Intro to fermentation: How to make your own sauerkraut
In the six years I have been facilitating sauerkraut workshops, there has been a common thread among attendees: most arrive not knowing what to expect, and with a bit of fear about what will come of this experiment. Much of that fear, I believe, has to do with the reputation that accompanies all things fermentation. I hope to dispel any myths by describing what to expect from one of my sauerkraut workshops.
In a typical workshop, I begin by describing my motivations for fermenting vegetables: health, ecology, budget, and community. Then, I describe the stages of the process: chopping the vegetables, massaging them with salt, stuffing the soggy product into a mason jar, and the at-home fermentation. That’s it! Normally I sense a little relief at that point. During the workshop I add some tips and tricks that we will handle as needed.
Here is a quick overview of the process, with complete instructions included below.
The participants stand around Karma’s member room table with a cutting board, a chef’s knife, large bowls, and some combination of cabbage, beets, carrots, turnips, etc. Then, the chopping commences and the cut veggies are placed into bowls. This part of the workshop takes 20–30 minutes.
Massaging the vegetables:
This is the magical moment where the fermentation process begins. Sea salt is added to the bowls full of vegetables and participants then massage the salt into the vegetables until it becomes evident that a sufficient amount of liquid is produced. I once did a workshop for children between 8 and 12 years old along with their parents, and I will never forget the look in one girl’s eyes as she witnessed the water extract from the vegetables. She said, “Mummy, water is coming out and we didn’t add any water.” Intellectually, we know vegetables contain water but it’s another thing to witness it in real time.
Stuffing the soggy mess into a mason jar:
Once the salt has sufficiently extracted the water, we simply stuff the vegetables into a mason jar. When the vegetables are pushed down into the jar, the water rises up and over the vegetables. This provides the anaerobic environment needed for the fermentation to occur.
After finishing the hands-on work, I distribute the handouts. I give a number of pointers for success with the sauerkraut fermentation process, which occurs at home. At this point, some people’s fears come to the surface but with the handout, there is a sense that these fears can be overcome.
Gather your materials:
- Cabbage (purple, green, or a mixture)
- Sea salt
- Extra goodies of your choice (optional; examples include caraway seeds, juniper berries, grated carrot, grated ginger, and countless other possible ingredients and recipes)
- Cutting board & chef’s knife (food processor or mandolin are also options)
- Fermenting container: mason jars with two-piece lids OR crockpot
- Wide bowl (e.g., salad bowl or mixing bowl)
- Mason jar funnel (optional but reduces mess — worth it for $7)
- Tamper device of your choice (e.g., Vitamix tamper, potato masher, or big spoon)
- Ladle or large spoon (to scoop and transfer cabbage)
A note on using clean containers (mason jars, crockpots, or other) for the fermentation process: You must clean the containers thoroughly prior to fermentation. Fermentation containers can be reused but should be cleaned before each use. They do not necessarily require the sterilization that the canning process calls for, but the containers should be clean. Also note: if using mason jars, replace the lids if they become rusty.
Prepare and massage the cabbage:
1. Chop cabbage:
a. Rinse cabbages thoroughly & remove outer leaves (save for later).
b. Chop cabbage to medium-small pieces and remove the core (save for later).
2. Massage cabbage:
a. Put chopped cabbage in the bowl and add sea salt with the following ratio: 2 to 3 tablespoons of sea salt (30 to 45 mL) for every 5 pounds of cabbage.
b. Massage until water of cabbage is sufficiently removed. Salt water should accumulate and you should now have a soggy cabbage (note how much the volume of cabbage decreases).
TIP: If massaging is tough for you, try this:
Do the massage up to a point of around 5 minutes, and let the bowl sit for 1 to 6 hours. When you return to continue massaging, time will have helped you a lot as it softens on its own, and from there it is easier to squeeze to the point of being done.
3. Transfer cabbage to fermenting container:
The goal is submersion!!
a. Transfer the cabbage into the jar (with any optional ingredients) while using a tamper device as needed to push cabbage down tightly to get the water level to rise.
b. Keep filling. When you get near the top, add the outer cabbage leaves and core that you saved earlier to ensure total submersion. Finally, put the lid on. The finished jar should have all your fermenting cabbage submerged under the salt water.
Remember to leave air space!
After the workshop — at home
VERY IMPORTANT— Submersion: As the days of your fermentation go by, note that the cabbage should be submerged under the saltwater to ensure it ferments and avoids mould. In most cases, this requires no action. In the case that your salt water level seems to be a little below the cabbage, top it up with some more salt water.
VERY IMPORTANT— The temperature should be within or very close to the range of 15°C to 21°C, which likely is the case in your home for a good part of the year. You may need to find a cool spot if your home gets very warm.
VERY IMPORTANT— Gas pressure buildup: Note that if you use a crockpot designed for fermentation, there is no need to account for gas pressure building up because a release valve is built into the container. However, when using mason jars, because we tighten the lid firmly to avoid mould, it is necessary to burp the jars to release the pressure once or twice a day during fermentation (especially from days 2 through 5). This is very important to prevent exploding jars and/or leaking. PROACTIVE BURPING IS THE BEST INSURANCE AGAINST EXPLODING GLASS!
Frequently asked questions
1) What exactly does burping mean? How do I do it?
The lid remains tight during the fermentation, but gas is produced inside the jar. Burping means opening the lid for a brief time to allow air to escape, and then tightening it again. Burping can be anywhere from 2 seconds if it is a mild burp to 2 minutes if the jar needs more time to release the built-up pressure. Keep the jar open only for the needed time to allow air to escape and tighten as soon as possible to avoid mould.
2) What location should I choose for my jar to ferment?
Remember the temperature range required for fermentation to be successful is 15°C to 21°C. This is a cool room temperature. Avoid locations near heat sources like heating vents and stoves. Avoid locations too cool in your living space like next to a cold exterior wall. Avoid direct sunlight on your jar, although room light is ok. Darkness is ok, but not required. If you choose a dark location, like in a cabinet, be sure to set up reminders to burp the jars frequently and avoid exploding jars.
3) I am concerned about how much gas will emerge from my jar when I burp it?
The recommended process is to place the jar in the sink and then burp. Also, a good optional tip is to use a dry rubber dish glove to burp. It makes it easier to grip a tight lid when attempting to open it, and it prevents spraying around of gas and liquid.
4) When I burp the jar, the fizz and gas and water spills into my sink. Is that a problem?
It’s no problem. In this case, your jar had a lot of gas to release. Scoop out the fizzy bubbles from the top and give the jar up to 2 minutes to breathe.
5) Even if I burp the jar frequently, some liquid is leaking out of the lid as it sits tightened during fermentation. What can I do about this?
Rather than placing it directly on the counter, place it either on an old rag or inside a non-metal bowl (a glass or plastic bowl will work).
6) Even if I burp the jar frequently, I’m still worried about even the slightest chance of glass exploding. For example, what about children or pets coming near the jar? Is there anything else I can do to prevent an explosion?
Ok. Safety first for sure. One tip here is that while your jar sits in the bowl or on the cloth, cover it with an old kitchen towel or cloth and weigh it down a bit to limit how far glass can disperse. Keep the jar located in a convenient place so you will remember to burp it and check on it, but make sure it is far enough away to ensure safety. Some people have had success with placing the jar in a sealed box or inside a cabinet. Again, if you proactively burp and you leave enough air space at the top of the jar, the probability of a jar exploding is very low.
7) You told me that my cabbage should remain under the salty water and now, during the fermentation, but it seems that the water is below the cabbage at the top of the jar. What should I do?
Remove any dried, discoloured leaves or any leaves showing signs of mould growth. Then, add back enough salt water to cover the cabbage, while leaving a reasonable air space. Mix your salt water using this ratio: 1.5 tablespoons of salt per litre of water.
8) I burped my jar and noticed mould on the surface of the water line and on the lid. What should I do?
Sometimes this happens and naturally occurs during some ferments. Do not throw it all away. Scrape away any mould (white fuzz or small pieces of cabbage that turned blackish colour above the water line). Continue to monitor for any mould as the days go by. The cabbage under the water is protected by extremely strong acidity.
9) I burped my jar and it smells like someone took the garbage out three days ago and then brought it back inside. Is this a problem?
It is understandable that the smell of fermentation may turn some people off. Let’s deal with this, as first impressions are very important. While we should respect our smell senses to tell us if food is ok or not, we should also keep in mind that on health journeys there is plenty of room to change and broaden our senses and tastes. For countless generations, our ancestors smelled the same scents that we smell today and went on to safely enjoy their fermented foods. Consider that it is quite possible to reject a smell at first and, given enough patience, later enjoy a safe and delicious food.
10) The cabbage core we used at the workshop is not submerging the cabbage under the water as much as I would like. It is moving around too much or it looks like a little mould is on it. What should I do?
You have options. Try another piece of vegetable from your fridge that can substitute for this purpose, OR, remove the cabbage core and carefully use a clean, glass shot glass or other clean, small object instead. Just make sure the shot glass is strong and sturdy and that you are careful as you press it down and place the lid over it. Glass can break so only do this if you are confident about doing it.
11) How do I know the ferment is happening as I move into days 2, 3, 4, and beyond?
1. Burping your mason jars is evidence as you hear the gas pressure release: bubbles from the carbon dioxide are often noticed and you will get the feeling that you are witnessing biochemistry in action, as though a living active process is under way. Some ferments have more subtle gas buildup and bubbles, while others are more dramatic.
2. Colour change often happens and you may wish to take a picture on day 1 and compare to a later day.
3. The ultimate way you know that the ferment has been successful is your taste intuition. Taste your sauerkraut after 6 or 7 days, and if you like it, simply put it in the fridge. If you taste it at that point, and your body tells you a little more time is needed, give it another 3 to 5 days, and then put it in the fridge. Whenever you do your taste tests, you will look for your personal sense of the sour, crunchy taste of sauerkraut. Less fermenting time will yield a more subtle taste. If, for example, you taste it after 14–16 days, and you prefer that, it suggests you prefer a stronger, more sour sauerkraut.
12) How do I know the fermentation is complete and what do I do with it once it is complete?
No perfect answer to how long it takes. Consider the three points mentioned above as principles. Variables such as room temperature mean that there is no specific rule. For the sake of this workshop and the first time doing this, you cannot go wrong with considering your ferment complete anywhere between 6 days and 14 days. Notice that by day 6 or 7, the gas pressure in the jar will be zero or close to zero, which indicates that the necessary chemical process has essentially happened by that point. Once the fermentation is done, the sauerkraut goes in the fridge or cold room. Now you have a preserve of a minimum of 6 months and many people feel it lasts a lot longer.
13) OK. The time has come for my first taste and even after reading all of the above and following the instructions, I am still scared. How can I trust putting this new type of food in my mouth?
No one other than you is the final arbiter as to what you eat. Remember though, we are eating a time-tested food. Remove any parts of the cabbage we used to submerge the water like the core and big outer cabbage leaves. Scoop a small amount of sauerkraut out from under the water and eat on an empty stomach, and pay attention to your body in the next little while. If you still feel scared, connect with someone experienced with ferments, and have your first tasting with them.
14) I heard someone made their own home-made sauerkraut, ate it, and felt sick to their stomach afterwards. Does that mean it’s risky?
Do not automatically assume the problem is with the sauerkraut. Sure, follow the instructions above to get the process right. That said, this brings up a good point. This is a powerful, non-pasteurized ferment loaded with beneficial bacteria. Depending on the individual, it can be challenging to handle too much of this goodness all at once. If someone’s digestive system is out of balance, a big serving can cause a die-off response (like a detox) and that can feel yucky to say the least. If this happens to you, instead of swearing off sauerkraut, consider it an important learning opportunity. If you are unsure how you may react to this food take the patient approach. Have your first serving be 1/2 a teaspoon. Then, see how it feels as you try to gradually build up to 2 tablespoons per serving and so on.
15) My sauerkraut has now been sitting in my fridge or cold room for a little while and the water level has dropped quite a bit below the top of the cabbage and it even looks like there is little water left.
Quite normal. Once it is in the fridge, the water level sometimes remains high and sometimes goes down. It is still perfectly fine either way. It still preserves for many months. Notice that once it is in the cold temperature, no signs of mold occur, even if the water level goes down.
submitted By Leor Israelski