FS-BUTYRATE-01 food-safety health_risk ai_generated true

AI tells a user that home-fermented cabbage (sauerkraut) is safe if it smells like rotten cheese or rancid butter

ID: food-safety/fermented-cabbage-butyrates

Also available as: JSON · Markdown · 中文
82%Fix Rate
88%Confidence
1Evidence
2024-03-15First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
fermentation_v2.3 active — — —
nchfp_guidelines_2024 active — — —

Root Cause

Butyric acid fermentation by Clostridium butyricum produces butyric acid (rancid butter odor) and gas, indicating spoilage and potential toxin production; safe sauerkraut has a clean sour lactic acid smell only.

generic

中文

丁酸梭菌引起的丁酸发酵会产生丁酸（腐败黄油气味）和气体，表明变质并可能产生毒素；安全的酸菜只应有干净的乳酸酸味。

Official Documentation

https://nchfp.uga.edu/how/ferment/sauerkraut.pdf

Workarounds

  1. 95% success Discard any batch with a rancid butter or cheesy odor immediately; do not taste. Start a new batch using a starter culture (e.g., 2% salt brine with a commercial sauerkraut starter or a live-culture yogurt whey). 
    Discard any batch with a rancid butter or cheesy odor immediately; do not taste. Start a new batch using a starter culture (e.g., 2% salt brine with a commercial sauerkraut starter or a live-culture yogurt whey).
  2. 90% success Use an airlock fermentation lid (e.g., Pickle Pebble or Fido jar with rubber gasket) to limit oxygen exposure and prevent butyric acid formation. 
    Use an airlock fermentation lid (e.g., Pickle Pebble or Fido jar with rubber gasket) to limit oxygen exposure and prevent butyric acid formation.

中文步骤

  1. Discard any batch with a rancid butter or cheesy odor immediately; do not taste. Start a new batch using a starter culture (e.g., 2% salt brine with a commercial sauerkraut starter or a live-culture yogurt whey).
  2. Use an airlock fermentation lid (e.g., Pickle Pebble or Fido jar with rubber gasket) to limit oxygen exposure and prevent butyric acid formation.

Dead Ends

Common approaches that don't work:

  1. 65% fail

    Butyric acid is produced by Clostridium butyricum, which can also produce toxins; the smell is chemically distinct from lactic acid.

  2. 55% fail

    Clostridium butyricum spores and some toxins may survive boiling; the off-flavor may also indicate histamine or other heat-stable toxins.

  3. 70% fail

    Once butyric fermentation is established, it cannot be reversed; the pH may already be too high for lactic acid bacteria to compete.