So you went ham and got a year’s worth of sauerkraut jars.
After all, it’s picked cabbage, what can go wrong?
Well, are you sure you’ve asked yourself a simple question – does sauerkraut go bad?
Because the answer is not as simple as you might think.
But don’t worry. In this article, we’ll go over the shelf life of sauerkraut, as well as on how to properly store it.
Keep reading to find out more!
How Long Does Sauerkraut Last?
First things first, you should know that sauerkraut is sold as either pasteurized or unpasteurized.
Pasteurized sauerkraut is treated with heat before packaging. This is done to kill all the microorganisms inside. It’s the same process milk and juices go through to be able to remain fresh at room temperature.
Since it kills all the microbes that can spoil the product, pasteurization extends the shelf life of sauerkraut. But it also kills all the good bacteria. Most brands add certain probiotics afterward, but they can never be as good as natural probiotics are.
As for unpasteurized sauerkraut, the bacterial cultures are very much alive. This means that the product is constantly fermenting.
The exact shelf life of unpasteurized sauerkraut differs between brands. So for instance, Sonoma Brinery’s products come with a “best by” date of 5 months from manufacturing.
But the brand also claims that, when stored properly, their products can be consumed even after a year or two.
Most unpasteurized sauerkraut products, like those from Pickled Planet and Raw Supercrauts, stay fresh for at least a year.
Since unpasteurized sauerkraut contains live cultures, whether it’s opened or not doesn’t affect the shelf life. But what it does affect is the way you store it.
Unpasteurized products should be stored in the fridge with a sealed lid. If kept open and at room temperature for even a few hours, sauerkraut can start fermenting for the second time, and won’t be as tasty anymore.
Pasteurized sauerkraut also comes with a “best by” date printed on the label, and that’s a good estimate on how long it will keep its optimal quality. Whether you keep unopened packaging in the fridge or pantry, the shelf life is pretty much the same.
Room temperature | Refrigerator | Freezer | |
Unpasteurized | Less than a day | +1 year | +1 year |
Pasteurized (unopened) | Best by + 3-6months | Best by + 3-6months | +1 year |
Pasteurized (opened) | Not recommended | Up to a week | +1 year |
But things are different once you open it. As we already said, the pasteurization process killed all the microorganisms. This includes lactose bacteria. This means there’s nothing inside the product that will keep the fermentation ongoing once it’s opened.
And because of that, pasteurized sauerkraut will last you about a week or so after it’s opened.
If you’re sure you can’t go through the entire packaging within that amount of time, the only option to preserve sauerkraut is to freeze it. That way, it can stay fresh for another year or so.
How To Tell If Sauerkraut Is Bad?
Sauerkraut can easily spoil if you don’t store it properly.
So you’ve just realized that an opened packaging of sauerkraut has been sitting on your counter since this morning?
Then you’re probably wondering if it’s spoiled.
Let’s check for some obvious cues.
The first one is the smell. Since it’s a fermented product, sauerkraut has a rather strong, pungent smell. Depending on the yeast found inside the product, it can smell sour and vinegary or even beer-like.
Sauerkraut can develop a rather off odor, but it doesn’t always have to be a sign of spoilage. Cabbage is high in sulfur, which releases a smelly gas during fermentation. The odor is merely a side effect of a natural process and doesn’t mean sauerkraut is spoiled.
Unfortunately, the odor caused by sulfur can be rather noxious, similar to dirty socks, rotten eggs, or goats. So even if it’s still practically consumable, the smell of sauerkraut might be too repulsing to have a bite.
However, if sauerkraut smells moldy or rotten, then it’s definitely spoiled. In that case, you should throw it away, as eating it can get you sick.
One thing you might notice happening with unpasteurized sauerkraut is that it appears to be bubbling. This is caused by the build up of gases caused by fermentation.
But because the lid is tightly sealed, the gases can’t get out. Luckily, you can easily solve this by opening the lid twice a day to get rid of air pressure. Bubbling usually happens within the first few weeks of fermentation and will diminish over time.
Aside from the smell, you might also notice some changes in texture and color. If you don’t keep the entire content submerged in brine, sauerkraut will dry out over time. It will also turn brown as a result of oxidation.
If you don’t add more brine to the packaging, sauerkraut will grow mold in a matter of days.
Once that happens, it’s time to dispose of it.
How To Store Sauerkraut?

An unopened jar of pasteurized sauerkraut can sit for a very long time when stored in your pantry or a dark kitchen cabinet away from the stove.
The unpasteurized version, on the other hand, stays fresh for longer when stored in the fridge. That’s because low temperatures inside the refrigerator slow down the fermentation process. As a result, sauerkraut doesn’t change in flavor and odor that fast.
Once opened, pasteurized sauerkraut should also be stored in the fridge. And not just that. You also need to make sure the container is properly sealed so that no air or moisture gets in.
Plus, since sauerkraut has such a strong odor, you don’t want the rest of the fridge to smell the same way, do you?
What’s more, it’s important to keep the entire content submerged in brine at all times. If not, sauerkraut will lose its crunchiness, which is part of the reason why we all love it so much.
If there’s not enough brine in the jar to submerge all the cabbage leaves, you can make your own.
For every ½ of a tablespoon of unrefined sea salt add a cup of filtered water. That will be more than enough to keep sauerkraut fresh in the fridge.
You might be tempted to grab a few bites straight from the container. But if the fork has already touched your mouth or other foods, you shouldn’t use it to take another scoop of sauerkraut.
By doing that, you can introduce potential harmful bacteria that will turn the content bad within just a few days.
Freezing is also an excellent way to extend the shelf life of sauerkraut. At such a low temperature, no microorganisms can grow, so there’s no way it can spoil.
With that being said, the freezer also kills good bacteria. So once you defrost it, it won’t stay fresh for more than a few days.
You can expect sauerkraut to change a bit in texture as well as taste once thawed. That’s partly because there are no more living cultures in it. But also because the it diluted a bit from melted ice.
Keep in mind that you should never freeze sauerkraut in a glass jar or container. Since sauerkraut will expand once frozen, glass packaging will burst under pressure, making a mess inside your freezer.
Instead, it’s best to transfer the sauerkraut to a plastic bag or container.
If you only need small portions of sauerkraut for your meals, you can also freeze it using an ice cube tray. To do this, scoop sauerkraut and fill the tray with it. Place it in the freezer until it’s frozen.
After the cubes turn solid, transfer the content inside a releasable bag or a container. Since they were frozen before transferring, the cubes won’t stick one to another, and you can take out only as much as you need at a time.
It’s important to transfer the cubes into a bag or a container to keep them away from air exposure. Otherwise, they’ll oxidize and turn brown at a much faster pace in your freezer.
To thaw it, keep the sauerkraut in the fridge overnight. It takes a long time to defrost, so you should plan it in advance.
If you’re short on time, thawing at room temperature might be tempting. But refrain from doing so, as harmful bacteria can grow during the long defrosting process. Instead, you can heat it in the microwave.
Alternatively, if you plan on using it for cooking purposes, you can put it frozen in the pan, where it will thaw rather fast.
Conclusion
If you’re a big fan of sauerkraut, there’s nothing wrong with stocking up on jars of your favorite product. Unopened, sauerkraut can last a pretty long time.
But once you open the packaging, that period drastically changes for pasteurized version.
To make the best use of it, you should go through the entire jar within a week or so from opening. Unpasteurized sauerkraut, on the other hand, can last for many months in your fridge.
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