What is miso paste?
Miso paste is a traditional Japanese seasoning produced by the fermentation of soya beans, salt and koji (Aspergillus oryzae). The fermentation process can take anywhere from a few weeks to several years. The result is a thick, aromatic paste with an intense umami flavour, which plays a central role in Japanese cuisine.
Origins and history
The origins of miso stretch far back into the early Asian fermentation tradition, which is closely linked to China and Korea. Buddhist monks brought this knowledge to Japan, where, over the centuries, miso developed into a culinary staple in its own right.
Originally, miso was used as a method of preserving protein sources. Over time, however, it evolved from a mere preservation method into a seasoning in its own right with a complex flavour profile.
Today, miso is an integral part of everyday Japanese cuisine and, at the same time, a fermented product appreciated worldwide.
The basis: fermentation with koji
The production of miso relies on the enzymatic activity of koji (Aspergillus oryzae). During fermentation, this mould breaks down:
- starch into sugar
- proteins into amino acids
This creates the characteristic umami flavour that gives miso its depth and complexity.
How is miso made?
The production of miso is a slow, microbiologically controlled process that requires traditional craftsmanship and patience.
1. Preparation of raw materials
Soya beans are soaked and boiled to break down their protein structure. Depending on the recipe, rice or barley is used as an additional source of carbohydrates.
2. Koji production
The prepared ingredients are inoculated with koji spores. During the maturation phase, the fungus produces enzymes that later facilitate the fermentation process.
3. Fermentation (Moromi-like phase)
The mixture of soya beans, koji and salt is processed into a thick paste. This matures in barrels or tanks over a period of months to years.
During this time, the following are produced:
- amino acids
- organic acids
- flavour compounds
- umami compounds
Fermentation proceeds slowly and continuously.
4. Maturation
Maturation plays a decisive role in determining the umami flavour, colour and intensity. Longer fermentation results in darker, more robust varieties of miso.
The production of miso is considered resource-efficient, as fermentation requires little energy and plant-based raw materials are utilised efficiently.
Furthermore, miso is made from soya beans, which have a smaller ecological footprint compared to animal proteins.
Many producers are increasingly turning to organic and sustainable farming practices.
The different varieties of miso
Miso is divided into different categories depending on the raw materials, fermentation duration and degree of maturation. These differ significantly in colour, flavour and intended use.
- Shiro Miso (白味噌): Shiro Miso has a short fermentation time and a mild, slightly sweet flavour. It usually contains a higher proportion of rice koji and is suitable for: dressings, light soups or marinades. It is the most approachable and delicate variety.
- Aka Miso (赤味噌): Aka Miso matures for significantly longer and has a more intense, saltier flavour profile. Its darker colour results from longer fermentation and more pronounced Maillard reactions. Typical uses:stews, hearty soups or savoury sauces. It delivers a deep, dominant umami flavour.
- Awase Miso (合わせ味噌): Awase Miso is a blend of Shiro and Aka Miso. It combines mild and robust notes, making it particularly versatile.
- Hatcho Miso (八丁味噌): Hatcho Miso is the most intense traditional variety. It is made almost exclusively from soya beans and undergoes an extremely long fermentation process. Characteristics: very dark, thick consistency and extremely strong umami. Ideal for hearty stews and concentrated sauces.
Miso paste is far more than just a seasoning paste. It is a deeply rooted fermented product that combines tradition, microbiology and culinary art. From simple soups to modern fine dining, miso delivers an unrivalled depth of umami and remains one of the most versatile fermented foods in the world.
Discover our miso products
Discover the range of organic miso from Mimi Ferments in Berlin, where traditional Japanese craftsmanship meets innovative maturation in fine wooden barrels! These organic misos offer an extraordinary spectrum of flavours, ranging from mild and slightly sweet to deeply savoury umami, all of the highest artisanal quality.
Shiro Miso
The award-winning organic Shiro Miso paste from mimi ferments is characterised by its particularly mild, fruity-sweet flavour with subtle notes of apricot and Parmesan. What makes it special is its high proportion of koji rice and a short maturation period of just two months in ashwood barrels. This allows the white miso to retain its light colour and a subtle, delicate aroma, which clearly distinguishes it from stronger, darker pastes. Find out more about our Shiro Miso
Ama Miso
Our Ama Miso, an organic rice miso, impresses with it has a pleasantly sweet flavour and balanced umami, accompanied by elegant, savoury aromas. During the 12-month maturation in red wine barriques, subtle malt notes unfold with a hint of dried fruit. This miso is versatile and ideal for sauces and soups. Find out more about our Ama Miso
Ama Mugi Miso
This organic barley miso captivates with a full-bodied, savoury flavour featuring a delicate sweetness and malty notes of prunes. A particularly high proportion of barley koji gives it a gives it a particularly pronounced aroma. After twelve months’ maturation, despite its barley base, it has a laboratory-tested, very low gluten content (under 100 ppm). Find out more about our Ama Mugi Miso
Genmai Miso
Genmai Miso is an organic miso made from sprouted wholegrain rice and a high proportion of soya. It is characterised by an intense, meaty and savoury flavour. After two years’ maturation in red wine barriques, it develops a powerful umami with malty and toasty notes, as well as subtle hints of black olives. It owes its characteristic dark brown colour and flavour complexity to the particularly long fermentation period. More about our Genmai Miso
Health benefits
Miso paste is rich in nutrients and offers a wide range of health benefits. It contains a high concentration of proteins, vitamins and minerals, which are important for a balanced diet. Of particular note are the B vitamins, which play a key role in energy metabolism and help maintain a healthy nervous system.
Another major benefit of miso paste is its probiotic content. These beneficial bacteria support digestive health by promoting a balanced gut flora. A healthy gut flora can also strengthen the immune system. Studies have shown that regular consumption of fermented foods such as miso paste can reduce the risk of certain chronic diseases.
Furthermore, miso paste contains antioxidants, which help to neutralise free radicals in the body. Free radicals are unstable molecules that can cause cell damage and are linked to ageing processes and various diseases. By eating foods rich in antioxidants, such as miso paste, you can support your long-term health.
Discover more articles: