Description
Aspergillus oryzae enzymes hydrolyze rice starches into fermentable sugars during koji production, creating the foundation for miso's umami profile.
Technical
Amylolytic enzymes (α-amylase, glucoamylase) break down rice starch into maltose and glucose, while proteases (acid protease, aminopeptidase) liberate amino acids from soybean proteins, with subsequent Maillard reactions during aging producing melanoidins and pyrazines.
Culinary Significance
Determines miso's sweetness/umami balance and paste consistency, with shorter fermentations yielding lighter, sweeter kome miso versus longer-aged red varieties.
Science
Primary Reaction
Enzymatic Hydrolysis + Maillard Reaction
Parameters
Temperature
30°C optimal
25°C to 35°C range
Time
6-12 months
48 hours – 36 months
Equipment