My kitchen currently resembles the laboratory of a mad scientist.
There’s my sourdough starter bubbling away by the oven, a container of continuous brew kombucha doing it’s thing on the island, and a 2-gallon crock of sauerkraut fermenting away in the corner.
I’ve come a long way, considering I used to be scared of fermented foods. Both the sights and smells of fermenting foods turned me off for years, not to mention the worry it wouldn’t taste good. (I’m sorry, but there are some seriously unappetizing fermented food recipes floating around online…). All that to say, I avoided fermenting foods for a looong time.
Now that I’ve spent a few years making things like sauerkraut (a tasty classic), dilly beans, fermented pickles, kimchi, and even fermented ketchup, I’m not only gaining confidence with fermented foods, but I find myself actually craving them.
I’ve made plenty of ferments with my trusty glass mason jars and an airlock system, which are perfect for small batches of fermented goodness. However, I’ve always been drawn to fermenting crocks– not only for their decor appeal, but also because it’s a little more true to history if we’re taking into account how the old-time homesteaders fermented foods.
What is a fermenting crock?
As you can guess from the name, these crocks are simply jars (often ceramic or stoneware) that are used to hold veggies as they ferment. You’ve probably seen them at most antique stores, or perhaps being used in various aspects of farmhouse decor (they are definitely trendy these days), but most folks don’t realize they actually serve an important culinary purpose. If you’re curious about using crocks instead of mason jars for your ferments, here are a few things to keep in mind:
Benefits of Fermenting Crocks:
- They are long lasting – these things are so hefty and hardy that you can plan on giving it to your grandchild one day
- They’re perfect for large-scale bulk fermenting
- They are wasy to fill and scoop out of, versus a small-mouthed jar
- They are attractive. I really like the look of them on my kitchen counter, especially knowing the deliciousness brewing inside
- They’re also great at corralling other things, like kitchen utensils, when you’re not fermenting in them
Limitations of Fermenting Crocks:
- They are more expensive than a simple mason jar
- They are larger items that take up storage space in your home, unless you agree with me on the last point above, which of course then nixes this point. I always find great uses for them when they’re not holding fermenting veggies
- You’ll still need mason jars for storing the food after fermentation is complete
If you’re serious about fermentation, fermenting crocks are a great addition to your homestead kitchen (these are some other must-have items for a homestead kitchen).
Types of Fermenting Crocks
There are two main types of fermenting crocks: open crocks and water-sealed crocks.
Open Crocks
Open crocks are the traditional ones you stumble upon in antique shops or spot in grandma’s house. They’re old-fashioned (which suits me just fine) and super easy to use and clean. They don’t have any fancy parts. They’re literally just a large, open crock with no top. This is my 2-gallon open crock, which I love.
While you can certainly use grandma’s open crock or buy one at an antique store, check it over carefully for cracks or other issues. You want a non-cracked vessel for proper, safe fermenting.
The most common sizes for open crocks are 2-gallon, 3-gallon, or 5-gallon, so you can easily stuff whole vegetables inside for fermenting. After you fill the open crock with the produce of your choice, you put in a weight. I use an actual fermenting weight, but you can also use something more frugal from your kitchen, as long as it’s clean and heavy. The purpose of the weight is to keep the food under your brine. Then you cover the fermenting crock with a towel or cloth, or you can purchase a lid for your open crock (like this one).
Advantages of an Open Crock
- On average, they are less expensive than water-sealed crocks.
- You feel more old-timey and homesteady with these traditional crocks.
- The open, wide tops and straight walls make them easy to clean.
- You can fit large quantities of whole veggies in them.
Disadvantages of an Open Crock
- If you inherit an older crock, you’ll need to purchase or improvise a matching lid
- If you only using a towel or cloth as a “lid”, outside air can still enter the crock, which can result in surface mold or Kahm yeast. There’s nothing wrong with this harmless yeast, but you will want to skim it off.
- You need to either buy or make your own fermenting weights.
- It can be easier for flies and fruit flies to get into the crock if it’s only covered with a cloth.
- It’s easier to have failed ferments due to being such a simple device.
Water-Sealed Crocks
Water-sealed crocks have a lip to hold water and a lid that fits inside that lip and prevents outside air from entering the crock once you pour water into that lip and create a “seal.” But carbon dioxide, which is created during fermentation, can still escape. These crocks also come with weights that were made for that exact crock, so it makes the perfect barrier.
Water-sealed crocks didn’t used to be too easy to find. But as fermentation becomes a little more popular, you can find more water-sealed crock options (like this pretty blue-striped one).
Advantages of a Water-Sealed Crock
- The sealing of the vessel greatly reduces any chance of mold or Kahm yeast (a harmless yeast) from forming.
- The sealing also keeps fermentation odors inside the crock.
- Flies and fruit flies cannot get into your water-sealed crock.
- The thick sides and sealed top lead to a slightly more stable temperature inside the crock, compared to an open crock, which can help you with fermenting success.
Disadvantages of a Water-Sealed Crock
- Water-sealed crocks need more maintenance—you do need to refill the water occasionally or air will flow inside.
- The shape makes it more difficult to clean afterward.
- The shape also can makes it hard to pack the crock full of veggies.
- Water-sealed crocks are usually more expensive than open crocks.
Both types of crocks are truly great options for big batches of tasty fermented goodies in your home.
How to Use a Fermenting Crock
Once you’ve chosen a fermentation crock, it’s not hard to start using it! Here are the basic steps to using a fermenting crock:
1. Clean and soak the fermenting weights
Start with clean fermenting weights so you can avoid mold issues.
Fermenting weights are important because they keep the vegetables under the brine. If the veggies aren’t covered with the brine, they’ll get covered in mold (yuck). Presoaking your fermenting weights in water prevents them from soaking up your brine.
2. Wash your fermenting crock and produce
Obviously, you want to start your fermentation process with clean tools and produce. This greatly reduces your chance of spoilage. Wash your fermentation crock in hot soapy water.
Even if your veggies come from the garden, it’s a good idea to wash off any potential dirt and whatnot from them as well.
3. Prep your vegetables
You can ferment pretty much anything, and there are loads of awesome fermenting recipes out there. Whatever veggies you use, after you rinse them, you may want to ferment them whole (like pickles) or shred them or chop them. I have a whole segment in my Heritage Cooking Crash Course with all the nitty-gritty details if fermentation is something you are ready to add to your kitchen repertoire.
For a basic rundown, if I’m making sauerkraut, I’ll shred the cabbage either with a good kitchen knife or a food processor. I’ll sprinkle on about 1 tablespoon of sea salt per cabbage head. I like to use my hands to combine the cabbage and salt. You can also use a cool fermenting stomper like this one.
I squeeze the cabbage and salt together and it creates its own brine solution (if you’re making a different fermenting recipe, you might have to make the brine solution).
(Sometimes it takes a while for the cabbage to start releases its juices, as you can see in the photos.)
4. Stuff it into the fermenting crock
Whether you use an open-crock or a water-sealed crock, simply put the veggies and any possible spices into the fermenting crock. Use a fermenting weight to push the veggies down, and make sure to completely cover them with the brine.
5. Keep an eye on things
Put your fermentation crock somewhere where you can keep an eye on it. Your fermenting crock (especially if you use an open crock) might overflow if the liquid bubbles over due to the fermenting process. So you might want to put it in a shallow bowl or container to collect overflow. Also with an open crock, you might need to occasionally skim off any buildup of yeast or mold on the top.
If you use a water-sealed crock, you’ll have to watch the water levels and possibly refill it so that the seal stays effective.
6. Play the waiting game
The fermentation process will be done in about a week or two, but some people like super fermented foods, and you can wait even longer than that if you want. I like to do a taste test after 10 days to see if it’s the right amount of tang for my family. If it isn’t tangy enough, I’ll let it ferment for a few more days before taste testing again.
7. Store your fermented food
In the old days, homesteaders would keep their ferments in the crocks in their root cellar or cold storage area. However, since most of us don’t have root cellars (or unheated rooms in our home that won’t freeze) we have to make some adjustments. If the vegetables are left in the crock long-term, the fermentation process will continue, resulting in very tangy food after a while. This isn’t necessarily the end of the world, but your family may or may not appreciate super-sour sauerkraut, if you know what I mean.
Therefore, in order to stop the fermenting process, you will need to put your fermented food in the refrigerator once the initial fermentation period is over. The downside to using fermenting crocks, instead of simple mason jars, is that they are usually too big and heavy to stick in your fridge.
I usually scoop the fermented food out of the crock and into mason jars to store in the fridge. Most ferments will last at least 3 months in the fridge.
Fermenting Crock Q & A’s
How should I care for my fermenting crock?
After using it, wash your fermenting crock with mild soap and warm water and let it air dry. Avoid exposing it to extreme temps, and do not clean it in the dishwasher (if you could even fit it in there).
How should I store my fermenting equipment?
Don’t store the weights inside the fermenting crock. They might get moldy in there. Keep the weights stored separately in a dry place. Store your fermenting crock in a dry, temperature-stable place if possible. Unless you use it for everyday storage in the off season, then no storage required.
How big of a fermenting crock should I buy?
In general, if you’re fermenting 5 pounds of fresh veggies, you’ll need a 1-gallon crock. 10 pounds of veggies calls for a 2-gallon crock. Twenty-five pounds? You’ll need a 5-gallon crock.
What can I use for a fermenting weight if I don’t buy one?
If you’re using a household item, make sure that the material won’t corrode, get moldy, or expand when wet. Avoid wood, plastic, and metals. A kitchen plate works well.
Whatever kinda crock you use and whatever veggie you ferment, if you’re new to this, start small. And realize that it is an acquired taste. But our family quickly fell in love with the delicious tang of the gut-healthy food I ferment. I hope your family does too! Let me know what winds up to be their favorites!
Listen to the Old Fashioned On Purpose podcast episode #28 on this topic HERE.
The first time I used my lovely Humble House fermenting crock, I neglected to stay on top of the water around the lid (in my defense, I was birthing a baby!), and the stones became moldy. I’ve tried boiling them 10 mins, and it helped some, but there is still staining, and I am afraid to use again because they are porous. Any tips on how to thoroughly clean them, or are they a lost cause now?? I’m so sad because it was not a cheap tool. Would love your advice!
Hi Chariti! One thing you can try after you’ve scrubbed off the mold is placing your stones in a pot with hot (not boiling) water and a few tablespoons of vinegar. Then you can place them in the oven at a low temperature to dry them out or to make sure they’re thoroughly dry. I hope this helps!
I did what Kayla suggests when the same thing happened to mine, but wasn’t sure how to keep it from happening again. My solution was to put the weights inside of little ziplock sandwich bags, and it works pretty well. It keeps the moisture from getting into the rocks and making them moldy again, but it holds the stuff down in the crock. You can just rinse the outside of the bags off and re-use them if you don’t want to throw them away every time!
Oh, interesting idea! Thanks for coming back and sharing how it worked for you!
I just made my first batch of Sauerkraut !!!! I am so excited and I purchased a stoneware crock at a second hand store. Using a plate as a weight….. I hope I will be clucking away a week from now at my fermented food ?
Im new to all this. But determined
I ended up purchasing glass fermenting weights the same size as my original weights. It’s made it so much easier.
When you ferment anything doesnt it create alcohol before it creates any vinegar
Is it normal to smell your ferment in a water sealed crock? This is only the second time I’ve used it but I didn’t notice smelling it the first time with sauerkraut. This time I’m making kimchi, and ever once in awhile when I’m by it, I can smell it. I’m hoping it’s just the gas bubbling out the lid? ?
After several months of use my weights, too, formed an unremovable mould, which was more unsightly than dangerous but in the end I went for some of these glass weights.
https://www.amazon.com/Luna-Glass-Crock-Weights-6-5/dp/B016HKYDEK?th=1
Is there a maximum for “headspace”? I made my first batch of sauerkraut with my 2L Humble House water crock, but it was only about half full.
Do you use primary and secondary weights? By primary I mean a cabbage leaf or the like to keep all the small bits from winding their way around the secondary weights (ceramic) to the top of the brine.
I love that idea!
I listened to your podcast on fermenting foods. Great information! I also enjoy fermenting, but have a lot to learn yet.
Thought I should mention that it might be good to put a disclaimer that some older crocks you might come across might have a lead-based paint on them. They can be tested to be sure.
My pickle beans have been in th crock for 9 days, they are starting to smell and I’ve noticed what I think may be yeast or mold on the top will my beans still be good
If your porous ceramic crock weights have mold on them the best way to clean them is to place the dry weights in a cold self- cleaning oven and run a cleaning cycle. The 550 degree heat will kill anything living on or down inside the weights. Allow them to cool inside the oven then store them in a cool, dry, dust free place – not inside your crock!
We have a 25 gallon open crock. We have a hors-d voeuvre plate big enough to fit the inside with 1/4” space on edge all around. My question is can I use a heavy duty garbage bag on top of this filled with water as a weight and to seal it off so it can ferment ?
Is there a maximum for “headspace”? I made my first batch of sauerkraut with my 7L water crock, but it was only about half full. I bought a crock that is too large and sometimes just want it half full.
Hi, When I was making my first batch of kraut in my 3L SauerCrock, I was also way short, like 2/3 full. This was because when I weighed my cabbage, I weighed it whole, instead of after cored, lol. My crock says about 5lbs of cabbage. I read that this was not an ideal thing, so I bought another cabbage, processed it with the correct amount salt to make the 2% salinity and added it (the next day!). 6 pounds really pounded down was right to allow for the cabbage leaf and weights on top and a few inches of juice. Now I always buy more than I need and have leftover. Hope this helps although you probably figured it out by now! 🙂
Before I got my ceramic weight and lid I used gallon ziplock bags filled with salt water (2% salt per weight of water) as a weight and then used a big platter as my lid and it worked fine.
We have used 1 gallon Ziploc bags full of water to weigh down a plate and it has worked great. Still, we just broke down and bought a new water seal crock. Fixing to start a batch of Sauer Kraut this afternoon.
We usually make decent size batches and can the finished kraut. I know, we lose the health benefits of freshly fermented foods, but it sure is nice to have your own sauer kraut around for St. Patrick’s Day or any time you are hungry for a really good Reuben.
We’ve found that freezing sauerkraut (with brine) doesn’t cook it like canning, and it defrosts as crunchy as fresh. I don’t know if freezing kills the probiotics, but it does yield a better texture!
Is there a maximum for “headspace”? I made my first batch of sauerkraut with my 2L Humble House water crock, but it was only about half full.
I used my water sealed crock and it made a good batch of kraut. The puzzling thing is that it was always wet under the crock, and I finally put a dish towel under it. It got soaking wet after a few days. I had to add water to the cabbage every few days.,I can not find a crack of hole in the crock. What could be causing the water to gather at the bottom?
Hi, that is concerning! The top sides of the crock must have kept dry or that would have been obviously noticeable for you; like if the water reservoir was overflowing from bubbles. If you kept adding water instead of 2% brine, you were lucky your batch was successful, as you are reducing the salinity each time! (Make 2% to 2.25 % brine by WEIGHT of cabbage. This recipe here is very unreliable as cabbage can be anywhere from 3 to 6 lbs!) Did you do a test with a small amount of just water in the crock? Then I would contact the manufacturer even if your warranty is up. ; )
I too have a question about headspace. I am a beginner and received a 3 gal water crock as a gift. It is too large for our needs and before I purchase a smaller one, I am wondering if it is advisable to use it partially, meaning filling with as much veggies as I have, making sure they are covered and properly submerged, and using the water seal on top. Does this sound like a problem?
I’m pretty sure that as long as the veggies are properly submerged, you should be fine using a larger vessel.
I purchased a beautiful Ohio 1 gallon crock! I used it for the first time. I washed, rinsed, dipped in boiling water (boiled the weights for 10 minutes and air dried with the crock and lid. I am concerned and confused. I washed my organic cauliflower, zuchinni, carrots (peeled) and onions. Placed them in the crock with a Redmond Salt brine of 8 teaspoons of salt per quart of spring water (no bleach or flouride). Filled the crock with brine over the weights about 2 inches and about 2-3 inches head space. I placed it on the cool floor as it was running in the 90’s outside and went on vacation for about 8-9 days. I came back to a thick layer of fuzzy grey mold and the brine is pink. What went wrong?
It’s possible that the temperature wasn’t cool enough for ideal fermentation. I suggest reading this article for more: https://culturesforhealth.com/blogs/learn/natural-fermentation-vegetable-ferments-mold I hope that helps!
I have 2 open crocks that have lids. I just checked my sauerkraut and kimchi. They both have maggots in them. I thought the lid would keep flies and knats out. What did I do wrong? What can I do next time? This is the first time this has happened to me. This was my 3rd batch of each.
How sad! Perhaps the lid doesn’t fit too snug. Try using extra protection next time (but it needs to allow air inside), like clean cotton cloth or coffee filter secured tightly with a rubber band is enough to keep flies out. I hope you have a more successful ferment!
Thank you. I will find a cloth but will have to figure out a way to secure it down as my crocks are each 1 gallon. Maybe I will also put the lid over the top.
I was thinking of maybe using cheese cloth over the top? do you think that will work to keep bugs out?
I’m doing my first sauerkraut ferment in a 2 gal. Ohio Stoneworks water seal crock. I have it sitting on my kitchen counter and monitor the water in the moat daily. It has been four weeks since I “sealed” the crock and am planning on going to seven weeks before opening. This morning I found the water level in the moat was empty. I added more water to refill the moat and began wondering if the empty moat would have allowed air inside and ruin my ferment. We live in South Carolina, and we keep inside temperature around 70 degrees. Any thoughts on this would be greatly appreciated. Thank you
Thanks for this wonderful site! Question – can I use old bean crocks I don’t have and can’t afford one of these fermentation beauties. Thank you
Compare the materials used to make your old bean crock with the materials used for a fermenting crock. You can also use glass jars for fermenting if you cannot afford a fermenting crock. Jill has plenty of recipes on her blog where she uses glass mason jars. For example, check out her recipe here: https://www.theprairiehomestead.com/2015/08/fermented-pickle-recipe.html
Have you ever used a hogs bladder, (reproduction available) to seal a crock? I am looking to do so for a living history demonstration this coming spring.