What You Need to Know
The process relies on high salt concentrations (~20–25 % w/w) to inhibit spoilage bacteria while permitting halophilic microbes to hydrolyze fish proteins into peptides and free amino acids, especially glutamic acid, which imparts umami flavor. Proteolysis is accompanied by lipolysis of fish fat, releasing free fatty acids that contribute to aroma. The fermentation is largely anaerobic, limiting oxidation of lipids.
The Science
Primary Reaction
Proteolysis and lipolysis of fish proteins and fats by halophilic microbes under high-salt, anaerobic conditions