What You Need to Know
Aspergillus oryzae molds produce amylases (α-amylase, glucoamylase) and proteases (acid protease, neutral protease) that hydrolyze starches into glucose and proteins into amino acids including glutamic acid. Lactobacilli (Tetragenococcus halophilus) and yeasts (Zygosaccharomyces rouxii) subsequently develop, lowering pH to 4.7-5.0.
Creates the umami foundation for soy sauce through glutamic acid production while developing complex flavor precursors like 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF).
Key Parameters
Temperature
30°C
15°C - 40°C
Time
6 months
3 months - 24 months
Equipment
Cedar fermentation vatsCeramic vesselsStainless steel tanks (modern)
Steps
- 1.
Shoyu (Japan): Primary fermentation stage for standard soy sauce
- 2.
Tamari (China): Wheat-free variant with thicker moromi
The Science
Primary Reaction
Proteolysis