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Fennel and lemon sauerkraut
Level 1 · beginner
White cabbage with thinly sliced fennel and the zest and juice of a lemon. The fennel brings a gentle anise aroma and the lemon, a citrus note.
- Salt
- 2.5% 25 g per kilo of vegetables
- Time
- 3–4weeks
- Temperature
- 70–75°F
- Jar
- 1L
The golden rule: keep everything under the brine and never use less than 2% salt.
No sign-up. We guide you step by step, from the scale to the fridge.
Reviewed October 26, 2026 · 35 facts, each with its source
You'll need
- 1-liter glass jar (about a quart)
- Glass weight, or a sealed freezer bag filled with brine
- Airlock lid, regular lid or a cloth
- Kitchen scale
Step by step
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Shred the cabbage, slice the fennel and zest the lemon
Wash the jar, the weight and the bowl in hot soapy water and rinse them well. Remove the outer leaves, quarter the cabbage, cut out the core and shred it finely. Cut off the fennel stalks and remove the outer layer if it's tough or bruised. Halve the bulb, cut out the hard core at the base and slice it very thin. Zest the lemon without reaching the white pith, which is bitter, and squeeze out its juice. Weigh everything together: the salt is worked out from that weight.
Tip: A mandoline slices the fennel as thin as the cabbage.
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Mix in the salt and massage
Sprinkle the salt over the vegetables and squeeze them with clean hands until they release their juice. Add the spices and aromatics at the end and mix everything together.
Tip: If no juice comes out, let the vegetables sit with the salt for a while and squeeze again.
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Pack the jar until the juice covers everything
Pack the vegetables in layers, pressing down until the juice covers them. Pour over whatever is left in the bowl and leave room at the top: in the first days it rises and gives off gas.
Tip: If the juice doesn't cover it, add brine of about 28 g of salt per liter of water, boiled and cooled.
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Add the weight and close the jar
Set the weight so everything stays under the brine and close the jar whichever way suits you. With no weight, a zip-top freezer bag filled with brine and sealed does the same: it fits the mouth of the jar and, if it leaks, does not dilute the salt. You can also press food-grade plastic wrap onto the surface and set the weight on top. At 70–75 °F it's usually done in 3 to 4 weeks; colder, it takes longer. It's fermented when the bubbling stops.
Close it the way you prefer
- Airlock lid
- Lets the gas out without letting air in: nothing to do.
- Regular lid
- Close it, and each time you check on it, loosen it for a moment to let the gas out. Close it again right away.
- A cloth
- No lid: the weight on top, everything under the brine, and the jar covered with a clean cloth. Check it 2 or 3 times a week and lift off any white film.
Tip: Mold needs air: anything below the brine is protected.
No sign-up. We guide you step by step, from the scale to the fridge.
Variations
The same method, a different flavor. Once you have this one down, try one of these.
What you'll see
Fennel, sliced thin and mixed with the cabbage, gives the kraut a gentle anise aroma and a little crunch. The zest and juice of a lemon make it fresher. Use an unwaxed lemon, since the peel goes in. It takes the same salt as a plain cabbage kraut: 25 g for every kilo of everything that ferments, lemon included.
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How to tell it's going well
- Never less than 2% salt, by the weight of everything that ferments. Cutting the salt in a vegetable ferment is not safe.
- Everything under the brine, from start to finish.
- Fuzz or green, blue, brown or black spots: that's mold. Throw out the whole batch; it can't be scooped off.
- A white, gray or pink film: usually kahm yeast. Lift it off now and then.
- A putrid smell: throw it out. Well fermented, it smells clean and sour.
- Below pH 4.6, the limit the guides set. We suggest waiting for 4.2 before the fridge.
Where every number comes from
Every number in this recipe comes from a food safety guide. We keep a copy of each source and quote its exact words.
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1
Shredded vegetables are dry-salted; chunks go in brine
“Liquid brines are usually used for fermenting chunks, whereas salt is directly mixed with shredded or minced foods like sauerkraut.”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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2
25 g of salt per kilo of vegetables
“2.5% 25 g / kg food”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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3
Tested recipes range from 2 to 10% salt
“Tested recipes will fall between 2% and 10% brine concentrations.”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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4
It is not safe to cut the salt
“It is unsafe to reduce salt in lactofermented vegetables.”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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5
Salt without additives, such as canning salt
“The salt used in fermentation should contain no additives. Canning or pickling salt is recommended”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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6
Salt is best weighed
“It is best to weigh salt for accuracy.”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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7
The freshest vegetables you can get
“Use the freshest produce possible”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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8
Non-iodized salt
“Be sure to use non-iodized salt.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
Show the remaining 27 claims
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9
A one-liter jar holds about 950 g of dry-salted vegetables
“Remember, a 1-quart jar will hold 2 pounds of veggies when dry salting, and 1 pound when adding a brine.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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10
Everything washed in hot soapy water and rinsed well
“Wash all surfaces and containers that will be used with hot sudsy water and rinse well before use.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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11
The airlock lets the gas out
“it is important to vent the jar with a one-way valve to release the gases that form during fermentation.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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12
Without an airlock, loosen the lid now and then
“If a one-way valve is not used, the gases will need to be released manually by loosening the lid occasionally.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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13
Salt draws the juice out of the vegetables
“Pack firmly until salt draws juices from cabbage.”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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14
If the juice doesn't cover them, boiled and cooled brine
“If juice does not cover cabbage, add boiled and cooled brine (1-1/2 tablespoons of salt per quart of water).”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
-
15
3 to 4 weeks at 70–75 °F
“At temperatures between 70º and 75ºF, kraut will be fully fermented in about 3 to 4 weeks”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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16
Below 60 °F it may not ferment; above 75 °F, it softens
“At temperatures lower than 60ºF, kraut may not ferment. Above 75ºF, kraut may become soft.”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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17
Once fermented, it keeps for months in the fridge
“Fully fermented kraut may be kept tightly covered in the refrigerator for several months”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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18
Check it 2 or 3 times a week
“you will have to check the kraut 2 to 3 times each week and remove scum if it forms”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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19
It's fermented when the bubbling stops
“until normal fermentation is completed (when bubbling ceases)”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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20
Plate, weights and a clean towel
“Add plate and weights; cover container with a clean bath towel.”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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21
Everything under the brine
“All produce should be submerged in the brine liquid.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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22
Mold needs air
“Molds require oxygen to grow.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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23
If there's mold, the whole batch goes
“If you confirm mold growth on any part of a ferment, it should be immediately discarded.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
-
24
Mold is usually green, blue, brown or black
“Mold is typically green, blue, brown, or black in color.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
-
25
A white film is usually kahm yeast
“This film is typically yeast, often referred to by home fermenters as Kahm yeast.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
-
26
Kahm is lifted off now and then
“For other ferments, such as sauerkraut, yeast should be periodically removed during fermentation.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
-
27
A putrid smell means a failed ferment
“A putrid smell indicates a failed fermentation.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
-
28
It smells pleasantly sour, not putrid
“A fermented fruit or vegetable will smell pleasantly sour but not putrid.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
-
29
Bubbles are a good sign
“Some fermentation microbes make carbon dioxide gas during the fermentation process. This can be a good sign”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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30
The pH must not rise above 4.6
“The pH can be checked periodically to ensure it does not rise above 4.6.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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31
Mold can't be scooped off
“The mold cannot be scooped out, as the roots will still be in your food and could make you sick.”
Ask Extension (Clackamas County Extension, Oregon State University) · Pickle/olive brine surface mold spots #889210 · read on October 20, 2026
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32
Open the lid only briefly
“The lid should only be opened briefly to limit oxygen from entering the container.”
University of Minnesota Extension · Preserving food at home: Fermentation (reviewed 2026) · read on October 25, 2026
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33
The bag holds brine: if it leaks, the salt is not diluted
“It is recommended that the brine solution be stored in plastic bags to ensure that the fermentation brine is not diluted should the bag leak or break.”
Virginia Cooperative Extension (Virginia Tech) · Vegetable fermentation (FST-328, reviewed 2025) · read on October 26, 2026
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34
The bag, well sealed
“Be sure to seal the plastic bag.”
National Center for Home Food Preservation (USDA, University of Georgia) · Suitable Containers, Covers, and Weights for Fermenting Food · read on October 26, 2026
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35
Plastic wrap on the surface, weighted down
“covered with food grade plastic wrap and weighted down with water on top of the plastic.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.2: Sauerkraut (2024) · read on October 26, 2026
