Sauerkraut Fermentation at 18°C (65°F)
At 18°C (65°F), sauerkraut ferments slowly, developing complex flavors over 3-4 weeks. This cooler temperature is ideal for a crisp, nuanced kraut.
Minimum
14 days
Optimal
21 days
Maximum
28 days
Fermentation Timeline
Initial fermentation begins. Brine starts to cloud.
What to look for:
- Brine becoming cloudy
- Small bubbles appearing
- Slight sour smell beginning
Action: Ensure cabbage stays submerged. Check daily for any floating pieces.
Active fermentation. Bubbling increases.
What to look for:
- Steady bubbling visible
- Sour smell more pronounced
- Brine very cloudy
- Slight tang when tasted
Action: Continue to monitor. Press down weight if cabbage rises.
Fermentation slows. Sourness develops.
What to look for:
- Bubbling decreases
- Consistent sour taste
- Cabbage softening slightly
Action: Taste daily to monitor sourness level.
Maturation phase. Flavors deepen.
What to look for:
- Minimal bubbling
- Complex, tangy flavor
- Pleasant sour aroma
- Crisp-tender texture
Action: Taste test. Move to cold storage when desired flavor is reached.
Extended fermentation for deeper flavor.
What to look for:
- Very tangy taste
- Softer texture
- Richer color
Action: For strong sauerkraut, continue. Otherwise, refrigerate.
Taste Progression
| Day | Flavor |
|---|---|
| Day 3 | Mild, slightly salty, fresh cabbage taste |
| Day 7 | Light tang beginning, still mostly fresh |
| Day 14 | Noticeable sourness, pleasant tang |
| Day 21 | Well-developed sour flavor, complex taste |
| Day 28 | Strong sour flavor, deep fermented taste |
Safety Notes
Important
- Always keep cabbage submerged under brine
- Use a 2-3% salt ratio by weight
- Discard if you see fuzzy mold (not flat kahm yeast)
- The sour smell is normal; foul or rotten smell is not
- White film (kahm yeast) can be skimmed off
Frequently Asked Questions
Why ferment at 18°C (65°F)?
Can I ferment sauerkraut faster?
How do I know when it is done?
Other Temperatures
Complete Sauerkraut Guide
Learn everything about making sauerkraut at home
Disclaimer
This content is for educational purposes only and is not medical advice. Fermented foods affect individuals differently. Consult with a healthcare provider before making significant dietary changes, especially if you have health conditions. Practice proper food safety when fermenting at home.