How Long Does Sauerkraut Last?

How Long Does Sauerkraut Last?

We all want our refrigerated food to be safe to eat. That’s why we go through the fridge on a regular basis and follow the rule, “When in doubt, toss it out.” But unlike most foods we keep in the fridge, our wildbrine probiotic fermented foods come ready-colonized by health-giving bacteria. So, what’s the story with these foods? How long does sauerkraut or kimchi last, once the jar is opened?

How Long Does Sauerkraut Last?

Here’s some good news: sauerkraut and kimchi can last in the fridge for a month or two past the expiration date that’s printed on the package—If you understand what’s going on and what keeps these foods safe and tasty.

Your wildbrine sauerkraut or kimchi is fermented rather than salt cured. That means the vegetables were kept submerged in a weak brine solution of between 2 to 5 percent salt, depending on which vegetables were fermented. At first, the vegetables carried into the fermentation vessel any microorganisms that were on their surfaces, including spoilage organisms as well as beneficial Lactobacillus acidophilus and other acid-loving bacteria (often referred to as LAB—lactic acid bacteria).

During fermentation, the LABs went to work on the sugars and carbohydrates in the vegetables, turning them into lactic acid. As the weak brine became more and more acidic, the spoilage organisms were killed off. The vegetables developed the lip-smacking sour flavors that make ferments so delicious. After all, the word “sauerkraut” is German for “sour herb.” By the end of the initial fermentation, the LABs rendered the vegetables tastier, more nutritious, perfectly safe to eat, and probiotic, meaning the bacteria that fermented the vegetables could now take up residence in your digestive system and continue to provide health benefits and improved nutrition as they participate in your gut microbiome.

Incidentally, salt curing is done with a stronger brine—from 10 to 20 percent salt or more. That amount of salt will preserve the vegetables, but is too salty to allow the LABs to grow, so salt-cured foods are not fermented.

So, what’s this mean for our question: how long does sauerkraut or kimchi last once the jar is opened? And the answer is a couple of months or even more if three requirements are met.

celebrate sauerkraut

First, the vegetables must remain submerged a 1/2 inch or so beneath the brine in the jar. If they float to the top and are exposed to air, they will eventually become moldy and inedible and the jar will be spoiled. If there’s not enough brine in the jar to cover the vegetables, add a little filtered water, enough to fill to above the vegetables. To keep the vegetables submerged, weigh them down with a small plate, cup, or freezer baggy filled with weak brine.

Second, the sauerkraut and kimchi must be kept refrigerated at all times. If you want to serve some with a meal, transfer the meal’s worth to a cup or bowl and put the jar of kraut or kimchi back in the fridge without letting it sit out and warm up.

Third, only use a clean utensil to take the fermented vegetables from the jar. Don’t eat from the jar by reinserting the utensil in the food. If you double dip, you’ll be seeding the food with a wide range of mouth and other bacteria, and it will eventually spoil.

Over its time in the fridge, sauerkraut and kimchi will become more acidic as the LABs proliferate, the crunchiness of a fresh jar’s vegetables may abate and become softer over time. But as long as you keep the vegetables submerged and enjoy the flavors, you’re good to go.

About the Author: Sonoma County resident Jeff Cox is the author of 24 books, including The Essential Book of Fermentation (Avery, 2013)



We just discovered your WildBrine Sauerkraut and love it!
A concern I had though was that I couldn’t find any information on the container about how long the sauerkraut lasts once the jar had been opened. I did find it on your website with the three rules for keeping it fresh.
It would be very helpful if that information was printed on your container.
Thank you for a healthy, delicious and convenient food!

The wild Bunch

Hi Karen – Thanks so much for the love! If only we had more room on the label to put all the info that customers would like to see! We try to include as much helpful information as possible on our website though. Glad you found what you needed.


Regarding the salt brine I can make to add to what’s already in the jar of sauerkraut, I’m wondering if a course salt (that I normally grind) will work without grinding it. It’s called Selina Celtic Sea Salt. I also have a Himalayan Cooking Salt, Ava Jane’s Colima Sea Salt, and Redmond Real Salt, which is mined. Thank you, Shari

The wild Bunch

Thanks for the question Shari! We suggest adding a little water to the kraut if you need the liquid to get to the level of the solids.


Awesome article! Thanks!
By the way, if I eat all the kimchi out of the jar, can I then put more vegetables into the jar and re-pickle them?
Also, what books would you recommend on making kimchi or fermentation in general?

The wild Bunch

Hi Billy – This is not recommended for these reasons: 1) Probiotics tire and die off after a while. Using the brine means using micro-organisms that are on the down slope of their lives. Start with fresh vegetables every time to get fresh, vibrant organisms; 2) Carrying over a “starter” from one batch to another risks not being able to control/sort good (or better) batches from each other; in the food business this is definitely a food safety no-no as there is no control/trace-ability between batches; and 3) the complex flavor of fermented foods comes from the fermentation progressing from more neutral pHs (i.e. acidity) to lower PH’s (higher acidity). As the ferment goes down this path, different organisms are more prevalent at the various pH’s. All of those organisms contribute different flavor notes. So to get a symphony of flavor in the end product, always start with fresh produce and let the ferment progress at its own pace. The right pace is set by providing the right environment (65-70F temp), the right amount of salt for kimchis & sauerkraut (~2% by weight), and an anaerobic environment via “weighing down” the solids.

On books on fermentation – refer to Sandor Katz’s books, although I would insert a little more science in some recipes to be safe: 1) always ferment using salt since no salt fermenting is not as safe; and 2) always ferment to a pH below 3.7.

– Chris Glab, Co-Founder of wildbrine


I have an unopened jar of recently purchased sauerkraut.
Fridge died, but kraut got moved to neighbours fridge while still fairly chilled.
Got fridge fixed and brought kraut back.
Fridge died overnight and nothing was cool come morning :/
The jar is still sealed, and it didnt get hot exactly, but would a jar of seals sauerkraut still be safe to eat if say it was at room temp for 4-6 hours?

The wild Bunch

Hi Sally – Sounds like that fridge is doing you no favors! If the kraut was only out of refrigeration for 4-6 hours, then it should be fine to eat. But the added heat might have restarted a bit of second fermentation, which can change its texture and flavor a bit. But this short of time likely didn’t affect it. Hope this helps!


How long can you keep the sauerkraut juice/brine for use in salad dressing? Thanks

The wild Bunch

Hi Barb – Not quite sure since we’ve never been asked this before. But it should probably be good for about a month or so if kept in the refrigerator.

Ed S.

There is no expiration date on the container of sauerkraut that I bought from Costco.
Or I just can’t find it.
How long will the sauerkraut last if I don’t open the container?

The wild Bunch

Hi Ed – The sell-buy date is printed on the lid but sometimes the printing isn’t super easy to read. But as for how long it stays fresh unopened, it is the same as if it were opened – about a month or two after the sell-by date.


One of the comments says the 4-6 hours out of the fridge unopened is okay. My mother purchased a jar for me yesterday and didn’t realize it was perishable before giving it to me today. I’m probably closer to 20 hours, unopened, unrefrigerated. Too much?

The wild Bunch

Hi Sami – The kraut should be fine. We usually advise people that if it’s under 24 hours out of refrigeration, that it should still be okay to eat.


Love the Wildbrine Organic Sauerkraut!! Never had it before, saw it at Costco, and tried it. We opened it on Memorial Day to have with our Brats, and as a “side”. Have a bit left over, it’s been refrigerated ever since. Plan to have it on 4th of July. Still good? tastes fine, but I am the only one who eats it.

The wild Bunch

Hi Connie – Welcome to Team wildbrine and thank you for your kind words! Yes, the kraut is still good, as long as it has been refrigerated and covered with brine. This is a blog post telling you more: Thank you for reaching out.