Homemade sauerkraut, all salty and sour, is brilliantly easy to make at home. All you need is two simple ingredients: cabbage and salt. And then plenty of time to allow probiotics to do their work, producing a vibrantly complex and delicious food.
What is sauerkraut?
Sauerkraut is a traditional fermented food made by allowing shredded cabbage and salt to ferment over a period of time. After fermenting for a period of weeks or months, it produces a potent sour side dish that is rich in beneficial bacteria.
You’ll find similar dishes made from fermented cabbage, like kimchi and curtido, throughout the world, sauerkraut has its roots in German and Eastern European cooking.
Like most fermented vegetables, it’s easy to make at home and you only need two very simple and inexpensive ingredients: cabbage and salt.
What are the benefits of sauerkraut?
These beneficial bacteria help support gut health and immune system function. They also help to enhance your body’s ability to manufacture and absorb key nutrients (2). Further, they can also help to support your immune system in cases of food borne illness or digestive distress (3).
Beyond support for digestion, sauerkraut and other fermented foods also show promise in supporting blood sugar regulation, metabolic health and cardiovascular health (4). While the mechanism isn’t fully understood, researchers have found that probiotics help to support optimal weight (5,6), but it largely depends on the specific bacteria.
Fermenting cabbage also releases key phytonutrients that support cellular health. Researchers have examined how these nutrients may prove helpful in the battle against breast cancer (7).
Tips for Making Homemade Sauerkraut
It’s really easy to make sauerkraut, but there’s a few things you should keep in mind to make sure that your kraut comes out perfect every time.
- Shred the cabbage very thinly. For the best texture, avoid food processors and cut your cabbage by hand or with a cabbage slicer.
- Flavor it. Once you get the hang of making it, consider flavoring sauerkraut with fruits, vegetables, specialty salts, herbs and spices.
- Keep the cabbage completely submerged in brine. Brine keeps your cabbage safe during fermentation, and less prone to mold.
- Limit airflow. Your sauerkraut should ferment in an anaerobic environment that allows carbon dioxide to escape without letting oxygen in. An airlock or fermentation crock is useful.
- Taste it. After a few weeks of fermentation, your homemade sauerkraut will be ready to try. Taste it periodically to see if it’s sour enough for your liking.
- If it’s too salty, soak it in cold water for 20 minutes to reduce the salt content.
- Watch for signs of contamination. Sliminess, a putrid smell, and visible mold on the cabbage itself are all signs that your sauerkraut has gone bad. It’s best to discard it and start over.
Salt and Successful Fermentation
At its simplest, good homemade sauerkraut needs only salt and cabbage. When it comes to fermentation, salt performs a few important functions.
First, salt helps to create an environment that favors lactobacillus bacteria. Those are the beneficial bacteria that make fermented vegetables both tasty and healthy. It also helps to keep other microbes like mold at bay until your fermentation is well underway. So we use salt for both safety and flavor.
Secondly, salt helps keep your ferments crisp. Without salt, your sauerkraut will become limp and mushy.
How much salt should you use?
Fermented vegetables like cabbage generally do well with 2-3% salt by weight. That means that for every pound of cabbage you use, you should also use 4 to 5 teaspoons salt.
You can also weigh your cabbage using a kitchen scale, and then use 20 to 30 grams salt for every kilogram cabbage.
How to Store Homemade Sauerkraut
Fermentation preserves cabbage and other vegetables naturally. That’s because the lactobacillus bacteria that ferment foods release lactic acid which, like vinegar, preserves foods and keeps them safe for long-term storage.
If you’re making a small amount of sauerkraut, tucking your jar into the fridge is usually sufficient. But if you’re making more than a quart or two, you may need to find other ways to preserve it.
Once you’ve finished making sauerkraut, you can preserve it a number of ways:
- Canning sauerkraut is a popular method, but it’s unnecessary for long-term storage. The high heat required for canning destroys the beneficial bacteria and delicate food enzymes found in sauerkraut. If you’re intent on canning, follow safe guidelines.
- Refrigeration is the easiest and most intuitive way to preserve fermented vegetables. Cold temperatures slow down the fermentation process. Make sure you store your kraut in its brine, and it will keep at least 6 months.
- Root cellars are traditionally used to store ferments and cold-hardy crops. The low, even temperature functions similar to refrigeration and slows down the fermentation process, allowing you to store them at least 6 months.
- Freezing sauerkraut in food-safe containers is another option. Freezing temperatures may damage the probiotics over time and reduce their numbers (8).
How long should you ferment sauerkraut?
When you bake bread or cookies, there’s a clear finish time. Accordingly, you pull them out of the oven when the timer sounds its alarm, or you risk burning them. But with fermented vegetables, there’s much greater nuance.
First, you want to make sure that fermentation has started. So, you’ll want to look for signs of microbial activity. Bubbling and foaming usually begin within about three days, depending on the temperature of your kitchen. And once you see bubbles forming, you’ll know that fermentation is underway.
But how do you know when it’s done?
Fermentation is complete when your sauerkraut tastes pleasantly sour. It should have a sour aroma similar to vinegar, but less pronounced.
So, if you’ve seen signs of active fermentation, like bubbles, and it smells pleasantly sour, it’s safe to eat. You can continue to let it ferment so that it develops a rich, complex flavor and deep sourness. And just transfer it to the fridge when it tastes right to you.
When considering fermentation time, keep the following in mind:
- Colder temperatures cause food to ferment more slowly, so your sauerkraut may take longer.
- Warmer temperatures cause food to ferment quickly, so it might need less time.
- Smaller volumes take less time than large volumes.
Fermentation Crocks, Jars and Other Equipment
When making sauerkraut, you’ll need a container to ferment your cabbage. Because fermentation is an anaerobic process – that is it’s best without the free flow of oxygen, you’ll need an airtight jar or crock. When oxygen flows freely into your ferments, it can cause mold.
Many home fermenters use mason jars, especially when they’re just beginning. But it’s wise to invest in special fermentation equipment for making sauerkraut.
Ideally, your container is a jar or crock that allows the carbon dioxide that builds up during fermentation to escape without letting oxygen in.
How to Make Sauerkraut
If you’re making homemade sauerkraut, you’ll need to start with fresh cabbage. Very fresh cabbage from the garden or farmers market works best because it has a high water content, which means more juice for your brine.
After tossing any bruised leaves into the compost bin, you’ll core the cabbage and then slice it very thinly. Then mix it with salt and let it macerate until it softens and releases its juice.
Then, after kneading or squeezing the cabbage and salt together to fully release the juice, pack it tightly into jars or your crock. Weigh the cabbage down with glass or stoneware weights or a cabbage leaf, seal your crock. Next, let it ferment away from direct sunlight at least 2 weeks for small volumes and up to 6 months for large volumes, depending on how sour you like it.
Homemade Sauerkraut Recipe
For the Sauerkraut
- 2 pounds cabbage (from 1 head)
- 4 teaspoons fine sea salt
- Glass Weights
- Remove any bruised or damaged exterior leaves from your cabbage, and then slice it in half cross-wise. Remove the cabbage's core, and then slice the cabbage into strips no wider than 1/8-inch thick.
- Toss cabbage and salt together in a large mixing bowl and let it rest about 20 minutes, or until the cabbage begins to soften and release a little juice. Then squeeze the cabbage with your hands to to soften it even further, and help it to release more juice.
- When the cabbage has become limp and has released ample juice, transfer it to your jar. Pack the sauerkraut tightly into your jar, using a kraut pounder or a wooden spoon, so that the cabbage continues to release its liquid and no air bubbles remain.
- Continue packing the cabbage into the container until the cabbage is completely submerged by its liquid. Place weights over the cabbage, and then seal the jar with your airlock. Allow the cabbage to ferment at room temperature and away from direct sunlight at least 1 month, or until done to your liking. When the sauerkaut is sour enough for your liking, transfer it to the fridge where it will keep at least 6 months and up to 1 year.
You might also like this recipe …
1,2) Swain, M. R., Anandharaj, M., Ray, R. C., & Parveen Rani, R. (2014). Fermented fruits and vegetables of Asia: a potential source of probiotics. Biotechnology research international, 2014.
3) Johnston, B.C., et al. (2012) Probiotics for the prevention of Clostridium difficile-associated diarrhea: a systematic review and meta-analysis. Annals of Internal Medicine. 157(12), 878-888
4) Kok, C.R. & Hutkins, R. (2018). Yogurt and other fermented foods as sources of health-promoting bacteria. Nutrition Reviews.
5) Sánchez, Marina. et al. Effect of Lactobacillus rhamnosus CGMCC1.3724 supplementation on weight loss and maintenance in obese men and women. The British Journal of Nutrition. 111(8)
6) Osterberg, K. et al. (2015). Probiotic supplementation attenuates increases in body mass and fat mass during high‐fat diet in healthy young adults. Obesity Research Journal.
7) Licznerska, B. E., Szaefer, H., Murias, M., Bartoszek, A., & Baer-Dubowska, W. (2013). Modulation of CYP19 expression by cabbage juices and their active components: indole-3-carbinol and 3,3′-diindolylmethene in human breast epithelial cell lines. European journal of nutrition, 52(5), 1483–1492.
8) HARRISON A. P., Jr (1955). Survival of bacteria upon repeated freezing and thawing. Journal of bacteriology, 70(6), 711–715.