National mold
Koji and fermentation
The figure
Miso — 10–12% salt
Miso runs 10–12% salt. Salt here is not seasoning — it is the speed control on fermentation.
Washoku is a fermented cuisine
If dashi is the skeleton, the fermented seasonings are the blood. Soy sauce, miso, mirin, vinegar, sake — koji works first in all of them.
Lactic acid bacteria, yeasts and acetic acid bacteria are everywhere. What is Japanese is putting koji at the centre. Its enzymes cut protein into amino acids and starch into sugar; the bacteria add acid and the yeast adds aroma.
Salt is a number for the microbes
Rice miso runs about 10 to 12 per cent salt. Too little and it rots; too much and everything stops. The salt is not there for flavour — it sets the speed.
Grilled fish at 2% of its weight, miso soup at 8–10% of the dashi, clear soup at 0.6–0.9%. This cuisine is made of numbers first. The instinct arrives later.