Learn how to make miso from scratch with just 4 ingredients and a little patience. My recipe with step-by-step instructions will guide you from start to finish. When it‘s ready, use your amazing homemade fermented soybean paste to make delicious Japanese dishes!
As a home cook and a Japanese cuisine advocator, I want to be able to share not just the recipes, but also to uphold the tradition of making food from scratch. I believe there is a beauty in preserving the heritage integral to our food culture. Do you agree? This year I’ve taken up a few cooking projects that I’d like to accomplish, and making miso paste from scratch is one of them.
This is my first time making miso, and I can’t be any more excited to share the experience with you!
What is Miso?
Miso (味噌) is a Japanese seasoning produced by fermenting soybeans with salt and koji. It has been used in Japanese cuisine since 1200 AD (a precursor of miso arrived in Japan from China around 600 AD).
As one of Japan’s superfoods, miso is well recognized for its many great health benefits. It is rich in essential minerals and a good source of various B vitamins, vitamins E, K, and folic acid. As a fermented food, miso is full of probiotic that provides the gut with beneficial bacteria that help us to stay healthy.
You might have seen various types of miso available at the grocery stores, but in general, miso can be categorized by 3 factors: ingredients, color, and taste. In Japan, miso can also be categorized by regions.
* To learn more about miso and its different types, please read this detailed miso post on my blog.
My Miso-Making Journey
When I get home from a long trip, I often crave simple homemade miso soup (and onigiri is a plus!). Even though miso is entirely indispensable in my diet and cooking, I realized that I had never made it from scratch before. Like making your own mochi or plum wine, it struck me that there was something special about making your own miso, and I really wanted to do just that!
So if you’re with me, wishing to make this Japanese condiment from scratch, try making your own miso! This miso recipe is based on this Japanese miso company’s tutorial which I found upon my research. I’ll be trying different recipes in the future, and I will update/modify this recipe based on my own experiment.
Easier Than You Think…
Before we start, I wanted to reassure you that making your homemade miso is easier than you think. You will only need a few simple ingredients and a little patience.
Quick Overview of Miso Making
The process of making miso takes 2 days, but it is not until 6 months later only you get to use the product. Umm… are you still here?
It may sound daunting, but the method is actually simple and the result is totally worth the effort!
In my recipe below, I included both Instant Pot and Stove Top options for cooking the soybeans.
Day 1
- Wash soybeans
- Soak soybeans for 18 hours (don’t cut it short!)
Day 2
- Cook soybeans (pressure cook – 20 mins; simmer – 3 to 4 hrs)
- Mash soybeans
- Combine soybeans, salt, and koji
- Pack the mixture into a jar
- Store the miso and wait for 6 months…
What You Need for Making Miso – Ingredients & Tools
4 Simple Ingredients
- Organic soybeans. I purchased organic American soybeans from Whole Foods where you can get the exact amount of soybeans you need from a dispenser. You can also look up Laura Soybeans or purchase them on Amazon.
- Fine sea salt. I used fine sea salt for my miso because it yields the best flavor and is rich in minerals.
- Rice koji. Rice koji is steamed rice (and sometimes with other grains such as barley) that has been treated with a fermentation culture, Aspergillus oryzae, koji-kin (麹菌). The enzymes found in the koji work to break down carbohydrates and proteins into amino acids, fatty acids, and other nutrients during the fermentation process. Here in the US, you can find Cold Mountain brand of rice koji for sale. You can also buy rice koji from Anything from Japan which ships internationally.
- Filtered water. Quality of water plays an important role in making good miso paste, so be sure to use filtered water that is safe and has removed most of the impurities.
The Tools You’ll Need
- Kitchen scale. I recommend getting a kitchen scale (I’ve been using this kitchen scale which I got from Amazon years ago) and measure correctly when you make miso. I usually use the gram measurement for my baking and other traditional Japanese recipes like Tsukemono.
- One-gallon container. You can use any container but I highly recommend the glass one so you can see the miso making progress from the side. I bought a 1-Gallon Biscotti Jar (large) from William Sonoma but you can get an Anchor Hocking Glass Storage Jar from Amazon. Other choices include a stoneware crock or a large plastic bucket.
- Heavy object. Use any heavy object that would fit in your 1-gallon container. A plastic bag of table salt works well. The weight should be 1/3 of the miso weight. In this recipe, the miso weighs 3 kg (6.6 lb) so it should be 1 kg (2.2 lb) salt.
- Large bowl. You will need a large mixing bowl (or a large serving bowl) to combine mashed soybeans and the mixture of koji and salt.
- Plastic wrap. Tightly covered miso with plastic wrap will prevent mold growth.
- Shochu (vodka) and clean towel. We use alcohol to disinfect the container, which will prevent mold growth.
5 Important Cooking Tips
1. Soak soybeans for 18 hours
Dried soybeans take time to absorb moisture (See above photo: 18-hour soaked bean on left vs dried bean on right). To make sure the soybeans are cooked through to the core, you need to soak the soybeans for 18 hours. If you want to start cooking (pressure cook/simmer) soybeans from 10 am, you need to start soaking the soybeans at 4 pm on the previous day.
2. Doneness check by crushing soybeans with fingers
Pressure cook or simmer soybeans until they are soft enough to easily crush between your thumb and pinky.
3. Smash soybeans well
Mash a small amount of hot soybeans at a time to make sure they are pounded to an even consistency. It’s okay to have a small number of chunky soybeans here and there, but you should try your best to mash most of them nicely.
Alternatively, you can use your food processor if you have one, which will definitely speed up the process.
4. Knead the mixture well
Mashed soybeans must be warm or at room temperature when you combine with koji and salt mixture. Knead well to distribute the koji to facilitate good fermentation throughout.
5. Remove air pockets completely
Pack the soybeans in a jar by pressing down each ball of the mixture as firmly as possible to remove any air pockets. This will prevent unwanted mold growth.
The Best time to Make Miso
You can make miso year-round, but for the best result, I recommend making miso in late fall to winter as miso fermentation works great from a cold winter, to a cool spring, and hot summer. Other reasons why fall and winter months are best for making miso at home:
- The air is less humid and less prone to contamination.
- Miso ferments slower in the lower temperatures which helps to develop a deeper flavor.
- Rice and soybeans are harvested in late fall, so you get to use freshly harvested ingredients to make your miso.
The timing/season matters for the speed of fermentation and maturation. For example, miso prepared in summer will be ready in 3-4 months. On the other hand, if it’s prepared in winter, it takes more time to ferment and mature, roughly 6 months.
Keep checking the progress and taste your miso. If the miso reaches the flavor profile you like, store it in the refrigerator as it slows down the speed of maturation, discoloration, and flavor changes.
FAQs
1. Can I halve the recipe?
Yes, you can.
2. What type of miso are we making here?
Since we’re using rice koji, the type of miso in this recipe is considered Kome Miso (米味噌). However, the process and length of fermentation will determine the final color and taste of the miso.
White miso requires a shorter fermentation time (6 months) and you’ll get a sweeter flavor and smoother texture. To make saltier miso, you can leave the miso to ferment for up to 1-1.5 years as the color darkens and the flavor develops stronger.
Having said that, there is a lot more to it than simply categorizing them by type. The method of preparing the soybeans and the ratio of ingredients also play a part in the end product. That is why there are SO MANY types of miso in Japan.
3. Where can I buy rice koji?
In the US, you can find Cold Mountain brand of rice koji for sale. If you live outside of the US, you can buy rice koji from Anything from Japan which ships internationally.
If you live in Oakland, a reader shared that you can buy fresh koji from this shop called Preserved Goods.
4. Can I use a mix of soybeans with other beans like garbanzo (chickpea)?
Yes! If you’re willing to experiment, feel free to mix the soybeans with other types of beans or grains. We have readers who have tried it with garbanzo and northern beans with success. However, the soaking time for garbanzo should take just about 10-12 hours.
5, What should I do if I spot some mold growth during the fermentation?
Mold can be quite normal, especially if you live in a humid climate. Gently scrape them off and transfer the miso into a different container. Make sure to keep an eye on them.
How to Enjoy Homemade Miso
The first thing you should make with your homemade miso is of course some delicious homemade miso soup. But miso has so many more uses you can think of! It’s essentially the most versatile seasoning you can have in your pantry. Think marinades, sauces, glaze, compound butter to baked goods!
Here are just some of my popular miso recipes you can dream of using when you have the jar of miso ready to be enjoyed:
- 15 Delicious Miso Recipes
- Homemade Miso Soup
- Miso Cod
- Miso Ginger Pork
- Miso Chicken
- Miso Salmon
- All-Purpose Miso Sauce
- Miso Ramen
- Miso Butter Cookies
Share Your Miso-Making Journey With Us
I wish you plenty of success in making your own miso! If you have gone ahead and tried my recipe below, please share your experience with us in the comment below. How long did you leave it for? Did you make any adjustments to the ratio? I’d love to hear from you.
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Homemade Miso
Ingredients
- 1.4 lb soybeans (dry; 1 cup of dry soybeans is 6.3 oz/180 g)
- 5 cups rice koji (2 Cold Mountain packages; you can buy it from Anything from Japan, Amazon, or a Japanese grocery store; you can find Cold Mountain and other brands at Nijiya)
- 13.2 oz arajio natural sea salt (for mixing with the rice koji; plus ½ Tbsp more for sprinkling on top of the miso)
- filtered water (for soaking and cooking the soybeans)
Instructions
Before You Start…
- Please note that once you start the fermentation process, it takes about 9 months of mostly inactive time to make miso.
To Start Your Miso (in January/February)
- Gather all the ingredients. For the equipment, you will need 2 large bowls (one should be a very big one), 1 strainer, an Instant Pot (or pressure cooker or a large pot), a clean cloth, alcohol (shochu or vodka), a potato masher (or a food processor), a 1-gallon glass jar to put the miso in, and a bag of 1 kg (2.2 lb) table salt.
- Soak the Dry Soybeans: Gently wash 1.4 lb soybeans thoroughly several times under running water. Note: The foam shown in these images is not soap.
- To a large bowl, add the rinsed soybeans and enough filtered water to reach about 5 inches (10 cm) above the beans. Soak the soybeans for 18 hours.
- Drain the beans. Look how large the beans are now. The right image shows the soybeans before soaking, and the left two soybeans are after 18 hours of soaking. After soaking, the soybeans weigh 1435 g.
- Cook in a Pressure Cooker/Instant Pot: Add the soybeans to the inner pot of an Instant Pot. Add filtered water to about ½ inch (1.2 cm) above the beans (to roughly the 8-cup line for one batch).
- Close the lid and set to High pressure for 20 minutes. Make sure the steam release handle points at Sealing and not Venting.
- Cook on the Stovetop: Alternatively, you can cook the beans on the stovetop. Bring to a boil over high heat, skim off the surface scum, lower to a simmer, and cook for about 3–4 hours, uncovered, until the beans are soft. Add water as needed during simmering. You want to keep the soybeans submerged in just enough water.
- Prepare the Koji Mixture: Meanwhile, in a very large bowl (that‘s big enough to add the mashed soybeans later), combine 5 cups rice koji and 13.2 oz arajio natural sea salt with your hands.
- Clean the Jar: Put some alcohol (shochu, vodka, soju, sake, etc.) on a clean cloth and wipe the inside the jar or container you will store the miso in. This helps to deter mold growth.
- Once the pressure cooking is finished, release the pressure naturally. It will take about 30 minutes until it releases completely and you can open the lid.
- Test the Beans: To check if the beans are cooked enough, press one between your pinky finger and thumb. If it mashes easily and nicely, it’s ready. Drain the soybeans over a bowl to capture the liquid. Save about 1 cup of cooking liquid (just in case; you will only use a small amount of it). NOTE: When you are mashing the beans, you may need a bit of cooking liquid. Ideally, it’s best not to add any cooking liquid at all for this recipe, which is designed to make miso without adding liquid. Water in the miso has a higher risk of potentially causing mold growth.
- Mash the Soybeans: While they‘re still hot, transfer some of the soybeans back to inner pot of the Instant Pot and mash them with a potato masher (or a pestle or bottle). Do this process in batches so it’s easier to mash nicely.
- If you have a food processor, process some soybeans until they are in paste form. Do this in batches so it’s easier to process.
- ONLY if the soybeans look really dry, add a small amount of cooking liquid. As I mentioned earlier, it’s best not to add liquid for this recipe, but I used a little bit. Scoop out the paste and continue with the next batch.
- Mashed soybeans must be warm or at room temperature (NEVER hot) before combining with the koji because heat can kill the koji mold. Mashing takes time (unless you make a small batch), so the soybeans should be cool enough by the time you‘re done mashing all of it.
- Combine the Soybeans and Koji Mixture: Add the warm (not hot!) mashed soybeans into the bowl with the koji and salt mixture.
- Knead well to evenly distribute the rice koji and salt into the soybeans. Take time to do this and mix it well. Add a small amount of the reserved cooking liquid only if necessary.
- Pack the Jar: Using your hands, form tennis ball-sized balls with the mashed soybean mixture.
- Put the balls into the container, one layer at a time. As you add each ball, mash it with your fist and knuckles to ensure that you‘ve eliminated all the air pockets. Press down tightly. If you have a glass jar, you can check for air pockets by looking from the side.
- Repeat the layers until all the balls are pressed tightly in the jar. Pat down and smooth out the surface with a flat palm or your knuckles. Make sure you have space left for placing a weight on top of the miso. If your jar/container is too small, use another container. Clean the inside surface walls of the container with a shochu-soaked cloth/paper towel to deter mold.
- Sprinkle ½ Tbsp arashio natural sea salt on top of the surface.
- Place a sheet of plastic wrap on the surface and make sure to cover it well. I use my adjustable drop lid (otoshibuta) to hold down the plastic wrap while I work on covering the edges and remove it when I was done.
- Put heavy objects (or rocks) on top of the entire surface of the miso. I put 1 kg (2.2 lb) of inexpensive table salt in a plastic bag and placed it on top.
To Begin Fermentation
- Cover the jar with the lid; DO NOT use an airtight lid. Write today‘s date on some masking tape and label the jar. Place the miso in a dark and cool place for at least 3 months. I put it in a storage closet underneath my stairs. You can also use a dark pillowcase and try to find a darker spot in the house.
To Stir After 3 Months (in April/May)
- Check the miso quickly to avoid exposure to air. If you see any mold on the surface, carefully scrape it off. Stir the miso from the bottom up to avoid mold forming. Clean the inside surface walls of the container with a shochu-soaked cloth to deter mold. Smooth the surface, place a new plastic wrap on top, and put the weight back on top. Place the container back in a dark and cool place for another 3 months.
To Stir After 3 More Months (in July/August)
- During the summer months, the fermentation is faster but the chance of mold growth is higher. Stir the miso from the bottom up every 2–3 weeks and check your jar regularly and remove any mold appearing on the surface. Even if a layer of mold covers the entire surface, the miso below should be fine. Just scrape off the surface to a sufficient depth to where you only see mold-free miso. Clean the inside walls of the container with a shochu-soaked cloth to deter mold. Smooth the surface, place a new plastic wrap on top, and put the weight back on top. Place the container back in a dark and cool place.
When the Miso is Done (in September)…
- Because San Francisco has a cool climate year-round and does not get hot, I waited for about a year to mature my miso (darker and saltier miso). Remove the weights once the miso is done.
To Store
- Divide the miso into smaller containers so they will fit in your refrigerator. Store it in the refrigerator to prevent overfermenting. Now, you can enjoy your own miso paste made with patience, love, and perseverance.
i just need to say that i LOVE the miso that comes from this recipe!! ive made it 3 years in a row now, and this time… im going to double the recipe because everyone is mobbing my miso!
thank you for the awesome recipe, i feel very lucky to have found it!
Hi, Kelly! Aww.🥰 We’re so glad you enjoyed Nami’s recipe!
Thank you very much for your great review and sharing your experience with us.
Happy cooking!
A bit confused as per the calculator utilized on this site. The salt additions by dry weight of Koji and Soybeans is 22%. That’s extremely high and it was outlined on here that it’s a 12.5% recipe. This seems very off unless you’re going by the weight of the cooked soybeans
Hi Alex! Thank you for reading Nami’s post!
The salt amount is not calculated based on the dry beans. It’s based on the final weight. We hope this helps!
Hi! I’m excited to try this recipe, but I will be out of town for a few months during the “After 3 More Months” phase when you have to stir it every few weeks! Can I leave it in the fridge during this time to pause the fermentation so I don’t need to stir it, and then continue once I’m back?
Hello, Amanda! We’re pleased you’re looking forward to making miso with Nami’s recipe!
You may skip mixing the miso every few weeks and store it in a dark, cool area for an additional three months. If you place the miso in the fridge during the period, fermentation will slow down, and once in the fridge, miso is easily spoiled if brought to room temperature.
We hope this helps!
I made this recipe in February and stored it under the stairs where it is cool and dark all year round. I checked after 3 months and 4 months and I see no difference, am I doing something wrong?
Hi Ken, Thank you for trying Nami’s recipe.
Not to worry.🙂 The process of making miso might take a long time, depending on the weather. As summer approaches, fermentation will pick up speed, so make sure to stir the miso from the bottom up every 2-3 weeks and see how it goes.
We hope this helps!
Is there a low salt way to make this? (If so, how do I know how little I can add while also being sure the miso is safe to consume?) When soaking the soybeans, are they soaking at room temperature? If so, how do they remain safe when food safety time is usually 2 hours? (This question is a genuine question not intended to sound argumentative. I’m genuinely seeking to understand).
I’m not allowed to comment without giving a star rating, and I don’t find that fair. I haven’t tried this recipe, so I’m not qualified to rate it.
Hello, Laura! Thank you for taking the time to read Nami’s post and try her recipe!
Miso may be prepared with a salt content of 5-20%. Nami’s recipe currently uses 12.5%, which is the most straightforward approach to avoiding mold. You may attempt 10% (salt: 292 g) for this recipe, but be aware that the fermenting process will be faster than stated in the recipe.
In terms of soaking time, you can drain the soybeans when they reach the size shown in the photo in Step 4. If you live in an extremely humid environment, we recommend shortening the soaking time and checking the bean size.
We hope this helps!
I don’t know if this helps but I live in a warm climate so whenever I soak anything I leave it in the fridge, just in case. It doesn’t seem to affect soaking time etc and it’s just a way to make sure things are safe. For nice soft soybeans, I soak them 20-24 hours in the fridge before cooking. The only problem for me is to find the space in my fridge… 😉
Thank you for this recipe! My jar of miso has been fermenting for almost two months now, and I checked the jar but it looks the same as when I first began the process… Is this normal? Around when should I expect to see the soybeans breakdown or change color? I’m worried that nothing is happening in there and I wasted the last few months of cold weather 🙁
Hello, Shannon. Thank you for attempting Nami’s recipe!
The processing time will vary depending on the weather. As a result, we encourage you to wait a bit longer.
Please read the “To Store” section of the recipe card carefully, and don’t forget to stir the miso!😉
We hope this helps!
Thank you for this helpful and informative website. I plan on making a batch of miso as soon as I get my shipment of Koji. I do plan on substituting Himalayan or similar salt for the seasalt. The reason for that (according to what I have learned) is that most if not all recently harvested seasalt contains microplastics.
Hi David! Thank you so much for reading Nami’s post and trying her recipe!
We hope you enjoy making homemade Miso and the flavor. Happy Cooking!
Hi!!! I am so excited to see how my miso will turn out. I am a bit worried though because I forgot that it needed to be stirred every few weeks!! I made it 8/1 and I have t roughly once a month and there is no mold but it is a bit over 6 months now. Should I still go in and stir it?
Thank you!!
Hi Nancy, Thank you so much for trying Nami’s recipe!
If you live in a cooler area and plan to let it form longer, you can stir them, but if you live in a warmer area and Miso is ready, you do not need to stir it now.
We hope this helps!
Hello! Excited to try this recipe, i have a question concerning if I divided the finished soybean paste between smaller glass jars. With the difference in air exposure have a negative effect on the finished miso? Thank you!
Hi Katie! Thank you for trying Nami’s recipe!
We are so happy to hear you are excited to try the homemade Miso recipe!
Yes. Miso can be made in smaller jars.
We hope you enjoy it!
Hi Namiko, I am planning to try out this recipe, but I was wondering whether the same ratios can be used if I have Barley Koji rather than Rice Koji?
Hi Matt! Thank you very much for trying Nami’s recipe!
Yes. You can use Barley Koji instead of Rice Koji for this recipe.
We hope this helps!
Hi Namiko,
What do you consider the minimum koji rice to dry soybeans ratio for making miso? I know most recipes ask for equal weight but would 200g koji rice to 1Lb soybeans work? Thanks
Hi Sari, Thank you very much for reading Nami’s post and trying her recipe!
Usually, equal part of Koji rice or more, and we have never tried making Miso with a lower amount of Koji rice.
We are afraid that the ratio might not work.
We hope this helps!