Miso Is Fermented by a Mould, on Purpose
Miso is a Japanese fermented soybean paste. It depends on a cultivated mould called koji.
Miso is a thick Japanese paste made by fermenting soybeans with salt. The fermentation is started by *koji*, a deliberately cultivated mould called *Aspergillus oryzae*, grown on rice or barley. Its enzymes break proteins into amino acids, including the glutamate that gives miso its savoury depth, so the flavour comes from a mould doing its work rather than from any added seasoning. Soy sauce and sake are made with the same organism.
- A fermented paste. *Miso soup.*
- Koji — the mould starter. *Koji.*
- White miso. *Shiro miso.*
- Red miso. *Aka miso.*
- Japanese — *miso*. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | miso | Miso. |
| Compound | miso soup | Miso soup. |
| Related | koji | Koji. |
| Related | umami | Umami. |
| Japanese | miso | Miso. |
- A bowl of miso soup.Food.
- Koji starts the fermentation.Process.
- Glutamate gives the savour.Flavour.
What koji makes
- Miso — fermented soybean paste
- Soy sauce — fermented soybeans and wheat
- Sake — koji converts rice starch to sugar for yeast
- Mirin — a sweet cooking wine
- All four rely on Aspergillus oryzae
Japanese *miso*, recorded in English from the 1700s.
What is koji?
A cultivated mould, Aspergillus oryzae, grown on rice or barley. Its enzymes drive the fermentation of miso, soy sauce and sake.
Why does miso taste savoury?
Fermentation breaks proteins into amino acids including glutamate, the compound behind the savoury taste called umami.