What You Need to Know
During fermentation, halophilic bacteria such as Halanaerobium and Tetragenococcus hydrolyze fish proteins into free amino acids and peptides, generating glutamic acid and 5′‑inosinic acid that give the sauce its umami flavor. The high salt concentration suppresses pathogenic bacteria while the gradual pH drop to 4.0–5.0 further stabilizes the product.
The Science
Primary Reaction
Proteolysis of fish proteins by halophilic microorganisms producing free amino acids and peptides