Airlock or open fermenter?

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Airlock or open fermenter?

Postby Nsfermenter on Fri May 12, 2017 2:34 pm

Hi all,
I am new to fermenting and just made my first small test batch of sauerkraut.
I explained in detail in the introduce yourself thread, oops, should have done that in here, sorry bout that.

Basically, I just bought one of those large glass container with the rubber seal glass clamp down top type (like the old fashioned canning jars) and used that as a fermenter with just cheesecloth and a rubber band to seal it.

I used one medium green cabbage, and 1.5tablespoons of himylayan sea salt, nothing else.

I put a few leaves of cabbage on the top of the kraut and a small jar with a weight in it to weigh it down.

After about 2.5 weeks it was to my liking, tasted very close to the expensive health food store sauerkraut, nice and crunchy and pretty vinigary.

The only problem was the small patches of black and white fuzzy mold that was growing on the leaves on the top, so following the advice here, I just picked off the fuzzy leaves and threw them away.

It's now in the fridge, and no more mold has grown since.

I'm still alive after eating the kraut, so I'm assuming it's ok:)

So, the questions I have are fist about washing the cabbage, I always wash my veggies well, but i never see anyone wash their cabbage first, why not?
I'm not just concerned about contaminants but also pesticides because it's not organic. I know you can't get all the pesticides off, but every bit helps.

The other question is about airlocks as opposed to open fermenter.
If I used a sealed top with an airlock, would this solve the mold issue?

What happens if the veggies are not weighed down and protrude above the brine, but you have an airlocked container, would it go bad?

I'm pretty much an expert at brewing beer, but never made kraut until now, so I'm wondering how similar the processes are, I'm big on sanitizing everything well when making beer.

Thanks for your advice!
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Re: Airlock or open fermenter?

Postby Nsfermenter on Sat May 13, 2017 1:14 pm

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Re: Airlock or open fermenter?

Postby Christopher Weeks on Mon May 15, 2017 8:02 am

I rinse all my produce. I use organic when I can, but don't sweat it when that isn't an option. I rinse it all, but don't scrub or anything. It all seems to ferment.

Fermenting under an airlock might have eliminated your mold problem, but only if you never opened it. I think it's safe to say that the best course is to keep your produce under brine. That said, I have fermented many batches of veggies in Fido jars at this point where the produce poked up out of any brine, and while the stuff up top might not be good, mold never grew. Not once. Until I opened the jar the first time. At different stages in the fermentation, the microbes are kicking out different amounts of gasses. Early on, they flood the environment with CO2 that pushes most of the O2 out through the lock. So mold can't grow. But if you open it at four weeks to taste and then seal it back up, the fermentation has slowed way down and CO2 is only being produced slowly. If there are mold spores, they might enjoy the new atmosphere before any CO2 builds up and prevents them from thriving.

Also note, the stuff that sticks out of the brine acquires a kind of yucky texture. So I don't have any experience with it being harmful, but I do sometimes scrape it off and throw it out. Keeping your stuff under brine is a generally good practice.
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Re: Airlock or open fermenter?

Postby Nsfermenter on Thu May 18, 2017 6:57 pm

That's great info, thanks!!
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Re: Airlock or open fermenter?

Postby bacteriaguy on Mon May 29, 2017 12:44 pm

Yes, that's true about not opening it once you put air lock on it. It undoes all the good you were trying to accomplish by using an air lock because it allows oxygen and mold spores to rush in every time you open it. And to make maters worse, after the first week of fermentation, the production of CO2 slows down, so even after you close it back down, the oxygen you let in doesn't get pushed back out very quickly and gives the mold spores you let in plenty of oxygen to start growing. I use an air lock lid and a fermentation weight to keep all the vegetables fully submerged.
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Re: Airlock or open fermenter?

Postby JohnDulleck on Mon May 29, 2017 4:59 pm

I keep my kraut submerged during fermentation, in a Fido jar with no lock. After the first week, I open the jar about twice per week to check for floaters, and never see mold growing on the surface of the brine. It is only if there is a floater that I might see mold, and even then, since I remove floaters, I see mold only very occasionally.
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Re: Airlock or open fermenter?

Postby patobrocks on Thu Aug 13, 2020 3:53 pm

I am fortunate that I learned of the Fido jars early in my fermentation efforts. I use nothing but a standard Fido jar for my anaerobic ferments. I can't hardly remember not having sauerkraut in a Fido. I have traveled cross country and even lived in my car for months at a time with jars of sauerkraut.

I have gotten sloppier and more careless as I've grown older. I had one 3L Fido jar full of sauerkraut that was lost and forgotten once. It was over 18 months old, and when I tried it the fermented cabbage was still crunchy. It was a little more sour than what I preferred, but used it mostly as a condiment.

I usually open the jar after a week or two just to taste it and critically observe. I also make fermented oatmeal in mason jars. I ferment it for three or four days, and then nuke it. My recipe has evolved over the years to just putting a half of cup of old-fashioned cheap oatmeal in the jar with twice as much filtered water and a large dollop of kraut. I usually use my oldest jar of kraut (now it is 60 days old), so the Fido jar is opened almost daily.

I have never had any problems at all while using the Fidos for kraut, kvass, garlic, beans, and something else I am sure but can't remember now.

Oh, if I were not blaspheming before, I will share with you all my kraut recipe. I do not mess with whole cabbages anymore. Since I am old, I simply buy shredded cabbage made for coleslaw. I use 2 teaspoons of Real Salt per pound, patiently wait, pound a little while in the jar. I pound until the cabbage is submerged and fill only to just below the neck of the jar and seal it up. The cabbage may spring up so it looks like all the cabbage is above the brine, but this is not a problem. Not a problem for the good old trusty and reliable Fido. If I am going to open the jar early, I am patient. When I seal the the jar, I put some masking tape with the date at the level of the cabbage. I wait for the cabbage to raise up at least an inch before opening, I always open it while not distracted, because I want to notice the pop and the pressure on the lid.

If the lid's pop seems weak, I use some pliers to bend the metal band where it catches on the catch. Of course, I am always observing. throughout the life of the kraut, if the pop when releasing the lid gets too weak, and it is losing the ability to take a proper adjustment, I will change the lid to one with a newer metal band.

Oh, I must realize that presidents come and presidents go, but fermentation is forever. And I believe that ferments have made me pandemic proof.
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Re: Airlock or open fermenter?

Postby baerdric on Sun Oct 11, 2020 1:28 pm

I don't wash my cabbage.

But I do carefully take off the outer leaves. The inner leaves are untouched by human hands, topical sprays, animal excrement, etc. Yet it does seem to carry the lactobacteria needed for good fermentation.

Personally, I use this for all my vegetable sources. I simply do not buy food that cannot be either completely cleaned or peeled down to an untouched layer. For instance, although I know the nutrition differences, I don't use romaine or other leaf lettuce, I use head lettuce. I supplement nutrition in my salads with homegrown sprouts and/or sauerkraut.

I've worked in the fields, I know that many workers rarely use the port-o-let. I'm OK without the risk of e.coli.
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