Description
Multi‑stage thermal and fermentation process that converts fresh skipjack tuna into low‑moisture, umami‑rich katsuobushi.
Technical
The process begins with boiling and steaming to denature proteins and remove fat, followed by inoculation with Aspergillus oryzae at 20–25 °C where proteolytic enzymes hydrolyze proteins into free amino acids, 5′‑inosinic acid, and 5′‑guanylic acid, generating umami. Subsequent smoking introduces phenolic antioxidants, and prolonged sun‑drying reduces moisture below 5 %, concentrating nitrogenous compounds and driving Maillard reactions that produce brown pigments and complex flavor notes.
Science
Primary Reaction
Proteolysis and Maillard browning
Sensory Profile
Aroma ()
smokynuttyumami-richearthywoodymarinecaramelized
Origin & History
Civilization