Miso: A Deep Dive into Japan's Favourite Fermented Paste
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You might be thinking, "What is miso?" despite the fact that it is frequently found in restaurants. Soybean paste in hues of red, yellow, or brown. Japanese miso goes by many names and is used in a wide variety of cuisines in the modern culinary world. Even pastries or sauces use it as a "secret ingredient". Use it to give any meal deeper, earthier, umami, or saltier flavours. Let's explore everything there is to know about miso paste.

Miso can be simply defined as fermented soybean paste. But there's a lot more to this unusual substance than meets the eye. A particular mould that grows on rice, barley, or soybeans is also a component of miso. It is also known as Aspergillus oryzae or koji. The enzymes in the koji gradually erode the grains' and beans' structural integrity. Weeks or even years may pass during the fermenting process. The soybeans will be converted into amino acids, simple sugars, and fatty acids after the fermentation process is finished. Miso has been consumed for thousands of years and used to be regulated in Japan. Even today, traditional miso production is regarded as an art form.

The first step in making miso is to soak the soybeans in water overnight. This helps soften the beans and reduce cooking time. The soaked beans are then drained and cooked in a large pot until they become tender. It is important to cook the beans thoroughly, as this helps to break down the proteins and starches in the soybeans, making them easier to digest.

Once the soybeans are cooked, they are mixed with koji and salt. Koji is a special fungus that has been cultivated on grains like rice or barley. It is responsible for breaking down the starches in the grains and converting them into simple sugars that the yeast and bacteria in the miso can feed on. The koji also helps to develop the unique flavour and aroma of the miso.

After the soybeans, koji, and salt have been mixed together, the mixture is transferred to a large fermentation vessel. The vessel is usually made of wood or plastic and has a lid that can be sealed to prevent air from entering. The miso is left to ferment for several months to several years, depending on the desired flavour and texture. During the fermentation process, the yeast and bacteria in the miso break down the complex sugars in the soybeans and grains, producing lactic acid and other compounds that give miso its characteristic taste and aroma.

When the fermentation process is complete, the miso is usually mashed and then packed into jars or tubs for storage. The colour and texture of miso can vary depending on the length of fermentation, the type of soybeans and grains used, and the region of Japan where it was made. Generally, darker miso has a stronger, more pungent flavour, while lighter miso has a milder, sweeter taste.

Types Of Miso

There are many different types of miso available, each with its own unique flavour, aroma, and texture. The main differences between miso types are the ingredients used, the length of fermentation, and the region of Japan where they are produced.

Shiro Miso

Shiro miso, also known as white miso, is a type of miso that is made with a higher proportion of rice koji and a lower amount of soybeans compared to other types of miso. This results in a sweeter, milder taste and a lighter colour ranging from pale yellow to light beige, than other types of miso. Shiro miso is typically fermented for a shorter period than other miso varieties, usually for only a few weeks to a few months.

Shiro miso is commonly used in Japanese cuisine as a seasoning for soups, marinades, dressings, and sauces. It is also often used as a base for miso soup, which is a popular Japanese dish made by adding miso paste to dashi broth along with ingredients such as tofu, seaweed, and green onions.

Due to its mild and sweet taste, shiro miso is considered to be a versatile type of miso that can be used in a variety of dishes without overpowering other flavours. It is also lower in salt than other types of miso, which makes it a good option for those who are watching their sodium intake. Its texture is also usually smoother and more delicate than other miso varieties.

Aka Miso

Aka miso, also known as red miso, is a type of miso that is made with a higher proportion of soybeans and a smaller amount of rice koji compared to shiro miso. It is fermented for a longer period than shiro miso, typically for at least one year, which gives it a deeper, richer flavour and a darker reddish-brown colour.

Aka miso is commonly used in Japanese cuisine as a seasoning for stews, braises, and other hearty dishes. Its bold, complex flavour makes it a good choice for adding depth of flavour to dishes with strong ingredients like meat or seafood. It is also used in miso soup, which is a traditional Japanese dish made by adding miso paste to dashi broth along with ingredients like tofu, seaweed, and green onions.

Aka miso has a higher salt content than shiro miso, which gives it a stronger umami flavour. It is also a good source of protein and essential amino acids. Like other types of miso, aka-miso contains beneficial bacteria that can support gut health and boost the immune system.

Aka miso is darker in colour and has a coarser texture than shiro miso. When using aka miso in recipes, it is important to adjust the amount of salt used in the dish, as aka miso already has a high salt content.

Awase Miso

Awase miso is a type of miso that is a blend of two or more different types of miso, typically shiro miso and aka miso. This combination gives it a balanced flavour and a medium colour that is in between the light colour of shiro miso and the darker colour of aka miso.

The exact ratio of shiro miso and aka miso in awase miso can vary depending on the manufacturer and region of Japan where it is produced. Some blends may also include other ingredients like barley or wheat koji for added complexity.

Awase miso is a versatile type of miso that can be used in a variety of dishes, including soups, marinades, and sauces. Its balanced flavour makes it a good choice for dishes that require a milder miso taste but still benefit from the depth of flavour that miso provides.

Like other types of miso, awase miso is a good source of protein, essential amino acids, and beneficial bacteria that can support gut health and boost the immune system. It is also high in salt, so it is important to use it in moderation and adjust the amount of salt used in a dish accordingly.

Mugi Miso

Mugi miso, also known as barley miso, is a type of miso that is made with barley koji, soybeans, and salt. It is a fermented paste that is typically aged for at least one year to develop its taste. Mugi miso has a deep, savoury flavour with a slightly sweet aftertaste. It is darker in colour than shiro miso and has a coarser texture than other miso varieties. Its taste is stronger than shiro miso but milder than aka miso.

Mugi miso is commonly used in Japanese cuisine as a seasoning for soups, stews, and other hearty dishes. Its robust flavour makes it a good choice for adding depth of flavour to meat and vegetable dishes. It is also used in miso soup, which is a traditional Japanese dish made by adding miso paste to dashi broth along with ingredients like tofu, seaweed, and green onions.

Hatcho Miso

It is a dark, dense miso with a rich, earthy flavour and a distinctive aroma. Hatcho miso is made by steaming and mashing soybeans and then inoculating them with koji mould. The mixture is then fermented for at least two years, but often up to three years or more, to develop its complex flavour. During the fermentation process, the mixture is packed tightly into wooden barrels and left to mature, which gives it its dense, solid texture.

Hatcho miso is primarily produced in the Aichi prefecture of Japan, where it has been made for over 400 years. It is a staple ingredient in local cuisine and is used in a variety of dishes, including soups, stews, and sauces.

Hatcho miso is a good source of protein, essential amino acids, and beneficial bacteria that can support gut health and boost the immune system. Hatcho miso has a distinct umami flavour that is often described as meaty or savoury. It is darker in colour than other types of miso and has a dense, almost fudgy texture. When using hatcho miso in recipes, carefully adjust the quantities to achieve a balanced flavour, as it has a strong and intense taste.

How To Use Miso?

Miso is a versatile ingredient traditionally used in Japanese cuisine, particularly in miso soup, which is made by adding miso paste to dashi broth with ingredients like tofu, seaweed, and green onions. Apart from soup, miso paste can be used in marinades for meat, fish, or vegetables. It can also be used to create dressings and sauces by mixing it with other ingredients such as soy sauce, rice vinegar, honey, and sesame oil. Miso is perfect for adding flavour to stir-fries, creating a rich, umami-packed sauce with mushrooms, broccoli, and carrots.

Miso can also be used in baking, adding a unique and delicious taste to cookies or cakes. When using miso in your cooking, it is important to adjust the amount used to achieve the desired level of flavour. Miso is high in salt, so it should be used in moderation, and the amount of salt used in the dish should be adjusted accordingly. Miso is also a fermented food, containing beneficial bacteria that can support gut health and boost the immune system.

Storage Instructions

It has a long shelf life and can be stored for several months, even up to a year, if stored correctly. To ensure that your miso stays fresh and flavourful, it is important to store it properly.

 The first step in storing miso is to keep it refrigerated. The ideal temperature for storing miso is between 35 and 45 degrees Fahrenheit. This is because miso is a fermented food, and refrigeration helps to slow down the fermentation process, preventing the growth of harmful bacteria. Once opened, the miso should be stored in an airtight container to prevent it from drying out and absorbing odours from other foods in the fridge.

 When storing miso, it is important to keep it away from light and heat, as that can cause the miso to lose its taste and nutritional value. So, it is recommended to store miso in the back of the fridge or in a cool, dark place.

 It's also important to note that the colour of miso will change over time. Lighter miso pastes, like shiro miso, will darken with age, while darker miso pastes, like hatcho miso, will become even darker and more intense in flavour. This change in colour is normal and does not indicate that the miso has gone bad.