I get this question in various forms all the time. How long can fermented foods be left to ferment?

Did I ferment my sauerkraut too long? “Help! I went 10 days by mistake, but the recipe said 7 days! Is it bad?”

I’m not surprised I get this question all the time, because there is so much conflicting information out there. Some recipes will say to ferment sauerkraut for 3 days while some say 3 months. Same for fermented veggies.

Is there really a set fermentation time for fermenting vegetables? The short answer is no. It varies and depends on a few factors.

The number one factor that affects fermentation time

There are many variables that can affect the time it takes for your suaerkraut, pickles, fruit and even kombucha and water kefir to be ready. Fermentation time varies depending on the temperature of the room you’re fermenting in.

Temperature

Temperature affects the speed at which fermentation occurs. A cooler room will slow fermentation while a warmer room will speed it up. Ideally most ferments do best in an environment that’s at a comfortable room temperature, about 60 – 75 degrees fahrenheit.

Hot weather

During the summer the temperature of the kitchen rises. The heat speeds up the activity of the bacteria and can make a typical 5 day ferment be done in 3 days.

Cold weather

During the winter, if your kitchen is cold, a typical 5 day ferment could take as long as 7 or 10 days. Even two weeks. It’s safe to ferment for a long period of time.

Salt

The amount of salt you used in your sauerkraut or fermented vegetables will affect fermentation time. Too little salt will speed up fermentation, but may cause it to become slimy and develop mold. Too much salt can slow down fermentation significantly.

Learn My 3 Simple Steps to Get Perfectly Salted Sauerkraut Every Time here.

Personal Preference

Time can depend on taste preference. The flavor of pickled vegetables and sauerkraut will develop and get more complex over time. Textures can change too.

If you like your sauerkraut more crunchy, then ferment it for less time, if you like it more soft, let it go longer.

Pickled vegetables tend to be more crunchy the less they ferment too. But that also depends on the texture of the vegetables. Carrots hold their crunch very well, while radishes will get softer the longer you let them ferment.

Some people believe that the longer you let it ferment the more bacteria will be present. Some people let their sauerkraut ferment for at least 20 days in that case. Some people think the opposite is true.

What should you do?

Personally I let all my vegetables and sauerkraut ferment until the pickle brine is cloudy or the sauerkraut is bubbly and then I do a taste test. If it tastes sour and I like the consistency, I’ll put it in the refrigerator to eat. If I don’t think it’s sour enough, I will leave it out longer to ferment for a few more days and taste it again.

I think you should get comfortable with tasting your ferments too. You’re only going to eat it, if it tastes good to you.

Don’t worry if your ferment is taking longer than instructed, because time can vary significantly depending on these factors.

So, how long can fermented foods be left to ferment? As long as you want.

You can let your vegetables and sauerkraut ferment for several weeks, months or days. It depends on temperature, salt and your personal preference. Experiment with your own ferments and you’ll find a process you like best.

How long do you like to let your sauerkraut, pickles or other foods ferment and why? Let me know in the comments below.

Happy Fermenting!

-Danielle