Sauerkraut is a fermented food made using cabbage. The fermentation process can take upwards of six weeks and is achieved by slicing the cabbage into strips and submerging in a salty brine. Canning food is a perfect way to utilize seasonal foods and high-yield gardens and turn that abundance into a long-term food supply.
How To Can Sauerkraut
Learning How to Can Foods
As incredible as that sounds, canning requires some skill and knowledge. This article is less about how to can and more about how to find inspiration in preserving foods through canning. If not done correctly, canning can be dangerous. If you want to learn to can food, then you should take a class or course or learn from someone who can physically go through the process with you. You can find courses through local community colleges and sometimes through small garden farms or cooperatives.
I can an amazingly wide variety of foods and come from a long line of people who can food from everything from vegetables to meat and albacore. It is a remarkable way to preserve food, but it must be done correctly to be safe.
The process for canning sauerkraut begins with fermenting the cabbage. Once the sauerkraut has fermented, you can either use the Raw Pack method or the Hot-pack method. We will talk about both of these a little later in the article.
Tools Needed for Canning Sauerkraut
- Water Canner – Sometimes called a boiling water canner. This is a specialized pot with a wire rack in the bottom and a fitted lid. These are not pressure canners.
- Quart or Pint canning jars, lids and rings – For about 25 pounds of cabbage expect to produce 6 quarts of sauerkraut or about 12- pints.
- Canning funnel – This is a wide mouth funnel that fits nicely into canning jars.
- Several clean, dry towels. I prefer the cotton flour sack towels for canning.
- Jar tongs for removing or placing the jars into the hot water bath.
- Clean cloth for wiping the mouths of the jar before putting the lids and rings.
*Note: this is assuming that you have made sauerkraut. If not, you will need to make sauerkraut first.
These are all the tools that you will need to can most things, including sauerkraut.
The Canning Process. – Raw-Pack vs. Hot-pack
The difference here is the item being canned and when it is added to the jar. Raw-packed food is as the name implies, not cooked. The food is added to the canning jars while it is cold or at room temperature. With the hot-pack method, the food is heated to near-boiling but never boiled. Once it begins to simmer, it is added (hot) to the jars.
Why would you use one method over the other? The filled jars require less processing time in the water canner when you use the hot-pack method. For sauerkraut that would 15 minutes in the water bath for quart jars using the hot-pack method vs. 25-minutes of processing for the raw-pack method – also for quart jars. Some foods also are easy to work with cold or hot. Jam, for instance, is best canned using the hot-pack method so that the additives are liquified before being added to the jars.
Note: the processing time is different based on the jar size.
Filling the Jars
You always start with sterilized jars and clean lids and rings. Lids are never used twice, but out of the box they must be washed in warm soapy water. For canning to be safe, you must start with a nearly sterile environment inside and outside of the jars. This is also why the food mixture is boiled or processed in the water bath. Because the jar is sealed, the environment remains free of harmful bacteria. The acidity of the food also plays a part in keeping food safe as bacteria (by species) grow in certain environments. This is why high acidic foods have a longer shelf life than do canned foods that are lower in acidity.
Whether you use the raw-pack or the hot-pack method, the jars must be filled. To do this, use the canning funnel. It too must be sterilized or at the bare minimum washed in hot soapy water. I prefer the metal canning funnels over the plastic one as they can be boiled. I use a stainless-steel wide mouth funnel. For sauerkraut, each jar needs to be filled to ½ inch from the top. That space at the top of the jar is called headspace, and there is a bit of science to why this is very important.
Headspace is the space in a filled jar from the lid to where the liquid or food level is. This is such a standard procedure that canning jar manufacturers have designed a built-in way to measure headspace. Even so, you should check the measurement before you trust the jar. The rings on the jar where the lid-ring twists onto the jar are measured for you. From the top, the first ring is ¼ of an inch. The middle is at ½ inch, and the base of the bottom ring is 1-inch. There are also gadgets that will measure this for you and also help you to remove any air bubbles in the jar.
The headspace for sauerkraut is ½ inch. Other foods will have a different requirement for headspace. Jam, for example, only needs ¼ of an inch of headspace. Canned meat, for example, will need 1-inch of headspace.
The amount of headspace has to do with how likely a processed jar of food will seal. Certain types of foods swell or plump as they are processed and if they do not have enough headspace in the jar to accommodate that the food will be forced out of the jar and the lid will not seal. When you open a canned jar of food, there is a little hiss that tells you the jar is sealed. The amount of headspace in the jar is also about how much air is forced out of the jar during the processing time. That action helps to form a vacuum within the jar that helps to keep the jar sealed. There is a chemical, physical, and environmental set of processes that occur. The chemical is the rubber lid adhering to the glass. The physical is the pressure exerted by the ring on the lid to help hold it in place, and the atmospheric or environmental is all about headspace, temperature, and processing time. All three of these things come together to help the canning process to work. Therefore, the amount of headspace in the jar is important and also why it changes from one food type to another.
Fermented sauerkraut is its own preservation method, but it may only last several months in the fridge. This is why we can it. The canning process allows the fermented sauerkraut to remain safe for 1-2 years. The exact time depends on how you store the jars. My rule of thumb is to use high-acid foods within a year from their canning date, and that is a rule that I have built into my food management plan.
Planning for Canning
Generally, five large heads of cabbage will produce around 25-pounds of usable product. I plant 20-30 cabbage plants five of which go into making sauerkraut. The remaining cabbage I use fresh or in other canned or fermented projects. Five heads of cabbage make about 12-pints of sauerkraut. That equates to about one pint per month. Once opened it lasts nearly a week. This is why I can sauerkraut in pint jars rather than quarts.
A Note about Fermenting Foods
The process works because the brine prevents most harmful bacteria from forming. Fermenting cabbage is an ancient technique, and it is found in many cultures around the world. For example, the Koreans ferment cabbage to make Kimchi – a hot and spicy fermented cabbage snack or side. Many of us have had fermented foods, such as traditionally fermented pickles. All these options for fermenting foods use a process called Lacto-fermentation. That process uses beneficial bacteria, found naturally in some foods, to convert the lactic sugars and other natural forms of sugars into lactic acid. That acidic brine helps keep food safe to eat so long as the food remains submerged in the acid.
Fermented foods are a very healthy part of a good diet. Several studies point to the role of fermented foods in the natural production of probiotics. The roughage in fermented foods is a platform on which beneficial bacteria colonize our gut. That process is referred to as prebiotic. There are additional studies that link lacto-fermenting bacteria to improved gut health, improved immune system support, and potentially even as a mechanism that prevents inflammation.
Is it worth learning to ferment food?
Absolutely. You need only pickling salt, water, and a crock with a lid to ferment food. Fermented foods range from beer to cheese, and most of us are used to eating things like sourdough bread or yogurt. Well, you can make fermented pickles, kimchi, and fermented juices and kombucha. Even without canning, this is a technique for preserving food and an art form that every prepper should know. Fermented foods can often be canned to extend their shelf life, and they are an easy way to deal with an over-producing garden. If you have extra cucumbers but don’t have time to can them (canned pickles) you can ferment them in very little time. If you have an extra head of cabbage and nothing to do with it, you can make kimchi in very little time.
David Stillwell is a lifelong naturalist with a background in healthcare and biology who lives in the heart of wildfire territory in Northern California. Prepping for him is a way of life and necessary on a daily basis. He focuses on food production and agriculture and grows 80% of what he consumes.