Sauerkraut

Instructions

Wash and dry a large preserves jar or crock (about 3 litres), a chopping board and any large bowls you plan to use. Quarter the cabbage, cut out the core, and slice the leaves as finely or as thickly as you like.

If you want, bruise the sliced cabbage with a rolling pin or a mortar and pestle to help it release its juice. Layer it in the jar or crock, sprinkling salt between the layers.

Pack the cabbage down tightly, leaving about 1 cm of space at the top, and do not seal the jar. Juice should rise as you press; if it does not, add a little chlorine-free water.

Cover the jar with a clean cloth or cling-wrap and stand it in a bowl or on a plate to catch any overflow. Keep it unsealed during fermentation, because trapped gas can build up and break the jar.

Twice a day, morning and evening, push a long narrow object down into the cabbage to release trapped air. Pour any juice collected on the plate back into the jar.

Keep the temperature steady throughout fermentation, since swings can let the wrong bacteria grow. In winter, if your kitchen is unheated, move the jar to a room with a steadier temperature, such as a bedroom.

Fermentation takes from three days to about a week. When it is done, wipe away any liquid around the jar, close the lid tightly and move the jar somewhere cool, such as the refrigerator, to mature.

The sauerkraut can be eaten after the first week, and it keeps improving with age as the bacteria slowly use up the more complex sugars in the cabbage.