Usukuchi Shoyu (Light Soy Sauce) (淡口醤油)
The pale soy sauce of the Kansai region - lighter in colour than koikuchi, but not lighter in salt.
| JAS type | Usukuchi ('light mouth'), centred on Tatsuno, Hyogo, in the Kansai region |
|---|---|
| Colour vs salt | Paler than koikuchi, yet typically a little saltier - its job is to season without darkening the dish |
| Use | Clear soups, simmered vegetables, egg dishes - Kansai cooking where ingredients keep their colour |
Usukuchi exists for colour control. Kansai cooking prizes the natural colours of ingredients, so brewers mature this type for a shorter time and sometimes add a sweet rice ferment to keep it pale - while keeping the salt high enough to season properly.
The common beginner's error is to use it as a 'low-salt' soy sauce. It is the opposite: use slightly less than koikuchi, and choose it when a dark sauce would stain a light dish. For low-sodium needs, look instead for products labelled gen-en (salt-reduced) within the koikuchi type.
See also
KoikuchiRelated page in this guide.Substitutions: what works
Related page in this guide.
Sources: Ministry of Agriculture, Forestry and Fisheries (MAFF), 'Traditional Foods in Japan'; JAS soy sauce standards; Umami Information Center; Kikkoman official information; Wikipedia (CC BY-SA 4.0). Checked 6 November 2026.