Fermentation Off-Flavor & Defect Troubleshooter
Diagnose rotten egg sulfur smells, DMS, stalled fermentations, haze, and harsh fusel alcohols with certified BJCP/WSET resolution steps.
All Defects
Sulfur & Aromas
Oxidation & Contamination
Fermentation Health
Off-Flavors
Clarity & Appearance
Fermentation Health
Stalled Fermentation (Gravity stopped before target FG)
Root Cause
Temperature drop below yeast range, pH drop below 3.2, alcohol toxicity limit reached, or yeast exhaustion.
Step-by-Step Resolution
1. Test pH: if below 3.2, add Potassium Bicarbonate to raise to 3.4 - 3.6.
2. Warm fermenter to 68°F - 72°F.
3. Gently swirl lees without oxygenating.
4. If dead, pitch a starter of EC-1118 or K1-V1116 rehydrated with Go-Ferm.
Prevention Tip: Monitor pH during active primary and keep fermenter in recommended temperature zone.
Fermentation Health
Yeast-Bite / Rubber / Meaty Taste (Yeast Autolysis)
Root Cause
Leaving finished brew sitting on gross primary yeast lees for 3+ months in warm ambient temperatures.
Step-by-Step Resolution
1. Fine with bentonite or activated carbon to absorb meaty autolytic compounds.
2. Blend with fresh young batch to dilute off-flavors.
Prevention Tip: Rack off primary gross lees within 3-4 weeks after active fermentation ceases.