Description
Miso is produced by fermenting soybeans with Aspergillus oryzae and Bacillus subtilis under controlled temperature and salt conditions, yielding a complex matrix of peptides, amino acids, and flavor volatiles.
Technical
During fermentation, Aspergillus oryzae secretes proteases that hydrolyze soy proteins into peptides and free amino acids, while Bacillus subtilis contributes amylases and further proteolytic activity. Lactic acid bacteria lower the pH to 4.5–5.5, inhibiting pathogens and promoting the formation of volatile sulfur compounds such as 2‑acyl‑4‑methyl‑5‑thiazole. The resulting glutamic acid imparts umami, and isoflavone aglycones are released, enhancing antioxidant activity.
Science
Primary Reaction
Enzymatic hydrolysis of soy proteins by Aspergillus oryzae and Bacillus subtilis, followed by acidification by lactic acid bacteria
Sensory Profile
Aroma ()