenly distributed throughout the soybeans. This ensures that the fermentation process will occur uniformly. Mixing the soybeans with the starter while they are still hot helps the bacteria to activate and start the fermentation process. If the soybeans cool down too much, the bacteria may not be as effective, which can affect the final result. So, act quickly and mix thoroughly to get the best results.

Step 5: Ferment the Natto

Now comes the waiting game! Cover the container with plastic wrap, making sure to poke a few holes for airflow. The bacteria need oxygen to ferment properly. You can also use a lid, but don’t seal it tightly. Place the container in your incubator. The ideal fermentation temperature is between 100-110°F (38-43°C). If you’re using a yogurt maker, this should be easy to maintain. If you don’t have a dedicated incubator, you can use a warm spot in your oven with the light on, but be sure to monitor the temperature closely. Let the natto ferment for 18-24 hours. The fermentation time can vary depending on the temperature and the strength of your starter. During this time, the bacteria will work their magic, transforming the soybeans into natto. Maintaining a consistent temperature is crucial for successful fermentation. Fluctuations in temperature can affect the activity of the bacteria and the quality of the final product. Be patient and allow the natto to ferment for the full duration to develop its characteristic flavor and texture.

Step 6: Refrigerate the Natto

After the fermentation period, your natto should have a strong, pungent smell and a sticky, stringy texture. If it looks and smells right, it's time to refrigerate it. Remove the container from the incubator and place it in the refrigerator for at least 24 hours. This chilling period is important because it stops the fermentation process and allows the flavors to develop fully. Refrigerating the natto also helps to firm up its texture and make it easier to handle. The chilling period allows the flavors to meld together and create the unique taste of natto. It also helps to reduce the intensity of the smell, making it more palatable for some people. So, don't skip this step! Refrigerating the natto is essential for achieving the best flavor and texture.

Serving and Enjoying Natto

Congratulations! You’ve made your own natto. Now, let’s talk about how to enjoy it. Natto is traditionally served over rice, often with a few condiments. Here are some popular ways to serve and enjoy natto:

Traditional Serving Suggestions:

Over Rice: This is the classic way to eat natto. Place a serving of natto over a bowl of hot, freshly cooked rice. The warmth of the rice helps to enhance the flavor of the natto. Mix the natto and rice together for a delicious and satisfying meal. Adding natto to rice is a simple and nutritious way to enjoy this fermented soybean dish. The combination of flavors and textures is a culinary experience that many people find addictive.
With Soy Sauce: A drizzle of soy sauce is a must for many natto lovers. The saltiness of the soy sauce complements the earthy flavor of the natto perfectly. You can adjust the amount of soy sauce to your liking. Some people prefer a light drizzle, while others like to drench their natto in soy sauce. Experiment to find your perfect balance. Soy sauce is a classic condiment for natto, and it adds a savory element that enhances the overall flavor profile. The umami in soy sauce pairs well with the fermented flavors of natto, creating a delicious combination.
With Japanese Mustard (Karashi): A touch of karashi, Japanese mustard, adds a spicy kick to the natto. Karashi is similar to Dijon mustard but with a bit more heat. A small dab is usually enough to add a noticeable zing. If you’re a fan of spicy foods, you’ll love the addition of karashi to your natto. The spiciness of the mustard balances the richness of the natto and creates a dynamic flavor experience. Karashi is a traditional accompaniment to natto in Japan, and it’s a great way to add some excitement to your meal.
With a Raw Egg: Many people enjoy mixing a raw egg into their natto. The egg adds a creamy texture and richness to the dish. Simply crack an egg over the natto and rice and mix it all together. The raw egg coats the natto and rice, creating a silky and flavorful combination. Using high-quality, fresh eggs is important for this serving suggestion. The egg adds a protein boost to the meal and enhances the overall nutritional value of the dish. Some people find that the raw egg mellows out the strong flavor of the natto, making it more palatable.
With Green Onions: Chopped green onions add a fresh, mild onion flavor and a bit of crunch to natto. Sprinkle some green onions over your natto and rice for added texture and flavor. The green onions provide a bright and refreshing contrast to the rich, fermented flavors of the natto. They also add a visual appeal to the dish. Green onions are a simple but effective addition to natto, and they are a popular topping in Japan.

Other Creative Ways to Enjoy Natto:

In Miso Soup: Add a spoonful of natto to your miso soup for an extra boost of flavor and nutrition. The natto will add a unique texture and a savory depth to the soup. The combination of miso and natto is a classic in Japanese cuisine, and it’s a great way to incorporate more fermented foods into your diet. The natto will dissolve slightly into the soup, adding a subtle richness and umami flavor.
In Salads: Mix natto into your salads for a protein-packed and flavorful addition. The natto adds a unique texture and a boost of nutrients to your salad. The strong flavor of the natto pairs well with a variety of salad ingredients, such as leafy greens, vegetables, and dressings. Experiment with different combinations to find your favorite natto salad. Adding natto to salads is a creative way to enjoy this fermented food, and it’s a great way to add some variety to your meals.
On Toast: Spread natto on toast for a quick and easy breakfast or snack. Top it with soy sauce, avocado, or other toppings for added flavor. Natto on toast is a simple but satisfying way to enjoy this fermented soybean dish. The toast provides a crunchy base for the natto, and the added toppings enhance the flavor and texture. This is a great option for those who are looking for a quick and nutritious meal or snack.

Tips and Tricks for Perfect Natto

Making natto can be a bit of an adventure, but with these tips and tricks, you’ll be a natto pro in no time:

Sterilization is Key: Make sure all your equipment is thoroughly sterilized to prevent the growth of unwanted bacteria. This is crucial for successful fermentation. Use a sterilizing solution or boil your equipment for a few minutes to ensure that it is clean. Sterilization is a non-negotiable step in natto making, as it helps to prevent contamination and ensures that the Bacillus subtilis bacteria can thrive. Unwanted bacteria can spoil your natto and make it unsafe to eat, so always take the time to sterilize your equipment properly.
Temperature Control is Crucial: Maintaining a consistent temperature during fermentation is essential. Use a reliable incubator or monitor the temperature closely if using an alternative method. The ideal temperature range for natto fermentation is 100-110°F (38-43°C). Fluctuations in temperature can affect the activity of the bacteria and the quality of the final product. If the temperature is too low, the fermentation process may be slow or incomplete. If the temperature is too high, the bacteria may be killed. Monitoring the temperature closely and making adjustments as needed will help you to achieve the best results.
Use Fresh, High-Quality Soybeans: The quality of your soybeans will directly impact the flavor and texture of your natto. Opt for organic, non-GMO soybeans for the best results. Fresh soybeans will produce natto with a richer, more nuanced flavor. Older soybeans may not ferment as well and can result in a less desirable texture. Choosing high-quality soybeans is an investment in the final product, and it will make a noticeable difference in the taste and texture of your homemade natto.
Don't Be Afraid to Experiment: Natto making is a bit of an art, so don't be afraid to experiment with different fermentation times and temperatures to find what works best for you. Each batch of natto may turn out slightly differently, and that’s part of the fun. Experimenting with different variables can help you to fine-tune the process and create natto that is perfectly suited to your taste. You can try different types of soybeans, adjust the fermentation time, or use different starters. Keep track of your experiments and note what works and what doesn't. With practice, you’ll develop your own natto-making style.
Smell and Texture Are Your Guides: Trust your senses! If the natto smells pungent and has a sticky, stringy texture after fermentation, you're on the right track. These are the key indicators that the fermentation process has been successful. The characteristic smell of natto is strong and earthy, and the texture is sticky and stringy due to the formation of the enzyme nattokinase. If your natto doesn't have these characteristics, it may not have fermented properly. In that case, it’s best to discard the batch and start again. Learning to recognize the signs of successful natto fermentation will help you to consistently produce high-quality natto.

Conclusion

So, there you have it! Making natto at home is a fun and rewarding culinary project. Yes, it takes a bit of time and patience, but the result is a delicious, nutritious, and uniquely flavored dish that you can be proud of. Plus, you get to impress your friends and family with your newfound natto-making skills. Don't be intimidated by the strong smell or sticky texture – give it a try, and you might just become a natto convert! From soaking the soybeans to fermenting them to perfection, each step is a rewarding journey that culminates in a delicious and nutritious dish. Whether you're a seasoned natto enthusiast or a curious beginner, making your own natto at home is a fantastic way to connect with Japanese culinary traditions and enjoy the unique flavors and textures of this fermented soybean dish. So, gather your ingredients, follow these steps, and get ready to embark on your natto-making adventure! You'll be amazed at how easy and rewarding it is to create your own homemade natto. And who knows, you might just discover your new favorite food!