Lacto-Fermentation Guide: How to Ferment Vegetables (+ Recipe Ideas) (2024)

Have you ever wondered how lacto-fermentation works? I’ve got you covered! This in-depth guide will walk you through how to ferment vegetables so you can make your own deliciously-flavored veggies at home.

Fermented veggies make a great snack on their own, but they also elevate the flavor of other dishes.

In this post, I’ve included a basic fermented vegetables recipe, plus some additional inspiration with different flavor profiles and veggies – like carrots, string beans, cauliflower, radishes, etc.

What is lacto-fermentation?

Let’s start with the basics of lacto-fermentation!

All veggies have lactic acid bacteria on (or in) them. Lactic acid bacteria is “good” bacteria (a.k.a. bacteria that helps diversify and support your gut microbiome, rather than making you sick).

Ultimately, the goal with lacto-fermentation is to create an environment where lactic acid bacteria thrives, and harmful bacteria dies.

Thankfully, lactic acid bacteria thrive in salty and acidic environments, whereas other bacteria can’t handle the salt or low pH.

So, with lacto-fermentation, we want to create a balance with brine (salty water) that’s salty enough to kill other bacteria, but not too salty to kill the lactic acid bacteria, too.

That way, lactic acid bacteria will thrive, veggies will ferment, you’ll get a nice “good” bacteria boost (probiotics! <- more on those in that blog post), and you won’t cultivate “bad” bacteria.

Generally, that salty-enough-but-not-too-salty environment comes out to about 5% salt for brined veggies (which are what I focused on for this post).

So, breaking it down into two main steps:

1. The veggies go into a salty environment, which weeds out “bad” bacteria that can’t handle salt. Bacteria that naturally occurs on the veggies can start to digest sugars in the veggies, producing an acidic environment and CO2 (hence the slight bubbles you might see).
2. The now salty andacidic environment weeds out more “bad” bacteria that can’t handle a low pH. Since lactic acid bacteria thrives in a salty, acidic environment, it takes over and continues to digest sugars and create more acid. That’s why the more time you allow something toferment, the more acidic and less sweet it will be. (Think about super-funky kombucha vs. sweet kombucha, aged wines, etc. It’s a slightly different organism doing the fermentation, but a similar concept.)

Lacto-Fermentation Methods

When fermenting veggies, you have two options.

The first (the ‘brining method‘) is to make a brine with water and salt and submerge the veggies in it.

The second (the ‘dry-salting method‘) involves salting the veggies and letting the salt bring out all the juices to create a brine, then submerge the veggies in their own salty juices.

The brining method works best for veggies that don’t give off a lot of moisture, like sliced carrots and radishes, cauliflower, green beans, cucumber spears, etc.

The dry salting method works best for super watery veggies, like cabbage, or shredded carrots/radishes/cucumbers, etc.

Shredding the veggies like carrots, radishes, and cucumbers gives them a lot more surface area to let out juices, hence the dry salting method is best for those. But when you just use carrot sticks or cucumber spears, they don’t tend to let out as much liquid, so brining works best.

It’s certainly not a hard-and-fast rule, and fermentation is meant to be fairly flexible. On that note – sliced peppers and onions will usually work well with either method.

Mason Jar Fermentation: How it Works

Fermented Vegetable Recipe Ingredients & Steps

Here are the general ingredients you’ll need (see the recipe card at the end of the post for the full details/measurements):

• Veggies (green beans, carrot sticks, broccoli or cauliflower florets, sliced peppers, sliced beets, etc.)
• Salt (kosher salt or sea salt)
• Seasonings of choice (red pepper flakes, cumin seeds, peppercorns, whole garlic cloves, herb sprigs, etc)
• Equipment: clean glass jars
• Optional: fermentationweights/springs, valved or airlock lids

Start by placing your veggies and seasonings into jars (again, see the recipe card at the end of the post for combination inspiration).

Be sure to leave at least 1 inch of space on top of the veggies. (Rule of thumb: it’s usually better to use too large of a container vs. too small!)

Next, use a kitchen scale (if possible) to measure out 5 grams of salt to every 100 grams of water that you’re using. (This is the base for your 5% salt brine).

I recommend weighing the salt and water rather than using volume, because salt weight:volume ratios vary drastically between different types of salts.

But if you don’t have a scale and still want to ferment, using approximates should usually work. In general, 1 teaspoon of kosher salt is about 5 grams and 1 teaspoon of fine sea salt is about 6 grams.

Mix together salt with room-temperature water, stirring vigorously, until salt is dissolved.

Then, pour the brine over the veggies until they’re submerged. Leave about 1/2 inch space in the jar above the brine. If necessary, use a weight or spring to weigh the veggies down so they stay fully submerged (links to some products to try are below in the “equipment” section).

Use a valved or airlock lid to cover. This allows built-up gas to escape without letting excess air or bugs inside the jar.

If using a regular lid, don’t screw it on completely tight (and be sure to open the jar once a day to release built-up gas).

Keep jars at room temperature for 3-6 days.

At the 3-day mark, taste the veggies to see if they’ve reached the acidity level/pickled taste that you like. If they’re salty but without any tang, let sit another day and test again each subsequent day until they’re to your liking.

Once they are fermented to your liking, enjoy, and store them in the fridge for up to 3 months.

Pickling vs. Lacto-Fermenting

The main difference between pickling and fermenting is the presence of probiotics (“good” bacteria) with fermentation.

Fermentation uses natural bacteria from the vegetables to achieve the desired flavor, whereas pickling uses an acidic substance (often vinegar) instead. With fermenting, you get that flavor from a natural chemical reaction.

Lacto-Fermentation Equipment

If you’re planning on fermenting with any frequency, I would recommend investing in the weights/springs/valved or airlock lids.

They just make the whole process easier, and they’re not too pricey as far as kitchen equipment goes.

The top two fears most people have around fermenting are growing mold and having jars explode.

These items help to eliminate those accidents by releasing pressure without letting additional oxygen in and keeping veggies fully submerged.

Here are affiliate links to the tools I’d recommend: airlock lids,weights,springs & valve lids.

The Best Veggies to Ferment (+ Recipe Ideas)

And now, here’s some recipe inspiration for different veggies and flavor-enhancing herbs/spices!

• carrot sticks+ 1 clove garlic+ pinch of black peppercorns+ 1 sprig fresh dill
• cauliflower+ 2 cloves garlic+ pinch of red pepper flakes+ pinch of black peppercorns
• green beans+ 2 sprigs fresh dill+ 2 cloves garlic+ pinch of black peppercorns
• sliced radish, jalapeno, onion, and carrots+ pinch of cumin seeds+ pinch of red pepper flakes+ 1 clove garlic
• sliced peeled beets+ 1 clove garlic+ pinch of black peppercorns
• watermelon rind is awesome for fermenting – like cucumber, but less prone to getting mushy. Try this recipe: Fermented Watermelon Rind

I hope you found this helpful – now it’s time to get fermenting! 🙂

You’ll find the full vegetable lacto-fermentation recipe (plus more notes on troubleshooting, etc.) at the bottom of this post. Enjoy!

Looking for more posts on related topics and/or preparing fruits and vegetables? Check these out:

• Fermented Watermelon Rind
• Health Benefits of Fermented Foods (a guest post from a fellow RD a few years ago)
• What are Prebiotics and Probiotics?
• Pickled Watermelon Rind (Two Ways)
• How to Peel a Pomegranate (+ Seed It)
• How to Roast Frozen Vegetables (+ Recipe Ideas!)
• The Best Frozen Vegetables to Buy
• How to Love Veggies
• How to Can Your Own Food at Home (this post is from back when I doing my nutrition internship at a local public health organization – my co-intern and I taught a class on canning!)

Have you tried fermenting before, or do you plan to? Let me know in the comments!