The reason you only need salt and cabbage to create sauerkraut is that the bacteria we need are naturally occurring in cabbage (and cucumber), which means you don't need to use a starter culture when using it (although this doesn't hurt).
To do this simply chop your cabbage and place with salt in a large bowl, and then wash your hands and start squeezing the cabbage. When crushing the cabbage by hand (hard) you will notice a crackling noise, which is the internal structure of the plant being crushed. This has several effects:
- Firstly, it releases water from the cabbage, which mixed with the salt creates the brine,
- Secondly, it makes it easier for the bacteria to act because the cell walls also be broken during this process
- Finally, you will know when you have crushed the cabbage sufficiently as the crackling sound will lessen considerably and the cabbage will become quite wet after a few minutes.
I have noticed that older cabbages tend not to have as much water in them, but I have not yet needed to add salted water to the brine when using this technique.
Many people use an implement to pound their sauerkraut rather than crush it by hand - this can work just fine, but I prefer using my hands, as it is far easier to ensure you are crushing all the cabbage consistently and avoid over bruising some bits while leaving others untouched.
