How Long Is Sauerkraut Good Once It's Been Opened?

Sauerkraut is one of those love-it-or-hate-it foods. Although there is a time and place for it, not everyone takes to its sour notes and borderline rotten fragrance. But if you pair it with some rich pierogies and kielbasa, or add a few spoonfuls of it to your New York-style hot dog, its flavor suddenly makes a lot more sense. And, the good news is that unsealed sauerkraut actually lasts a long time in the refrigerator; it should stay fresh for four to six months once opened.

Sauerkraut is just fermented cabbage. The cabbage is usually massaged along with a generous amount of salt, which helps it to release water. Then, it's placed in a jar (for approximately one week to one month) where it will ferment, thanks to the natural bacteria that grow in this environment. Those bacteria are also what makes sauerkraut — and similar foods like kimchi – smell funny. But in this case, that funky smell isn't a bad sign; it's a sign of sauerkraut's preservation method and its resulting long shelf life. Still, it's important to properly store sauerkraut to get the most from its shelf life. It's even more important to know how to tell when it's past its prime.

A jar of opened, homemade sauerkraut can last as long as six months. But if you've purchased the store-bought kind, you should follow whatever the manufacturer suggests in terms of how long it will last once it's been opened. You can store opened sauerkraut on the counter, but it won't last as long that way. It will only last about a month before it starts to dry out.

To help your opened sauerkraut last as long as possible, store it in an airtight container in the fridge. Whenever you use it, make sure you scoop it with a clean utensil to introduce as little additional bacteria into the cabbage as possible. 

Start checking your sauerkraut for signs of spoilage after about four months just to be safe. Check for smell and appearance. If the sauerkraut begins to smell stronger than it should, or give off a rotting odor, it's no longer good to eat. Also, sauerkraut should keep its lighter color; if its color has changed, it's too old and should be thrown away. And, of course, you should check for any fuzz, which is a sign of mold.