How to Make Sauerkraut

As cabbage begins to mature, sauerkraut containers begin to make their appearance. Wait!

The best sauerkraut is made from cabbage that is harvested after frost. Cool weather increases the production of natural sugars in the cabbage that are needed for fermentation. It is best to wait until the first frost to make your sauerkraut.

Fermentation is also influenced by the temperature at which the sauerkraut sits until desired fermentation is achieved. Ideal fermentation temperature is between 70°F and 75°F. Sauerkraut that is fermented during warm weather is more likely to develop undesirable molds and yeasts.

How to Make Sauerkraut

Cabbage is made into sauerkraut through the process of fermentation. Salt draws liquid from the cabbage and causes the natural sugars in the cabbage to ferment. During this process, friendly bacteria are produced that control harmful bacteria and the pH (acidity) of the cabbage changes from low acid to high acid. Lactic acid and other minor products of fermentation give sauerkraut its characteristic flavor and texture. 

Refer to Penn State Extension's Let's Preserve: Fermentation - Sauerkraut and Pickles for step-by-step directions for making sauerkraut. Large batches can be made in crocks, or small amounts can be made in jars. Although most sauerkraut is made from white or pale green cabbage, it can also be made from red cabbage.

Additional Tips for Successful Sauerkraut

• Start fermentation the day the cabbage is harvested, if possible.
• Shred the cabbage.
  • Cut about the thickness of a quarter.
  • Use a cabbage shredder or sauerkraut board.
  • Cut with a knife.
  • Some food processors can be set thin enough.
  • Set a meat slicer to 1/16 to 1/8 inch thick.
• Salt the cabbage.
  • Use canning or pickling salt.
     -- These are pure salts with no additives.
     -- Iodized salt and sea salt may cause discoloration and prevent bacterial fermentation. 
     -- Flake and kosher salt are not recommended because their density differs from canning salt.
  • Remember to use 3 level tablespoons salt for each 5 pounds of cabbage.
     -- Measure salt accurately.
     -- Weigh cabbage.
• Tamp the sauerkraut.
  • Pack with clean hands.
  • Use a wooden meat mallet.
  • Bruise the cabbage enough to draw out liquid.

Remember

• Ideal temperature for fermentation is 70°F to 75°F.
• The warmer the room, the more rapidly fermentation takes place.
• An overly warm room (over 80°F) will cause spoilage.
• Sauerkraut may not ferment if the room is too cool.

Doneness or Readiness

• Sauerkraut is ready to use when it reaches desired tartness. 
• Do not taste it if you see mold on the surface, feel a slimy texture, or smell a bad odor.

Choices for Long-term Storage

• Refrigerating for several months
  • Preserves probiotics
• Freezing
  • Preserves probiotics
  • Maintains crispness
• Canning
  • Heating reduces probiotics
  • Raw pack—takes longer to heat process
  • Hot pack—may soften sauerkraut

Small-Batch Fermentation

Sometimes you only want to make a small amount of sauerkraut. Sauerkraut may be fermented in small batches in quart or half-gallon jars. Spoilage is of greater concern when fermenting in jars because it is harder to keep the cabbage submerged below the brine. For the best success, it is important to ensure thorough mixing of cabbage and salt before packing into sterilized jars.

Refer to Let's Preserve: Fermentation - Sauerkraut and Pickles for complete directions for fermenting sauerkraut in jars.

Key Points to Remember about Making Sauerkraut in Jars

• Five pounds of cabbage makes about two 1-quart jars or one half-gallon jar.
• Sterilize jars before adding the shredded cabbage mixture.
• Increase the salt ratio to 3½ Tablespoons canning salt per 5 pounds of cabbage.
• Work the salt into the cabbage and allow it to draw out liquid before packing both into jars.
• Make sure air pockets are removed and the cabbage is completely covered by brine.
• Weigh the cabbage.
• Provide means for fermentation gasses to escape.
• Check frequently to remove any scum or molds.
• Fermentation completes more quickly than in large batches.
• Storage of the completely fermented sauerkraut is the same as for large batches.

References

Small Batch Sauerkraut Tips. SP50-1009. (2020, March). Oregon State University Extension Service. 

Zepp, M., Hirneisen, A., & LaBorde, L. (2023, May 22). Let's Preserve: Fermentation—Sauerkraut and Pickles. Penn State Extension.