Post #G23: An aside on lacto-fermentation and pickles

Posted on August 22, 2020

This is a second of two pickle posts.  The prior post was about the energy cost of canning pickles.  This post is about making pickles via lacto-fermentation.

If you want to try making pickles with the least possible effort, lacto-fermentation is the way to go.  It’s a lot easier than making a traditional vinegar (canned) pickle.

Among other things, it’s a quick way to take a temporary excess of cucumbers and keep them from spoiling.  For a while (like, a couple of months).  But if you want to preserve them for more than (say) a couple of months, without refrigeration, you’re going to have to can your finished lacto-fermented pickles anyway.

Lacto-fermentation of vegetables is so trendy you’ll have no problem finding instructions for it on the internet.  So think if this as a simple beginner’s guide, a  brief tour of how I go about it.  And a jaundiced view of the trendier aspects of this trend.

In a nutshell.

Source:  Perdue University Extension Service.

Everything you really need to know about making pickled vegetables is contained in the USDA guidelines, Section 6 (.pdf).




To lacto-ferment any vegetable other than cabbage, make up an acidic brine.  For one gallon of brine, that’s:

  • 1 cup salt
  • 1/2 cup vinegar
  • 1 gallon water

For smaller amounts of brine, refer to this table:

Anything but cabbage:  Put your vegetables in the brine.  If you’re pickling cucumbers, cut the blossom end off first.  Let it sit for a while (days to weeks).  Then eat it.

Cabbage:  Shred the cabbage.  Add salt (a scant three tablespoons per 5 lbs cabbage).  Mash it up a bit, so that it weeps and so makes its own brine.  Let it sit for a while (weeks).  Then eat it.

For both:  Weight them down or wedge them in place to make sure they stay fully submerged under the brine.  Cover the container with something, taking care to be sure that gasses generated during fermentation can escape.

The rest is just details.

1: How I ferment vegetables.

This section provides detail on how I go about lacto-fermentation of cucumbers and cabbage.

If you don’t follow the approach outlined below, take a look at the next section, where I describe the easiest way to start fermenting vegetables.  Just use whatever food-safe container you have handy, and use a food-grade plastic bag full of brine as the lid for your ferment.  That’s what I used to do, and it works just fine.

Half-gallon mason jars

After trying a variety of methods over the years, I do my lacto-fermentation in half-gallon canning jars/mason jars/Ball jars.  I find them ideal for lacto-fermentation, for the following reasons.

  1. You can buy a range of “air lock” devices ready-made to fit Ball jars.  The use of a proper airlock results in a much more sanitary ferment, with far less problem with (e.g. ) surface mold.
  2. They are easily sanitized in the dishwasher.
  3. The “shoulder” of the jar is ideal for keeping the vegetables under the brine.
  4. You can buy weights ready-made for Ball jars, again to keep the vegetables under the brine.
  5. You can see the fermentation proceed, and easily keep an eye on your progress.
  6. They’ll fit in your fridge door, so when the ferment is done, you can just put a plastic lid on them and pop them in the fridge until you’re ready to eat them.
  7. They are cheap, about $12 for 6 of them at any local store.

In fact, I’d say that the sole drawback to using half-gallon canning jars is that you can’t can in them.  You cannot use those to do canning (other than for some juices), per the USDA guidelines.  So if you end up canning your lacto-fermented pickles or sauerkraut, you’ll need to transfer them to quarts or pints before canning.

In the past, I’d do the fermentation in whatever — crock, glass container — and use a water-filled plastic bag as the “lid” to the container of fermenting vegetables.  (See next section).  Aside from avoiding contact between food and plastic, the use of half-gallon Ball jars is just vastly superior.  No spills, little or no surface mold, consistently clean ferments, fridge-door friendly, and so on.  It’s just vastly less hassle and more consistent to use Ball jars.

You can try this in quarts, but my experience is that that’s a little more hit-or-miss due to the lower volume of fermentable materials.  A half-gallon seems to be about the minimum volume that gets the right bacterial community going and gives a consistently good ferment.

Weights and measures for one half-gallon jar.  My recollection is as follows:  About five pounds of cabbage with three tablespoons of salt will fill a half-gallon mason jar with sauerkraut.  That’s with the losses of the outer leaves and cores and a bit lost when shredding.  Maybe a bit more, maybe a bit less, but not by much.  It’s fine if the kraut does not completely full the jar to the shoulder.  (That also matches the USDA guide which states 25 lbs of cabbage for 9 quarts of sauerkraut).  For pickles, I do it by volume.  More-or-less, a half-gallon volume of pickles, sitting loosely, will fill a half-gallon mason jar, packed tightly.  Per the USDA guide, that works out to about two pounds of pickling cucumbers per half-gallon container.  Every half-gallon mason jar of pickles requires a quart of brine.  I.e., when all the dust settles, every half-gallon mason jar of pickles is half cucumbers, half brine, and contains about 2 lbs of cucumbers.

Slaw board and how to use it — sauerkraut instructions.

You can cut up your cabbage by hand, but a slaw board makes it vastly easier.  It also gives you a consistent thickness to the slices, which gives you a consistent ferment time for all of your cabbage, and so on.  I think this was the smallest one I could find on some years back.  Cost $26.  Made in Poland — not something you see in your everyday kitchen appliance, but I guess they know a thing or two about sauerkraut in Eastern Europe.

If you already own a mandoline cutter, you can certainly substitute that.  Near as I can tell, the only advantage of a slaw board is that the multiple knives make it faster.  I’ve never used the slicing disk of a food processor for this, but there’s no reason not to.  You’ll have to chop the head of cabbage into smaller chunks, and empty it frequently.  But it should work.

Anything you can use to make coleslaw, you can use to make sauerkraut.  But a proper slaw board is arguably the best and fastest tool for the job..

Here’s the key to shredding cabbage with a slaw board:  Do it in the sink.  The process of shredding a few heads of cabbage sends little cabbage shreds everywhere.  Your first goal is containment.  Then you can think about food.  If you do this on the counter top, you’ll have cabbage shreds on the counter, on the floor, on your clothes — pretty much everywhere.

Detailed instructions:

  1. Set up your salt.  By the time you reach for the salt, your hands will be covered in cabbage shreds.  Figure out how much salt you need ( 3 Tbsp per 5 lbs cabbage), pour it in a dish, set it aside.
  2. Set up the shredder.  Take the largest stock pot you have, put it in the sink, put your slaw board on top and sit the back edge of your slaw board firmly against the back of the sink.  (So that, when you run the cabbage across it, moving the cabbage toward the back of the sink, the back of the sink keeps the slaw board from moving.  Much easier than trying to hang onto the slaw board by hand.)
  3. Core the cabbage.  Take your cabbage, remove any loose leaves, cut it in half, and generously cut out the core.  Don’t stint.  Use two deep angled knife cuts, one on either side of the core.  Keep the core and some large leaves. You’ll want a large core piece to keep the kraut below the brine (below), and any bits of core left in will produce unwanted tough bits in your sauerkraut.
  4. Quarter the cabbage if need be, to fit it on your slaw board.
  5. Grab one end of your slaw board, and run the cabbage down it from cabbage top to cabbage bottom.  If you run it through the other way — trying to cut the stem end first — it’s vastly harder.  The cabbage head tends to get stuck.  No clue why.  Basically, you take the top of the cabbage, and push it toward the back of the sink.
  6. Do I need to say that this thing has sharp blades, so act accordingly?  Yeah, I probably need to say that.  I used to wear cut-proof gloves, and that’s not a bad idea.  But I find that if I just keep one outer leaf intact, I can shred most of the cabbage with zero risk to my hands.  I end up with my palm flat on that leaf, and the slaw board won’t cut the leaf when it’s flat.  One way or the other, just be aware that this will cut you if you run your hand over the blades.  Duh.
  7. All shredded?  Now toss in the salt, and mix it like you mean it.  Use both hands.  Move it around.  Clench handfulls of it to break up the shreds and generally get things weeping.  Punch it down occasionally.  Just go to town.
  8. Stop when it gets good and wet.  After a minute or two, you’ll notice a profound change.  The cabbage takes up far less volume, and liquid is beginning to accumulate in the bottom of the pot.  You really can’t overdo the mixing, but you may stop any time after this has occurred.
  9. Put the first mason jar in the pot of shredded cabbage and pack it.  Toss the cabbage in by the handful.  (You do it this way because anything that doesn’t go in the jar just falls back into the pot, see?)  As you fill it, stop occasionally and use (e.g.) a wooden spoon to pack the cabbage in as tightly as you canStop just before you get to the shoulder of the jar.  Ideally, the liquid will come to or above the surface of the cabbage.  If not, you can add a little brine later.  Repeat as needed for however many jars you need to fill.
  10. First cleanup.  Clean up the area, your hands, the slaw board, the sink, the countertops, the stock pot you used, and so on.  But mostly, get the jars as clean as you can, in the sense of having no cabbage shreds above the liquid level.  Temporarily put a lid on the jar and wash the outside.  I find that a thin spatula helps on the inside.  Just get all the shreds off the outside, and off the inside above the liquid.  If you miss one or two, it doesn’t much matter.
  11. Weight or wedge the sauerkraut down.  Take one of the large leaves you saved earlier, cut a circle out of it slightly larger than the jar diameter, and work this into the jar, to cover up the top surface of the sauerkraut.  This keeps the “floaters” under the liquid.  If you have a glass weight, drop that in on top of that leaf, press it down so that liquid covers most of that cabbage leaf, and you’re done.  If you don’t have a glass weight, take the cabbage cores you saved earlier, and wedge them in place on top of the leaf, using the shoulder of the jar to keep them in place.  There are advantages to either approach.  The glass weight is cleaner and will not attract mold.  The core wedges keep the kraut in place better as it tries to expand (see The Ferment below).
  12. Cap it.  Put a lid on it.  You can get by with just putting a plastic storage lid on loosely.  (It has to be loose to let the gasses produced during fermentation escape.)  But I prefer to use some sort of airlock with a standard Ball jar band screwed in place.  Pictured at the top of this blog are what I’m currently using, Pickle Pipes (of which, here’s a cheap knockoff).  I used to use a different air lock, but these work and are convenient.
  13. Second, third, fourth cleanups.  Put your finished sauerkraut in some convenient place.  In theory, a cool place, but not too cool.  In practice, mine does just fine on the kitchen countertop, in an air-conditioned house.  Then wipe down all the cabbage shreds you find on the countertops.  Then put away a few items.  Then discover more cabbage shreds in unexpected places.  Iterate until no more cabbage shreds appear.
  14. Kraut management 1:  The ferment.  As it ferments, the kraut traps gas bubbles and expands.  You may have to open these up after a few days and press the gas bubbles out of the kraut, just to keep everything in the jar.  The higher you filled the jar, the more you’ll need to do that.
  15. Kraut management 2:  The holding period.  When it stops producing gas bubbles, it’s more-or-less done.  For me, at air-conditioned room temperature, that seems take the better part of two weeks.  You can eat it at any time.  I find that I can leave mine on the countertop for at least a couple of weeks after that.  But you should check periodically for mold forming at the top of the kraut.  That’s natural, it won’t kill you, but it will add off flavors.  If you see it, remove it.  Better yet, just put a storage lid on the jar (loosely!), and put it in the fridge.  Mine keeps several months at least.  I think I’ve stretched that to nearly a year, but by the end it was picking up off notes and was only good for cooking with.

Safety note:  If it doesn’t look good, or it doesn’t smell good, then throw it out and try again.  I can’t recall the last time I had a batch of sauerkraut go bad.  But it can happen.

An optional tip, for the spectacularly cheap thrifty reader.  You’re going to end up with a fair bit of discarded cabbage, starting with the large outer leaves.  Not the best part of the cabbage, but still edible.  Rather than toss that, put that aside in a bowl, and cook it when you’re done.  Some people even eat the cabbage cores, but that’s where I draw the line.

Pickle packing.

Briefly:  Cut a thin slice off the blossom end of your clean pickling cucumbers.  (Otherwise, enzymes in that end will give you mushy pickles).  Don’t skimp.  I take about a quarter inch off the end — about like a standard pickle chip.  Pack them as tightly as you can in the half-gallon jar, without crushing them outright.  It is far easier to set the jar on its side when packing half-gallon jars.  Toss in some dill or other spices as you pack.  When you get to the top, wedge some in from side to side, under the jar shoulder, to keep all the pickles in place as they fermentFill the jar with acidified brine per the USDA recipe and table above, so that cucumbers are well under the brine surface.  Ideally, add a glass weight.  Cap as above.

These are done when they stop bubbling and the brine clears.  At air-conditioned room temperature, mine usually take a little over a week.  Maintenance is as with sauerkraut:  If you don’t refrigerate them, check them periodically for surface mold and remove any that forms.  You’ve got a few weeks, once done, before you have to do anything with them, as long as you keep an eye on them.  The longer they sit, the softer they’ll get.  At least, that’s my experience.

A tip on the glass weight.  You don’t really need it, but if you do it just right, the bottom of the weight will be in the brine, but the top will not.  And you are left with just a narrow ring of brine exposed to the air.  That minimizes the likelihood of having mold grow on the top of the ferment.

But what if you don’t know your blossom end from a hole in the ground?  It’s the end that doesn’t have a stem on it.  It’s almost always lighter-colored, and usually slightly smaller, than the stem end.  The stem end is almost always a deep, dark green.  It’s the end that’s pointing down, in this picture.  Source:, Dave’s Garden Seeds.

If it’s still not clear, cut a slice off both ends.

Dos and don’ts, mostly don’ts.  You can’t used store-bought cucumbers that have been waxed.  You really can’t use full-sized cucumbers, at least not in half-gallon jars, mostly because I find that if I slice up the cucumber, it gets too soft during the fermentation.  You can’t use Pickle Crisp (calcium chloride) to firm up these pickles — that only works on canned vinegar pickles.  You can throw in neutral-tasting leaves with high tannic acid content (grape leaves, cherry tree leaves) to try to achieve a firmer pickle.  You can ferment at lower temperature, or ferment less completely before refrigerating, to try to achieve a firmer pickle.

Safety note:  If it doesn’t look good, or it doesn’t smell good, then throw it out and try again.  As with the kraut above.

That’s about it.

You can can either the sauerkraut or the pickles per the USDA guide cited above.  Or eat them raw.

2:  A zero-investment approach, or, how I used to ferment vegetables.

In a nutshell:  With this approach, you use a plastic bag filled with salt water (brine) as both the lid of your fermenting container, and the weight to keep the vegetables submerged.  As shown in this illustration from the USDA guidelines, Section 6 (.pdf).  (Towel optional.)

The only tricky part is getting that water-filled plastic bag to perch securely on top of your vegetables, without spilling.  And you will definitely want to put your container on a plate or tray to catch anything that spills out during the fermentation.

I do my best to make it sound like rocket science, below.  But it really us just as simple as that:  Plop a brine-filled baggie on top, and let it ferment.


Let’s say you just want to try fermenting vegetables, just to see if you like it.  You don’t have to do what I described in the body of the post above.  You can start with items that almost everyone will have in their kitchen.  No investment needed.

You’ll need table salt, ordinary vinegar, a container, and a plastic bag.  And a knife.  The container and the bag have to be “food safe”, and can’t be made of materials that react with acid.

The container: Size.  Larger is better, because that reduces the risk of a bad (spoiled) ferment.  My rule-of-thumb is a half-gallon or larger.  But there’s nothing wrong with fermenting in a quart jar.  I’ve done that.  You just have a slightly higher risk of a bad (spoiled) ferment.

The container: Material  Ordinary glass is ideal.  A used food jar is perfect.  (For years, I fermented in used gallon pickle jars).  You can use any plastic container that was sold to be used with wet food.  (For example, if you have nothing else, you could, in theory, cut the top off a two-liter soda bottle and use the bottle.)  You can use any stainless-steel container sold to be used with food, such as a stainless steel cooking pot.  As a last resort, you can use any container, as long as you line it with a food-safe plastic bag.

The container:  Shape.  The container needs a mouth wide enough to get the vegetables in and out.  Think “pickle jar” and you can’t go wrong.  You can use a crock — that is, a straight-sided container – as long it’s at least as tall as it is broad.

The bag:  Must be a food-storage bag, or some other bag sold to be used with food (such as a crock-pot liner or turkey-cooking bag).  To use the most-recognized brand name, you need a Baggie ™.  That’s what I mean by “food storage bag”.

The bag needs to be big enough that one or two of them, when partly filled with water, can spread out and cover the opening of your container.  It’s better if it’s an old-fashion bag that closes with a twist-tie, not a Zip-Lock bag, because those are easier to “perch” on your vegetables.  But, with care, you can use a Zip-Lock.

Don’t use: 

  • Don’t use anything designed to be decorative (such as a vase).
  • Don’t use any plastic not sold for food packaging (such as a bucket).
  • Don’t use a broad, shallow container such as a bowl (because that has too much surface area per unit of (fermenting vegetable) volume.)
  • Don’t use trash bags, shopping bags, or any other sort of bag that was not sold for food storage.

Everything else about fermenting vegetables remains as described in the main body of this post.  Acidic brine, cut a slice off the blossom end of your cucumbers, and so on.  But note that if you’re making sauerkraut, you can skip the slaw board, and cut up your cabbage by hand. The kraut won’t be quite as elegant, but it will work fine.

Then, fill whatever container you are using, but not completely full.  See how much space they left, in the illustration above?  Shoot for something like that.  Have enough liquid to cover all of your vegetables.  But leave enough space to perch a water-filled plastic bag, securely, on top of the vegetables. If you fill it too full, you won’t be able to get a plastic bag to sit securely on top.

Place your container on a plate or tray to catch overflow at the next step.  And leave it on that plate or tray as it ferments, again to catch overflow.

Fill your plastic bag part way with brine.  Use the leftovers from acidic brine you are using to ferment with. Or make up a little brine of that same strength, using the table of measurements near the top of this posting.  (The only reason for using brine, by the way, is that if the bag leaks, it won’t dilute the brine your vegetables are in.)

What do I mean by part-way?  Well … that depends.  It depends on your bag, and your container.  Take a look at the illustration above.  See how little water is that bag, compared to the size of the bag?  That’s what you’re shooting for.  You want the bag to be as slack as possible — so not very much water.  But you do need enough water to spread the bag flat, and to weight down the vegetables.

I suggest you take a bag, fill it with tap water, seal it, and try setting it on a plate.  Just to get the hang of it.  Too much water, and the the bag rolls over and spills.  Too little water and the bag won’t spread out.  Just right, and the bag sits there, reasonably stable, and reasonably flat.

And how big a bag? Again, that depends.  It needs to cover the entire liquid surface of your ferment.  Or, if you don’t have a big enough bag, two bags need to cover the that.

Test-fit the bag while you are still in the kitchen.  Put your container in the sink, put a brine-filled bag on top of the vegetables, and see how it looks.  Likely, some brine from the vegetables will overflow at this point.  You might have to take some brine out of the bag to get a good fit.  You might decide you need two bags to cover the entire surface of the ferment comfortably.  Fuss with it until you have a nice, secure covering over the entire top surface of the vegetables.

Place your fermenting container on a plate or tray, and move it to wherever you are going to leave it. 

Caution:  If the container is really full, or the bag looks unstable, take the bag off first, then move the container.  Put the bag on a clean plate, move everything, then replace the bag.   The point being that you can’t spill a lot of brine out of the container at this point, or you won’t have brine covering all your vegetables.  So if the liquid level is right up to the brim, you either need to take care not to lose any over the side, or you need to have a little extra brine around, to “top it up” when you get the container wherever it needs to be.

If all has gone well, there will be so little of the surface of the ferment exposed to air that you won’t grow any surface mold around the edges.  But you should check every few days anyway, and if you see visible mold around the edge of the bag, scoop it off.  In theory, you might have to top up the brine in the ferment, due to evaporation, but I’ve never had that happen.

Everything else — how to tell when it’s done, how long it can stand unrefrigerated — is the same as the instructions in the main body of the posting.


Commentary 1:  Lacto-fermented pickles versus vinegar pickles.

Source:  Amazon.

Common grocery-store shelf pickles are vinegar pickles.  They are preserved in vinegar, to acidify them enough so that they can be canned.  These all pretty much taste the same, plus or minus whatever spices were added.  That is, they taste like acetic acid (vinegar), which is what makes them sour.  You can certainly make your own vinegar pickles, or picked vegetables of many types, that way.

By contrast, lacto-fermented vegetables produce their own acid bath through the action of bacteria.  Various strains of bacteria consume part of your vegetables, and in the process produce lactic acid, along with many other compounds that (for better or worse) add to the flavor.  In the end (if all goes well), one harmless bacterium dominates:  Lactobacillus.  This is the same bacterium that you might find in (e.g.) yogurt.  These will taste sour due to the lactic acid.  But they’ll also have many other flavor notes as a result of the bacterial fermentation process.

Think of it this way.  Vinegar pickles are like vodka.  It gets its kick from a purified chemical, and not much else, unless you flavor it.  But you always know what you’re going to get.  Lacto-fermented pickles are like home-brewed beer.  It has the same kick to it, but it has an inherently complex taste.  And you’re never quite sure exactly what you’re going to get.

The other big difference is that lacto-fermented vegetables are (contain?) probiotics.  In theory, the (harmless) lactobacillus takes up places in your digestive tract that other (potentially less benign) bacteria would otherwise occupy.  Whether or not you believe that probiotics are helpful, compared to some little pill you might take, you get a huge dose of lactobacillus when you eat a dish of fermented sauerkraut.  Of course, if you can or cook with the pickles or kraut, you lose that as you kill off the lactobacillus.

Commentary 2:  Choice of vegetables

IMHO, your realistic choices for lacto-fermentation are shown graphically above.  My point is, there’s a reason that “pickles” means pickled cucumber, and that you can buy sauerkraut in any grocery store.  That reason being that, historically, they tasted pretty good when they were preserved via lacto-fermentation.

You will have people tell you that “you can lacto-ferment almost any vegetable”.  Technically, that’s true.  And in my experience — with rare exception — anything else ends up anywhere from the “well, that’s different” category to the outright spit-it-back-out category.

So if you’re new at this, I suggest you stick to the traditional two.  If you stray to something exotic, bear in mind two things.  This will soften up any vegetable you ferment, so start with something pretty substantial or you’ll end up with puree.  And in my experience, the bacteria pretty much leave the sugars alone.  So if you do (e.g.) carrots, you’ll get something that you can eat, but it’s definitely an acquired taste.  That I never managed to acquire.

Anyway, you’ve been warned.

Conversely, let me heartily recommend purple cabbage sauerkraut.  You’ve never seen a prettier pickled vegetable when it]s first put in the jar, and it keeps its crispness far better than green cabbage sauerkraut.

Finally, use a traditional head-type cabbage for sauerkraut.  Other types of cabbage can be fermented (e.g., Napa cabbage for kimchi) using different methods, but in my experience the traditional method of sauerkraut making doesn’t work for them.

Commentary 3:  Salt and water and vinegar.

Salt?  Regular table salt works fine, but kosher salt or canning salt will give your pickled vegetables a better appearance, for two reasons.  First, iodized table salt will react with sulfur compound in garlic and turn it blue-green.  You can still eat it, it just looks ugly enough that you won’t want to.  Second, anti-caking ingredients in table salt can remain suspended in your brine, giving it a slightly cloudy appearance, even after the fermentation has finished.

Water?  Regular tap water works fine.  Or, at least, it does for me. And I note that the experts — USDA Guidelines cited above — make no reference to any problem with using ordinary chlorinated tap water for for fermenting vegetables.  There’s no harm in using water that has been filtered or purified in some way.  But in my experience, that’s not necessary.

Most tap water in the U.S. is treated with chloramines.  Not chlorine.  Chlorine is old-fashioned, but very easy to remove from water.  (Just let it stand a while, open to the air.)  Chloramines, by contrast, are what most public water supplies now use, and are difficult to remove from water.  (Practically speaking, for human consumption, you can only do that with a big activated-charcoal filter).

I’m stating all this in order to contradict advice you might read, to the effect that  tap water will prevent your vegetables from fermenting.  Or prevent them from fermenting properly.  Or something.  That’s not my experience, nor does the USDA mention it.

My guess is, people who believe that you can’t use tap water seriously underestimate just how tough bacteria are.  Or, possibly, they live in a place with particularly toxic or noxious tap water.  If you can drink your tap water, straight up, I’d be surprised if you couldn’t ferment vegetables with it.

Vinegar?  Just don’t get fancy.  Vinegar is a chemical, not a condiment, when canning.  You use it to achieve a known level of acidity.  You can use any vinegar that says it has been standardized to be a 5% solution of acetic acid in water.  Regular, off-the-shelf distilled white vinegar is ideal.  As far as I have been able to determine, distilled white vinegar has an indefinite shelf life.  So says the Vinegar Institute.