Although many of us think of European cuisines when we dig out the sauerkraut, in fact, sauerkraut is thought to have been around for thousands of years as cabbage was fermented in rice wine in China. If you like to buy in bulk or you are lucky enough to dig up plenty of cabbages in fall then along with canning, freezing is another way to extend the shelf life of sauerkraut.
So, the definite answer to the question, can you freeze sauerkraut is yes, you can, and it may keep for up to 12 months in the freezer. However, be aware that refrigerated sauerkraut will keep for around six months and over time, frozen sauerkraut can lose some of its texture and maybe even some of its flavor.
If you would like to freeze some sauerkraut, then continue reading to find out exactly how to freeze it, whether store bought, homemade or even cooked up in soup or with pork.
How Long Can You Keep Sauerkraut in The Refrigerator?
It is important to keep store bought and homemade sauerkraut refrigerated to reduce the risk of spoilage. If you buy sauerkraut in cans, then once you open the can, tip the contents into a clean airtight container or jar before refrigerating. If you leave the sauerkraut in a can it will only keep for around a week in the refrigerator once opened.
Otherwise, sauerkraut should keep for around six months if kept in the coldest part of the refrigerator and the lid of the container or jar is left tightly fastened after use.
Can You Freeze Store Bought Sauerkraut as Well as Homemade Sauerkraut?
Sauerkraut does have a decent shelf life in the refrigerator but apart from this, the only other ways to store it for any length of time is by canning or freezing. Although canning will allow sauerkraut to keep for a couple of years, the heating process required for safe canning means there is loss of probiotic bacteria in the sauerkraut, whereas as you will see in the next section, some probiotics can survive the freezing process.
If you want to freeze either store bought or homemade sauerkraut, it is always best frozen at its freshest. If you are freezing homemade sauerkraut, then you should be freezing it on the day, or soon after, that you have made it. If you have bought some from the store, then be ready to freeze it within a couple of weeks of you first opening the container or can. Depending on the container it comes in, you may also need to transfer it to something more suitable for the freezer. If your sauerkraut comes bagged, check the bag before freezing as it may not be suitable to use in the freezer.
How Do You Freeze Sauerkraut?
The best type of sauerkraut for freezing is one with little liquid. If you have a lot of liquid in a sauerkraut, drain the excess with a sieve before freezing. The less liquid there is, the less chance there is of the cabbage becoming too mushy after thawing. Sauerkraut can keep for as long as 12 months in the freezer however it may lose some of its texture and its flavor may be a little milder as the fermentation is stopped due to the freezing.
Sauerkraut is best frozen in smaller portions as it will not keep for long after thawing. To do this, use an old ice cube tray or muffin tin and once frozen, move the cubes into an airtight container or freezer bag. Otherwise, place the sauerkraut into suitable freezer bags and remove the excess air before freezing.
You can also use good quality freezer containers, just leave a gap of around half an inch at the top of the container to allow any expansion during the freezing process. Remember to note the date of freezing on the bag or container before you freeze it.
How Do You Thaw Sauerkraut?
Probably the easiest way to defrost sauerkraut is overnight in the refrigerator. Once sauerkraut has been thawed in the refrigerator, it can be kept for up to four days before it should have been used or disposed of. If you want sauerkraut straight away for your sandwich or burger, then use the defrost setting on the microwave. Just run the program in 10-15 second bursts and check the sauerkraut after each burst to see if it is defrosted. If you defrost it in the microwave you must eat it straightaway – it cannot be put in the refrigerator for using at a later date.
If you want to use the sauerkraut in soups, casseroles and other cooked recipes, then drop frozen sauerkraut straight into the pan and allow it to defrost during cooking. You may need to add a little extra cooking time to make sure it is properly thawed and heated.
Can You Freeze Sauerkraut and Pork or Sauerkraut and Kielbasa?
If you have leftover sauerkraut and pork then yes, you can freeze it. It is best frozen as soon as it is cool. You can freeze it either in an airtight container or ziplock bag. If you use a bag, remember to remove as much air as you can from the bag before sealing it shut. Before you freeze the sauerkraut and pork, drain off any excess liquid and if there are a lot of leftovers, you may prefer to split it down into smaller portions for freezing.
The best way to reheat frozen sauerkraut and pork is either in the oven or fry pan.
You can freeze sauerkraut and kielbasa in exactly the same way as sauerkraut and pork but when you come to reheat, you may want to leave it to thaw at room temperature for an hour as this means there will be less risk of it burning when it is reheated.
Can You Freeze Sauerkraut Soup?
Of course you can freeze sauerkraut soup but do not add dairy ingredients such as sour cream before freezing as this will not freeze and thaw as well. If you make sauerkraut soup with large chunks of vegetables, you may also lose some of the texture. Slightly undercooking vegetables for freezing in soups can help stop them being as mushy once thawed.
Does Freezing Sauerkraut Kill Probiotics?
Sauerkraut is fermented through a process called lacto-fermentation and it is this that gives sauerkraut its distinctive flavor. The surface of the cabbage (and other vegetables and fruits) is home to Lactobacillus - ‘good’ bacteria. When these bacteria are covered in a salt brine, they convert the sugars in the cabbage to lactic acid. This stops other ‘bad’ bacteria from being able to multiply and spoil the food.
These ‘good’ bacteria, also known as probiotic or ‘live’ bacteria are the same bacteria found in yogurt and they help support our gut health. Although there is debate around how much benefit is lost from probiotics with temperature changes, freezing will kill some of the probiotic bacteria off, but others will freeze and remain dormant until the sauerkraut is thawed. These can then resume their activity.
If you freeze sauerkraut that has been cooked, such as with pork, then yes, the process of cooking and then freezing will more than likely kill off all of the probiotic bacteria.
So, there is a risk that freezing sauerkraut may kill some of the probiotic activity, but if you have a lot of sauerkraut then it is still worth freezing some to keep it for a later date – especially if you have a shortage of refrigerator space!
How Do You Make Sauerkraut?
If you have never made sauerkraut, then it is worth trying it as it usually tastes much better than store bought! There are plenty of recipes available but here is a basic recipe which uses 1½ lbs. of green cabbage and ¾ tablespoon of kosher salt. You can also add caraway seeds for extra flavor.
You will find it easier using a large mason jar which will need to be ‘weighted’ during the fermentation process to hold the cabbage down. You can make a wight by filling a small jelly jar with marbles.
Before you make the sauerkraut, give everything a good wash with soap and rinse well to remove any trace of soap. Your hands should also be thoroughly clean. After washing the cabbage, trash the outer rough leaves (except for one) and slice the remainder into ribbons.
Place the cabbage in a bowl and sprinkle the salt on the top. Start to rub the salt in and squeeze the cabbage with your fingers. Taking around 10 minutes or so, the cabbage will start to resemble coleslaw. If you want at add caraway seeds or other spices, then these can be added now.
Transfer the cabbage to the mason jar and every so often, push the cabbage down hard with your fist. Once the bowl is empty, pour any leftover liquid over the cabbage. You can now add your leftover cabbage leaf to the top of the cabbage where it will be a float to place your jelly jar weight on. Also be prepared to tamp it down by hand frequently at first to stop the cabbage from floating.
Now cover the mason jar mouth with a clean piece of cheesecloth or similar and secure with a rubber band. Store it at 65°F to 75°F away from any direct sunlight.
If by the following day, liquid is not covering the cabbage add some extra liquid (dissolve a teaspoon of salt in a cup of water) to fully cover it. If you see any mold on top of the cabbage, it can be skimmed off along with the cabbage near the surface and disposed of. The rest of the cabbage will be fine. Mold will grow when cabbage is not fully submerged in the brine.
The fermentation will only take a couple of days for a small amount but the longer you leave it to ferment, the better it will taste. When you are happy with its taste, remove any scum from the top of the sauerkraut, add the lid to the jar and transfer to the refrigerator. This should keep for at least a couple of months.
In Summary – Freezing Sauerkraut
In this post I have explained how you can freeze sauerkraut successfully for up to 12 months, whether the sauerkraut is fermented or cooked. Although sauerkraut will keep in the refrigerator for up to six months, freezing sauerkraut is an ideal way to store some of that bulk buy or even homemade sauerkraut – especially if you are running out of room in the refrigerator.
Unlike canning, sauerkraut which is frozen can keep some of its probiotics although it will start to lose some of its texture and even a little of its flavor the longer it stays in the freezer.