What You Need to Know
Periodic skimming of aerobic fungi (Aspergillus oryzae overgrowth) and wild yeast blooms (Hansenula/Candida species) that compete with Zygosaccharomyces rouxii, preserving the ideal amino acid-to-alcohol conversion ratio.
Critical for preventing excessive esterification or butyric acid development that would create unbalanced umami with harsh alcoholic notes.
Key Parameters
Temperature
25°C
18°C - 30°C
Time
Every 96 hours
Every 72 hours - Every 120 hours
Equipment
Sterilized bamboo skimmersFood-grade silicone scrapersLED inspection lamps (450nm wavelength for mold detection)
Steps
- 1.
Koikuchi Shoyu (Chiba Prefecture): Preserves 1:1 ratio of nitrogen compounds to reducing sugars
- 2.
Saishikomi Shoyu (Yamaguchi Prefecture): Prevents volatile acidity in double-fermented style
The Science
Primary Reaction
Competitive microbial inhibition