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tutorial Why Your Ferment Grew Mold, What to Do,and How to Prevent It

If you’ve been fermenting vegetables for a while then you’ve probably faced a shock discovery. You’ve cut or shredded your vegetables, added salt or brine, submerged them in said brine, and then left them to ferment.
Then a day or more later you opened your jar to find, much to your horror, a white film of mold. Or, worse yet, a big hairy mold patch of varying colors.
You’re probably heartbroken, or at least disappointed. You may assume that all of that time and money you put into those vegetables you were fermenting was wasted.

Recognizing Mold
The first thing to know is that the white film that is often present in vegetable ferments is probably not mold, but something called kahm yeast.
Kahm yeast is a type of film that can readily be found in cultured and fermented foods. It is not harmful, although it may be unattractive or even smell a little odd. It should be removed from the ferment so it doesn’t impart a bad odor, but a little bit left in the jar won’t hurt the vegetables, and won’t hurt you.
Kahm yeast is likely to develop if a fermentation solution is insufficiently acid, especially when you start it, or if there is not enough salt in the brine. Kahm can also develop if the culturing temperature is too warm, or if the brew is over-exposed to oxygen. Poor hygiene can be another cause.
If kahm yeast develops in your ferment, skim it off the surface of the liquid. Discard any solid matter that has it. As usual, your senses are the test: if it smells and tastes okay, it probably is.
True molds are usually colorful and the deposits are round and often fuzzy or fluffy. They might even be white, but there is a distinctive difference between the smooth film that is kahm, and the puffy growth that is mold.

What to Do with a Moldy Ferment
If you opened your jar or vessel up to find a layer of mold on top, don’t panic. You may be able to easily dispose of this and have perfectly good fermented vegetables below the brine.
Lacto-fermentation is an anaerobic process meaning it must be in an oxygen-free environment for it to happen properly and fully. Any oxygen put into the mix can cause unwelcome microorganisms such as mold or yeasts.
So while your vegetables may be happily fermenting under the brine, the surface of the brine is still exposed to oxygen if you are using a jar or open-crock method of fermentation. This is common, though, and it was very common in times past to simply go to the cellar to check on the ferments, scrape any growth off the surface, and retrieve the fermented vegetables below.

Factors That May Contribute to Mold Growth
If you are experiencing a mold epidemic of sorts in your ferments then their maybe something more at play. You may want to investigate the following possibilities:

Fermentation Temperature
Ferments like sourdough and yogurt might prefer a warmer temperature of 80°F or 110°F, respectively, but vegetable ferments, in general, prefer a cooler temperature. This makes it especially difficult when you are attempting to preserve at the peak of the growing season, which is most likely the hottest time of the year.
Try to find a cool place to ferment your vegetables. A root cellar is ideal, and traditional, but a cool basement or garage is also helpful. Or just find the coolest place in your home. A temperature of 65° to 80°F is your best bet in avoiding mold.

Vegetable Submersion
Probably the most important factor in lactic acid fermentation is the submersion of the vegetables underneath the brine. Lacto-fermentation is an anaerobic process, meaning it requires a no-oxygen environment.
If you are experiencing mold problems check to make sure your ferment is under the brine. If it is not then you will need to weight the vegetables down with a clean rock or weight.

Salt Content
The purpose of salt in a lacto-ferment is to inhibit the growth of undesirable pathogens including molds and other microorganisms. Too much salt won’t allow lactic acid fermentation to occur fully, but too little salt can result in off flavors or mushy vegetables.
Likewise, too little salt will not preserve the food between the start of fermentation and when the lactic acid bacteria begin to proliferate and create an acidic environment on their own. This can lead to mold more readily taking hold of your ferment.

Introduction of Starter Culture
The introduction of an already established starter culture can help prevent unwelcome pathogens from taking hold of your ferment before the lactic acid bacteria have a chance to form.
You can use whey or a starter culture in these circumstances for a little extra insurance.

Bad Microorganisms Present on Your Vegetables
Finally, consider the vegetables themselves. Are they in a state of decay? Did you wait too long to get them fermented? Were they sprayed with chemicals that could interfere with the natural fermentation process?
If any of these are a factor then you may want to consider using only fresh, organic produce in your ferments if you have access to them.
In conclusion, mold occurring above the brine is a fairly normal part of fermentation, but anything out of the ordinary may be caused by a number of non-ideal situations for your ferments.
 
Source: http://www.culturesforhealth.com/vegetable-ferments-mold
 
I thought you might appreciate this one RM.
I'd wager that you've responded hundreds of times to questions pertaining to mold and kham yeast....not to mention optimum fermentation temp,and the importance of keeping the mash submerged beneath the surdface of the brine solution.
 
BTW...a belated housewarming package from Ky will be heading your way Monday...heavliy weighted toward the "warm" end of the scoville scale.
 
Chili Monsta said:
If you’ve been fermenting vegetables for a while then you’ve probably faced a shock discovery. You’ve cut or shredded your vegetables, added salt or brine, submerged them in said brine, and then left them to ferment.
Then a day or more later you opened your jar to find, much to your horror, a white film of mold. Or, worse yet, a big hairy mold patch of varying colors.
You’re probably heartbroken, or at least disappointed. You may assume that all of that time and money you put into those vegetables you were fermenting was wasted.
Recognizing Mold
The first thing to know is that the white film that is often present in vegetable ferments is probably not mold, but something called kahm yeast.
Kahm yeast is a type of film that can readily be found in cultured and fermented foods. It is not harmful, although it may be unattractive or even smell a little odd. It should be removed from the ferment so it doesn’t impart a bad odor, but a little bit left in the jar won’t hurt the vegetables, and won’t hurt you.
Kahm yeast is likely to develop if a fermentation solution is insufficiently acid, especially when you start it, or if there is not enough salt in the brine. Kahm can also develop if the culturing temperature is too warm, or if the brew is over-exposed to oxygen. Poor hygiene can be another cause.
If kahm yeast develops in your ferment, skim it off the surface of the liquid. Discard any solid matter that has it. As usual, your senses are the test: if it smells and tastes okay, it probably is.
True molds are usually colorful and the deposits are round and often fuzzy or fluffy. They might even be white, but there is a distinctive difference between the smooth film that is kahm, and the puffy growth that is mold.
What to Do with a Moldy Ferment
If you opened your jar or vessel up to find a layer of mold on top, don’t panic. You may be able to easily dispose of this and have perfectly good fermented vegetables below the brine.
Lacto-fermentation is an anaerobic process meaning it must be in an oxygen-free environment for it to happen properly and fully. Any oxygen put into the mix can cause unwelcome microorganisms such as mold or yeasts.
So while your vegetables may be happily fermenting under the brine, the surface of the brine is still exposed to oxygen if you are using a jar or open-crock method of fermentation. This is common, though, and it was very common in times past to simply go to the cellar to check on the ferments, scrape any growth off the surface, and retrieve the fermented vegetables below.
Factors That May Contribute to Mold Growth
If you are experiencing a mold epidemic of sorts in your ferments then their maybe something more at play. You may want to investigate the following possibilities:
Fermentation Temperature
Ferments like sourdough and yogurt might prefer a warmer temperature of 80°F or 110°F, respectively, but vegetable ferments, in general, prefer a cooler temperature. This makes it especially difficult when you are attempting to preserve at the peak of the growing season, which is most likely the hottest time of the year.
Try to find a cool place to ferment your vegetables. A root cellar is ideal, and traditional, but a cool basement or garage is also helpful. Or just find the coolest place in your home. A temperature of 65° to 80°F is your best bet in avoiding mold.
Vegetable Submersion
Probably the most important factor in lactic acid fermentation is the submersion of the vegetables underneath the brine. Lacto-fermentation is an anaerobic process, meaning it requires a no-oxygen environment.
If you are experiencing mold problems check to make sure your ferment is under the brine. If it is not then you will need to weight the vegetables down with a clean rock or weight.
Salt Content
The purpose of salt in a lacto-ferment is to inhibit the growth of undesirable pathogens including molds and other microorganisms. Too much salt won’t allow lactic acid fermentation to occur fully, but too little salt can result in off flavors or mushy vegetables.
Likewise, too little salt will not preserve the food between the start of fermentation and when the lactic acid bacteria begin to proliferate and create an acidic environment on their own. This can lead to mold more readily taking hold of your ferment.
Introduction of Starter Culture
The introduction of an already established starter culture can help prevent unwelcome pathogens from taking hold of your ferment before the lactic acid bacteria have a chance to form.
You can use whey or a starter culture in these circumstances for a little extra insurance.
Bad Microorganisms Present on Your Vegetables
Finally, consider the vegetables themselves. Are they in a state of decay? Did you wait too long to get them fermented? Were they sprayed with chemicals that could interfere with the natural fermentation process?
If any of these are a factor then you may want to consider using only fresh, organic produce in your ferments if you have access to them.
In conclusion, mold occurring above the brine is a fairly normal part of fermentation, but anything out of the ordinary may be caused by a number of non-ideal situations for your ferments.
 
Source: http://www.culturesforhealth.com/vegetable-ferments-mold
 
THANKS FOR THE TIME AND HELP !
 
 
I did a little scouring of old posts and came up with a couple of pictures of Kahm and Mold in ferments.
 
**** WARNING, the following is for Mature Stomach's Only! If your stomach is under 18 years of age or if it's the morning after the night before, we've all been there ;) please go forward to the next post :)
 
Kahm Yeast:
 
Kahm1_zps23d0a10a.jpg

 
Kahm2_zpsbea8214f.jpg

 
Kahm3_zps9bbf58cc.jpg

 
Mold:
 
Mold1_zps10e3e305.jpg

 
Mold2_zpsa9ebe61a.jpg
 
Chili Monsta said:
Excellent RM....!
Once again, a picture is worth a thousand words.
No doubt which is which.
 
You mentioned fresh peppers in your ferment.  So I shouldn't use peppers from the freezer that I have been saving up until I have enough to do one kind of pepper?
 
Amazingly enough....it takes monumental sub zero temps to kill the LAB bacteria...(but boiling kills them)...go forth and ferment with that stock from the freezer !!!
CM
 
Use a starter from a previous ferment and a little sugar source if needed and ferment whatever you want. Active lacto bacteria can live for ages in the fridge. Give it a little fresh fruit puree for the sugar and you will have many billions of them in a couple days.
 
Thanks for this info! When I checked my newest ferments this evening, I discovered one with mold on it. I did not have enough of weights, so I used the top of a Weck canning jar on this one, hoping it would be enough. It wasn't.
 
Ok, I need to address something that Ive seen in a few posts and around the web when people are talking about ferments that have gone astray. So heres my Public Service Anouncement.

If you have a ferment that gets ANYTHING other than a Kahm yeast in it, DO NOT, in any way think that its going to be a good idea to take just a little taste of it! Even a little taste from the bottom of the jar or just a spoon of the juice.

Botulism is nothing to toy around with. Its a poison, which can be cured, but yourre not going to have a very good time, just take a look at the symptoms listed by the CDC:

Botulism is a rare but serious illness caused by a toxin that attacks the bodys nerves.

Symptoms of botulism usually start with weakness of the muscles that control the eyes, face, mouth, and throat. This weakness may spread to the neck, arms, torso, and legs. Botulism also can weaken the muscles involved in breathing, which can lead to difficulty breathing and even death.

Furthermore:

The bacteria that make botulinum toxin are found naturally in many places, but its rare for them to make people sick. These bacteria make spores, which act like protective coatings. Spores help the bacteria survive in the environment, even in extreme conditions. The spores usually do not cause people to become sick, even when theyre eaten. But under certain conditions, these spores can grow and make one of the most lethal toxins known.

The conditions in which the spores can grow and make toxin are:
Low-oxygen or no oxygen (anaerobic) environment
Low acid
Low sugar
Low salt
A certain temperature range
A certain amount of water

For example, improperly home-canned, preserved, or fermented foods can provide the right conditions for spores to grow and make botulinum toxin. When people eat these foods, they can become seriously ill, or even die, if they dont get proper medical treatment quickly.

Did you see the part there that said, ONE OF THE MOST LETHAL TOXINS KNOWN?

To find out more you can visit the CDC site at: https://www.cdc.gov/botulism/general.html
 
Please....Read and heed....
 
                                                          Did you see the part there that said, ONE OF THE MOST LETHAL TOXINS KNOWN ???
 
 
When in doubt.....throw it out.
 
Excellent post RM !!
 
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