Quick Visual Guide to Vegetable Fermentation Questions

Reader Contribution by Kirsten K. Shockey
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End of summer and preserving go together like peanut butter and jelly, coffee and cream, Tom and Jerry or Fred and Wilma — at least for those of us who crave the deep satisfaction that comes with putting things up. Our soul is calmed with every new jar added to the larder — we will eat well. Winter: Bring it on. (Yes, we also are the ones who tend to sleep better when the woodshed is full.) Of course, that is generalizing as these days there are many folks in cities who are preserving the bounty from the farmers market.

In the toolkit of preservation is the ancient art of vegetable fermentation that is ideal for low-acid veggies, which cannot be canned. As ancient as fermentation is, it is also brand new for many, as it has been metaphorically waiting in the back of the closet to be rediscovered. A lot of questions arise with this revival. The loudest question seems to be:“Is it safe?”

This is a reasonable question when you consider that fermentation is a live process and with that comes many variations of normal. In light of the season, I wanted to come up with a quick visual guide to common fermentation sights — I don’t want to call it “troubleshooting” because often these things that look wrong can, in fact, be fine. 

Your mother always told you beware of a dented lid — well, in fermentation it is okay. There has been a lot of active fermentation in this batch of pickles and the lid was tightened so the building carbon dioxide couldn’t escape. Just open the lid (which may be difficult due to pressure) and let out the excess gas. In some cases, this will cause the brine to bubble over. See the next picture.

This active frothing ferment is just alive and effervescent. Carefully press down so that the vegetables are back under the brine that is left. This was fermented using a simple burp method while on a camping trip. It got a little warm but was perfectly delicious on campfire hot dogs.


This cloudy brine with floating and settled white sediment is normal. Don’t be concerned — enjoy instead!

A little bit of mold can sometimes form on top of any ferment. Where there is exposure to oxygen things can grow — just remove. Remember everything anaerobic and under the brine is fine. The following photo shows also shows a layer exposed to oxygen.

Kahm yeast and other “scummy” yeasts have moved into the top layer of the ferment where there was oxygen. Remove this whole top layer. All of the ferment under this layer is good.

Top view of the yeasts on the layer of ferment exposed to the air. Just remove until you get to a layer of brine.

When Things are Really Wrong

Didn’t see what you are looking for? Visit Help! Troubleshooting Fermented Vegetables and look through the fun fermentation images posted there, or even join the discussion by submitting your own.

And what if? Yes, what if your ferment is bad? It happens, not often, but it does. It is good to remember that you will absolutely know that if your ferment is bad there won’t be any question. You won’t wonder when it “smells funny” if that is just how it is suppose to smell or not. If it is bad, you will know—all of your senses will guide you to not put it in your mouth. It will smell more than funny; it will smell so awful you won’t even need to get your nose near it.  You won’t want to spend time searching for answers—you will know oxygen got in and had a little too much fun. The bad ferment will smell like rot, or like a warm compost pile with too many food scraps—which is right where it should go!

Kirsten K. Shockey is a post-modern homesteader who lives in the mountains of Southern Oregon. She writes about sauerkraut and life — but not necessarily in that order. She’s written a complete book ofFermented Vegetables and maintains the websiteFermentista’s Kitchen.

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