Two ingredients, one jar and two weeks. This is the method published by the agriculture office of the Bodenseekreis district in southern Germany, followed exactly. The cooking is all in the salt and the patience.
Read fermenting vegetables safely before you start. The method below is what makes this safe, and the safety page explains why each step is there.
You need a clip-top jar of about a litre, with a rubber seal, and something clean and heavy that fits inside the neck: a small glass jar, or a freezer bag of water. The office recommends clip-top jars because the seal lets gas out without letting air in.
- Wash the cabbage. Set aside two of the outer leaves to cover the jar later. Cut the rest medium-fine to fine, or shred it.
- Weigh the shredded cabbage and use 2% of its weight in salt: 2 g of salt for every 100 g of cabbage. A medium cabbage of 900 g takes 18 g. Weigh the salt; do not guess it, and do not cut it.
- Mix the salt through and leave it 20 minutes to draw the water out. For crisp kraut, leave it at that. For softer kraut, massage it with your hands until it softens.
- Pack it into the jar a layer at a time, pressing each layer down hard with your fist to push out every air bubble. Fill to about 3 cm below the rim.
- Lay the reserved leaves on top and weigh them down. The cabbage, leaf included, must sit at least 2 cm under the liquid.
- If the cabbage has not given enough juice, top it up with 2% brine: 2 g of salt in every 100 ml of water. Make sure no scraps of cabbage float on the surface, because that is where mould starts.
- Close the jar and stand it on a plate, because liquid will push out during the first week. Leave it at room temperature, ideally 18 to 22 °C, and do not open the lid while it ferments.
- Two weeks is the minimum. That is how long the lactic acid bacteria take to dominate and bring the acidity down far enough to keep out the bacteria that matter (pH below 4.6). After that it goes in the fridge.
Eat it within six months. The leaflet’s own recipe box says two to four weeks at room temperature and about a year. We have followed its method section instead, which gives the two-week minimum and six months in the fridge. That is the more cautious of the two.
If anything grows on the surface, or it smells wrong or turns slimy, read when to throw it away before doing anything else. If you are not sure, the batch goes.
This needs a fridge once it is made. For a van without one, see storing it, and make a small jar you will finish in a few days.
The office suggests eating it raw, so the bacteria stay alive: as a side, in a salad, on a sandwich or stirred into soup. Its brine works anywhere you would reach for vinegar or lemon.
Makes about a litre jar.