- Cutting board
- A jar made out of either glass or earthenware (like a ceramic crock) (you can also use food-grade plastic if you must)
- A rock, or small jar that fits in the bigger jar, or plastic bag
- Square of cloth to cover mouth of bigger jar (optional)
- Rubber-band to hold cloth over mouth of jar (optional, but highly recommended)
- Cabbage (preferably organic and locally grown) (about 2.5 lbs. of cabbage should render about 1/2 gallon/2 liters of sauerkraut, so plan your jar size accordingly)
- Sea salt (or any type of salt except chemically iodized salt)
A word on lacto-fermentation and ingredients: Sauerkraut depends on the action of bacteria present on the leaves of cabbage to provide the pickling magic, and you want to encourage them as much as possible. Pesticides may kill or restrict these naturally-occurring bacteria, which means the sauerkraut may not pickle if using non-organic cabbage. Similarly, iodine definitely kills bacteria and that's why I suggest not using iodized salt.
A word on checking cabbage for bugs: One of the methods the OU recommends for checking cabbage is to peel off the first few layers of leaves (approximately six leaves) and check each leaf on both sides under a bright light for bugs. If only one or two bugs are found among all those leaves, the rest of the head may be used without checking "provided the remaining leaves of the head are very tightly packed together." If three or more bugs were found, it's necessary to check an additional layer. If that one is clean, you're good to go without further checking. But if more bugs were found there (which is highly uncommon), it's necessary to check the whole head. (The OU Guide to Checking Fruits, Vegetables, & Berries, 2nd Edition, Orthodox Union 2007, pp. 21-22)
- Chop the cabbage in half from top to bottom and cut out the core. You can eat the core right now if you want... it's crunchy and tastes fresh and usually a little spicy, kind of like kohlrabi, or you can shred it and throw it in with the sauerkraut. Or you can throw it in the compost bin, as you prefer.
- Shred the cabbage. You can achieve this a number of ways. I often just use a knife and chop the cabbage into the smallest pieces I am able. You can also use a hand grater, and grate the cabbage to the grade you like. Or, the fastest and easiest method is to shred with a food processor. Use what is available to you or what you prefer, and gather the shredded cabbage into a bowl.
- Add salt to the shredded cabbage at about a 1:1 ratio, one tablespoon of salt per head of cabbage. It doesn't really matter whether you're using large or small cabbages because about one tablespoon of salt will be fine for either. Mix the salt and shredded cabbage well.
- You will notice that the mixture is starting to get wet. This is very good. The salt is beginning to extract juice from the cabbage leaves, and that juice is essential to the sauerkraut-making process. You need to rough up the cabbage a bit at this point. Punch it and knead it for a couple minutes like you would to bread dough. This aides the juice-extraction process.
- Start transferring the shredded cabbage mixture to your jar. As you fill in every couple inches, give it a good few punches. Some people use a wooden tool instead of a fist to do this packing down, which is easier and more convenient, unless you don't have such a tool.
- Once all your cabbage is packed in, or the jar is getting full (remember that you will need to leave enough headroom for the liquid to rise, and for a weight, and a little airspace under the optional cloth cover), you need to use something heavy to weigh down the cabbage and make sure it remains under the liquid which will be extracted. This can be achieved a number of ways. You can use a rock (make sure you wash and boil it first), or a smaller jar filled with water, or a plastic bag filled with water (or create your own method). Either way, the point is that when the salt extracts enough liquid from the cabbage, you want the cabbage to remain submerged under the liquid, and the weight will do this. The worst thing that will happen if the cabbage floats to the top and is exposed to air is that the top layer will get moldy, and even then, you can just remove that top layer and eat what's underneath it.
- Let it sit with the weight on about twelve to twenty four hours, and check to make sure enough liquid has been extracted. There should be about an inch or two of liquid above the cabbage. If there is not enough liquid to cover the cabbage, add a well-dissolved mixture of water and salt at about a 1:1 ratio, one tablespoon salt to one cup water.
- If you want, attach the cloth cover with rubber-band and let it sit in a cool, dark place for between two weeks to three months. You can taste it as it ages, and when it tastes best to you is when it's ready. At least visually check it every few weeks to make sure too much water hasn't evaporated, otherwise the cabbage will become exposed. The cloth cover is optional, but I think it's a good idea just to keep out dust and bugs.
- When it's done, you can move the whole jar into the refrigerator, or pack the finished product into smaller jars and refrigerate those, and then start a new batch in the big jar. The refrigeration essentially freezes the fermentation process where it is, although it is actually still occurring at a much slower pace. This sauerkraut should be fine for at least six months to a year, if not longer.
- You can mix in liquid from old batches of sauerkraut into new batches, which is not necessary but it acts as an inoculation of the new batch.
- When you get comfortable with sauerkraut making, you can get creative with ingredients. Some traditional and modern sauerkraut flavorings include: apples, fennel, juniper berries, seaweed, and hot peppers. You would add these flavorings at the beginning of the fermentation process.
- Like the ecosystem in a forest or meadow, different communities of bacteria "rise and fall" the longer the sauerkraut ages. Like Sandor Katz says, "Bacteria called Coliform start the fermentation. As the Coliform produces acid, the environment becomes more favorable for Leuconostoc bacteria. The Coliform population declines as the population of Leuconostoc builds. As acids continue to be produced and the pH continues to drop, Lactobacillus succeeds the Leuconostoc. The fermentation involves a succession of three different types of bacteria, determined by the increasing acidity." (Katz, Sandor. Wild Fermentation, p. 40)