Small-Batch Homemade Miso Paste Recipe for Beginners

5 from 1 vote

180 14

Serves kg

Vegan

Interested in making traditional Japanese fermented food at home? This beginner-friendly, small-batch miso paste recipe is a great place to start! I’ll walk you through the ingredients and each step of the process, along with helpful tips for successful fermentation.

Want to make a bigger batch? Check out my large-batch miso recipe!

Why You Will Love This Recipe

Makes a manageable 1 kg batch, perfect for beginners.
Uses just three simple ingredients.
Includes a step-by-step video and helpful tips.

Learn more here: What Is Miso? A Simple Beginner’s Guide

Recipe Ingredients

You’ll need the following ingredients to make this Miso Paste Recipe:

Soybeans: Use dried soybeans, preferably larger ones if available. I use Toyomasari, a Japanese variety with a naturally rich flavor, but any good-quality dried soybeans will work.
Dried Rice Koji: Rice koji is an essential ingredient in miso. Its enzymes break down proteins and starches, helping develop the miso’s rich umami and subtle sweetness. It can be difficult to find outside Japan, but it is often available at Japanese grocery stores or online.
Salt: Any regular cooking salt you normally use will work. Choose a fine-grain salt, as very coarse salt may not dissolve or mix evenly throughout the miso.

Equipment

Here are the essential tools you’ll need to make miso paste:

Pressure Cooker: A pressure cooker significantly reduces the time needed to cook the soybeans. If you don’t have one, simmer them in a large pot for about 3–4 hours, adding water as needed, until they are soft enough to crush easily between your fingers.
Food Processor: I use a food processor to mash the soybeans quickly and evenly. You can also use a potato masher or place the cooked soybeans in a sturdy plastic bag and crush them with a rolling pin or your hands.
Fermentation Containers: Use clean, food-grade plastic containers or glass jars. For this recipe, I use a 1-liter plastic container.
Weight: Placing a weight on top limits the miso’s exposure to air, helping reduce the risk of mold and oxidation. For this 1 kg batch, use a weight of about 200–300 g. A water-filled bottle or an unopened bag of salt works well as a substitute.

How To Make Miso Paste: STEP BY STEP

Here’s a quick visual guide! Check the recipe card below for the video and full details!

Day 1: Soak the Soybeans

Step 0

Place the soybeans in a large bowl. Cover with plenty of water and soak overnight.

Day 2: Make the Miso

Step 1

Cook the soybeans in a pressure cooker.

Step 2

Break dried rice koji into pieces and mix it with salt.

Step 3

Mash the soybeans using a food processor until smooth.

Step 4

Combine the mashed soybeans, rice koji, and sea salt.

Step 5

Form the balls and pack them into the container, pressing with your fist.

Step 6

Cover the surface with plastic wrap and place a weight on it.

Cover the surface with a cloth to prevent bugs and dust, and store in a cool place. Let it ferment for six months to a year.

Recipe Tips

Check Your Pressure Cooker: Cooking times vary depending on the type of pressure cooker you use, so be sure to follow the instructions in your manual. The soybeans are ready when you can easily crush them between your fingers.
Remove Air Pockets: Air pockets can encourage unwanted mold during fermentation. Firmly shape the mixture into miso balls, then pack them tightly into the container, pressing down well as you go.
Cover the Surface Tightly: Press plastic wrap directly onto the surface of the miso to limit its exposure to air. This simple step helps reduce the risk of mold while the miso ferments.

Fermenting and Aging Miso Paste

Where To Ferment Miso Paste

Miso fermentation takes place at room temperature, not in the refrigerator. Find a cool, dark place out of direct sunlight for your container. Suitable spots include a storeroom, basement, pantry, entrance area, or under-floor storage. In my case, I like to keep mine in a pantry under the stairs.

Tips for the Aging Period

Homemade miso usually takes 6 to 12 months to be ready, depending on your taste preference and environment.
A longer aging period produces a richer taste, while a shorter period gives a lighter flavor.
Miso is often prepared in winter because the cold temperatures reduce bacteria and mold, allowing fermentation to progress slowly and steadily. It starts fermenting slowly in spring, accelerates in summer, and then slows down again in autumn, deepening the flavors.
For your reference, if you prepare miso in February, it’s best to eat it around October (8 months later). If you prepare it in May, it’s best to eat it around November (6 months later).
If miso over-ferments, the aroma can become too strong, occasionally developing a sour taste or an ammonia-like odor.

One Month Fermentation Check

Once you start fermenting miso, check its progress after one month. You might notice a liquid rising to the surface called “miso tamari.”

Miso tamari is a highly concentrated miso extract that separates during aging. Don’t discard it! This liquid forms a protective layer, preventing the miso from direct air contact and safeguarding it from mold and bacteria.

Six Month Fermentation Check

This is my 6-month miso. It has a pleasant savory aroma, and the taste is rich in umami with just a hint of sweetness. I was aiming for a lighter color, but that’s okay.

Due to the extremely hot summer this year, fermentation progressed quickly, deepening the color even within 6 months.

Signs of Properly Aged Miso: What To Look For

Here are things to look for to know if your miso is aged and ready to eat:

Color: Soybeans start off light brown, but as they age in fermentation, they gradually darken. When they reach a miso-like color, it’s a sign that it’s aging correctly.
Aroma: At the beginning of preparation, there isn’t much smell. However, as it ages, it develops a distinct miso-like aroma, then you’ll know it has been properly aged.
Taste: As miso ages, its taste becomes more profound and complex. Be sure to taste it. Take a piece of miso from about 1cm below the surface, mix it with hot water, and taste. Based on the taste, decide whether to extend or stop the fermentation.

Dealing with Mold During Fermentation

If mold appears, remove the surrounding area with a spoon. If you see a fluffy white ring on the edge of the container, it is also a mold. Be sure to remove all of it and wrap the miso tightly to prevent air contact for further fermentation.

Storage

Once the miso reaches your preferred flavor, transfer it to the refrigerator to slow down further fermentation and darkening. You can also store miso in the freezer. It doesn’t freeze solid; it may become slightly stiff, but you can still easily scoop it out and use it.

How To Use Miso Paste

Homemade miso paste can be used in many different dishes, not just miso soup. Check out my collection of recipes using miso paste.

Your Questions Answered

How long does homemade miso take to ferment?

Homemade miso usually takes about 6 months to 1 year to ferment. The longer it ages, the deeper and richer the flavor becomes.

Where should I keep the container while the miso ferments?

Keep the miso container in a cool, dark place at room temperature, away from direct sunlight and heat. A pantry, cupboard, or storage area works well.

What should I do if mold appears?

If you see a small amount of mold on the surface, don’t panic. Carefully remove the mold and a little of the miso around it with a clean spoon. Then wipe the container, cover the surface tightly again, and continue fermenting.

How do I know when miso is ready?

Miso is ready when it has a rich aroma, deeper color, and a balanced salty, savory flavor. To taste it, take a small amount from about 1 cm below the surface, mix it with hot water, and check the flavor.

I found liquid on top of the miso. What should I do?

The liquid on top is called tamari, and it’s a natural part of the aging process. It has a rich, concentrated miso flavor, so don’t discard it. Simply mix it back into the miso before using.

Does homemade miso need to be refrigerated after fermentation?

Yes, once the miso has fermented to your liking, store it in the refrigerator. This slows down the fermentation and helps keep the flavor stable for longer.

If you have more questions, feel free to leave a comment below!

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