Miso paste - What are they, and how are they different?

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What is miso bean paste?

Miso, or みそ/味噌 is a traditional Japanese fermented food that is produced from the process where grains like soybeans, rice, or barley are mixed with salt and malt. It is used as one of the seasonings in a wide variety of Japanese dishes.

Its main ingredient is soybeans, but it is classified into so many categories depending on the grains or malt used during the process. Its taste differs from region to region.

Soybeans are mixed with malt and salt to get themselves fermented. By this fermentation process, the protein contained in the soybeans gets decomposed so that it becomes more digestible, and during this process, amino acid, which is the source of ‘umami’ taste, gets liberated. 

Classifications of miso

The taste of miso differs depending on the types of malt used, malt-to-soybean ratio, and salt content.

Miso can mainly be classified into four types based on the malt used in the process. Out of these four types, about 80% of miso sold in the market in Japan is Rice-malt miso.

  • 米みそ: Rice-malt miso
  • 麦みそ: Barley-malt miso
  • 豆みそ: Soybean miso (the only ingredients are soybeans, salt, and water)
  • 調合みそ: Compounded miso (two, or three types of the above miso are mixed)

Then, they are further classified into the below categories based on taste and colours:

By taste By colour
  • Low-sodium miso (減塩みそ)
  • Sweet miso (甘口みそ)
  • Dry-taste miso (辛口みそ)
  • Reddish-coloured miso (赤みそ)
  • Light-coloured miso (淡色みそ)
  • White-coloured miso (白みそ)


Let’s have a look at the below table to know the characteristics of different types of miso.

Malt Classification by teste and colours Malt-to-bean ratio Salt content
Rice Low-sodium-sweet 2:1 5-7%
1.5:1 5-7%
Sweet 1.2:1 7-12%
1.4:1 11-13%
Dry-taste 0.6:1 11-13%
0.6:1 11-13%
Barley Sweet 1.7:1 9-11%
Dry-taste 1:1 11-13%  
Soybeans 100% beans 10-12%

*Table quoted from: https://www.chuokai-yamagata.or.jp/s-miso/qa/miso/05.html

  • Malt-to-bean ratio:

The more the malt content is, the richer the sweetness from the rice/barley and the fragrance of the malt becomes. If the amount of the beans used in the miso paste is more than that of malt, you can taste the umami flavour of the soybeans as well as the saltiness from the salt.

  • White-coloured miso:

White-coloured miso is produced with a short fermentation process. The taste is less salty compared to reddish-coloured miso. You can taste the sweetness that is produced by the malt.

  • Reddish-coloured miso:

Reddish-coloured miso is produced with a long fermentation process. It is salty and has a deeper taste.

How miso is made (case of rice-malt miso)

The below process is quoted from Marukome miso, one of the biggest manufacturers of miso in the market.

  • Wash soybeans

After the wash, the soybeans are soaked in water overnight. Once the size of the soybeans becomes twice as big, drain the water and warm up the soybeans.

  • Steam and simmer the soybeans

First, soybeans are steamed in a short time under high pressure and high temperature.

  • Mash the soybeans

Mash the soybeans thoroughly to make it easier for them to get fermented.

  • Mix the soybeans with other ingredients

Mix the mashed soybeans with rice-malt, salt, and “seed water*”. Mix them thoroughly. 

*About 50% of miso consists of water, and water which is added for moisture adjustment is called “seed water”. Soybean broth can be sometimes used as “seed water”.(https://www.pref.saitama.lg.jp/b0901/sai-misodukuri.html

  • Prep the thoroughly-mixed mixture for the fermentation process

  • Fermentation and aging process

Letting the prepped miso ferment and age. In a few months, flavourful aged-miso will be born.

Tips for choosing the miso you want

Knowing the characteristics of the ingredients will help when choosing miso you want. (https://kakakumag.com/food/?id=12107 )

  • Rice-malt miso(米みそ):

  • Barley-malt miso(麦みそ):

  • Soybean miso(豆みそ):

Miso products on the market

  • Additive-free miso (無添加)
  • Miso paste combined with soup stock (だし入り)
  • Liquid miso (液みそ)

* Liquid miso is a new type of miso, which is easier to use and store compared to the typical paste types. According to the survey Marukome conducted in 2020, 89.9% of the people surveyed use the liquid type while they combine it with the paste type. 38.5% of the participants use different types of liquid miso depending on the food they make.

Want more product information from Marukome? Visit their website

  • Miso produced by Aka Marusou, an Okinawan company

Want to know more about their products? Visit their website

Their online shop


The local company Aka Maruso provides some recipes on their website. You can find the recipes here. Although the recipes specify their products to be used for their recipes, you can play with the recipes by trying different miso or mixing different miso, etc.