For many of us, Sauerkraut is the gateway drug... the ferment we learn and love first. It's the blank canvas on which we master the manipulation of salt, time & temperature, grow in confidence, and experiment with flavour. Sauerkraut is the most classic example of the 'dry-salt' method of fermentation and a brilliant place to start (in the same way as the Dill Pickles are a great first example of the brine method of fermenting).
A 'recipe' feels too clinical for kraut, instead, here's an explanation of the principals and method.
For the dry salt method we work with a ratio of 2%. The process is a case of finely chopping and shredding cabbage, weighing it, and then sprinkling it with the appropriate amount of salt. 1kg shredded cabbage needs 20g flakey sea salt, for example. Be sure to weigh after chopping, not the whole cabbage!
Don’t throw away the ‘butt’ of the cabbage – this will come in handy later!
Rather than adding water to make a brine, begin to scrunch and/or pound your cabbage. I like to work as if I'm kneading dough - it can feel very therapeutic. Not only is the salt is abrasive, but it also naturally draws water content from the cabbage. After a few minutes of squeaky 'kneading' the cabbage will be sopping wet, swimming on its own natural juice.
As ever, it's important to work cleanly so do clean your Kilner jar well - here's how the pros recommend doing it. And now simply pack your limp and sodden cabbage (ugly words - sorry!) down into the jar, compressing it well to force out any air pockets. Fill it to the neck of the jar if possible, and pour over all the excess liquid; it's important that all the cabbage is submerged under the water line, as this is the right environment for the good bacteria (the lactic acid bacteria) to grow.
I mentioned to hold onto the ‘butt’ of the cabbage… Trim the butt of the cabbage so it fits neatly within the neck of the jar, covering the surface. Ideally, when the lid is closed it will compress the ‘butt-bung’ and forced everything underwater. If your bung needs a little extra height to meet the inside of the lid, use an off-cut of the cabbage core on top of the ‘butt-bung’.
Exactly how long to leave your sauerkraut fermenting depends on the temperature of your kitchen, and your personal preference in both in texture and acidity... A shorter ferment at room temperature (4-7 days) will yield milder and crunchier sauerkraut, a longer ferment at room temperature (anywhere from 7-14 days) will yield a softer and tangier kraut. Over the last two years, having become more accustomed to the flavours of fermentation, my preferences have shifted from the former to the latter. I recommend tasting the kraut every other day and observing the changes – it’s a fascinating process!
After two days you will start to see some activity around the neck of the jar, some fizzing and burbling..! In winter, be wary of central heating, and try to keep the kraut somewhere with a fairly consistent temperature. The jar will need ‘burping’ each day – do this in the sink! When you are happy with the flavour profile, pop it in the fridge where it will last indefinitely.