Name: Short Miso (60-day Shiro)
Cook time: 60 d
Cuisine: Japan

Short Miso (60-day Shiro)

Short-aged 'white' miso (shiro): cooked soybeans + koji rice + salt, fermented 2-6 months. Mild, sweet-umami, light yellow color. Longer-aged variants (aka, hatcho) go 1-3 years. Distinct from other ferments: requires koji culture, much higher salt, much longer ferment. Classified separately because timescale is different.

Salt %: 6.00%
Primary: 60.0 days
Secondary: 120.0 days
Temperature: 65-75°F (18-24°C)
Vessel: ceramic crock or food-grade bucket

Technique

Requires koji (Aspergillus oryzae inoculated rice) — buy or cultivate. Cook soybeans until mashable. Ratio by weight: 1 part soybeans : 0.5-1 part koji : 0.1 part salt (that's 6% salt by total solids + 6-10% moisture). Combine, mix thoroughly, pack tight in crock pressing out air. Top with sterilized weight + plastic sheet. Seal. Ferment 65-75°F for 60+ days. White miso is ready at 60 days; red miso at 6-12 months; hatcho at 1-3 years. Stir once at 30-day mark to redistribute moisture.

Source: NYT Cooking — homemade miso (David Chang adapted).

Run the math: salt % · brine · temperature timing