What Happens if Water Kefir Ferments Too Long?

Today we will take a look at What Happens if Water Kefir Ferments Too Long? Now that you have read all the books and watched all the tutorials, you’ve fed your grains and started your first batch of water kefir. But uh-oh, life got in the way and now it has fermented a little longer than recommended. What now?

Water kefir grains piled on to a dark grain wood table with a wicker spoon of grains, a sprig of mint leaves, and a small jar of water kefir.

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Water Kefir, if left to ferment too long, has a much lower sugar content and becomes very acidic. This causes the water kefir to be more vinegar like and less appealing in taste. Over fermenting can also strain the kefir grains, reducing the beneficial bacteria and weakening the culture.


Water Kefir grains in sugar water in a clear jar beside a package for water kefir grains from Cultures For Health.

Water Kefir Grains

Allowing your water kefir grains to rehydrate for more than 4 days will starve the grains. Too long without fresh “food” can kill your water kefir grains.

If left to ferment too long, the water kefir grains will need to be fed with fresh sugar water. Switch out the sugar water every 24 hours for the next few times until grains start to return to normal.

If they have fermented longer than 6 days, the ability to rescue the grains is greatly reduced.

After the First Ferment

So maybe you are brand new to making this delightfully fizzy drink called kefir. You followed all of the directions. But your not quite sure how to tell if it is fermenting properly. Below I have a few things for you to look for to make sure your water kefir is on the right track.

  • The water will be somewhat hazy. Not clear, not opaque. Right in the middle.
  • The kefir water’s color should lighten up from the beginning to the end of your first ferment.
  • Your kefir will have a slight sweetness to it. Not syrupy sweet though.

Pro tip: Fruit Makes Fizz!

Add organic dried fruit, such as figs, dates, or raisins (free from additives like oils and sulfur) to your kefir grains. Not only will the grains get a boost of sugar and nutrients, but your kefir soda will have more fizz also.

Best thing about using this pro tip above? The raisins will also tell you when the sugar water is properly fermented by floating their way to the top of the jar.

I know what you are thinking. But Christen, I am trying to get away from sugar!! Why am I adding so much into this drink and calling it healthy!?

Such a valid question. The thing is though, the kefir grains need that sugar for the fermentation process. That is their fuel! The beneficial bacteria love it, and only leave a trace behind. Enough to make water kefir soda yummy.

Final Thoughts on Water Kefir Fermenting

When starting something new, there are so many questions and so many what ifs!

But mostly we want to know that we are following each step correctly and safely.

I hope this was helpful in answering a few questions you may have as you start to make your own water kefir at home.

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