What You Need to Know
Hishio involves Aspergillus oryzae (麹菌) and halophilic bacteria breaking down proteins into glutamates (umami) and carbohydrates into simple sugars. Fish enzymes (endogenous proteases) accelerate autolysis.
Served as both condiment and protein source, often diluted into soups or used to preserve vegetables.
Key Parameters
Temperature
20°C
10°C - 30°C
Time
9 months
3 months - 3 years
Equipment
Unglazed ceramic jars (tsukemono ki)Straw-weighted wooden lidsStone pressers
Steps
- 1.
Hishio-jiru (Ancient Yamato court): Diluted as soup base with wild herbs and tofu
The Science
Primary Reaction
Proteolysis → free amino acids (especially glutamic acid)