I was brought up on sauerkraut. My Great Polish Aunt was a specialist sauerkraut maker and I remember us as kids always having it with our meals. The sour flavour comes from the process of lacto-fermentation, similar to the pickling of cucumbers. But instead of soaking the cabbage in a vinegary brine solution, sauerkraut preparation requires only salt and the lactic acid bacteria already present on raw cabbage. Sauerkraut produces amazing amounts of a healthy probiotic that helps with digestion and a healthy immune system.