How to Ferment Food at Home: A Beginner’s Guide to Lacto-Fermentation

Fermentation is the most recent food preservation method I’ve been obsessed with. At first, it seemed a little intimidating, but in reality I love to eat fermented food and found it easy and fun to make.

If you’ve ever eaten sauerkraut, kimchi, or a truly good dill pickle, you’ve eaten fermented food. But making it yourself can feel intimidating the first time: you’re leaving vegetables out on the counter for days and trusting that “good” bacteria will win out over “bad” bacteria. The good news: fermentation is one of the safest and most forgiving preservation methods there is, once you understand the handful of rules that make it work.

This guide is your starting point. It covers the science in plain language, the equipment you actually need (and what you don’t), the step-by-step process, food safety basics, and where to go next once you’re ready to try a specific recipe.

This article is part of my homestead cooking series where I share how to make from-scratch food instead of buying it at the grocery story.  From homemade bread and jelly to homemade condiments.  I'm Gretchen and I've been homesteading for over 15 years.  Here at the Backyard Farming Connection, I connect the lines between growing your own food, raising your own animals, and putting it all together in the kitchen.

What Is Fermentation, Really?

Fermentation is a natural preservation process where microorganisms, mostly a family of bacteria called Lactobacillus, convert the natural sugars in food into lactic acid. That acid is what gives fermented foods their signature tang, and it’s also what preserves them: the acidic, low-oxygen environment makes it very difficult for spoilage organisms and harmful bacteria to survive.

This specific process is called lacto-fermentation, and it’s the method behind sauerkraut, kimchi, fermented pickles, and countless other traditional foods found in cultures around the world. Unlike vinegar pickling, nothing acidic is added at the start — the food creates its own acid as it ferments. That’s also why fermented foods are alive with beneficial probiotic bacteria, while vinegar pickles are not.

My Favorite Fermentation Recipes

Why Homesteaders Ferment

Beyond preservation, there are a few reasons fermenting earns a permanent spot in a homestead kitchen:

• It uses what you already have. A cabbage surplus, a heavy carrot harvest, extra garden peppers: fermentation is often the best use for a glut of a single vegetable.
• No canner or special equipment required. You can start with a mason jar you already own.
• The flavor is genuinely different. Fermented foods have a complexity, funky, sour, alive, that vinegar-based pickling can’t replicate.
• Gut health benefits. Fermented vegetables are a natural source of probiotics.

Equipment: What You Need vs. What’s Nice to Have

To get started, you need:

• A clean glass jar (a wide-mouth quart mason jar is the standard starting point)
• Non-iodized salt (kosher, sea salt, or pickling salt — iodine and anti-caking agents in table salt can interfere with fermentation)
• Filtered or dechlorinated water, if your tap water is heavily chlorinated
• A way to keep vegetables submerged under the brine (more on this below)

Nice to have, once you’re hooked:

• Fermentation weights sized for wide-mouth jars, which hold vegetables under the brine far more reliably than a improvised solution
• Airlock lids, which let fermentation gases escape without letting outside air or contaminants in
• A ceramic fermentation crock for larger batches — this is a serious upgrade if fermenting becomes a regular part of your kitchen routine. I wrote more about when a crock is worth the investment in my homesteading tools roundup.

The Basic Process (This Works for Almost Any Vegetable Ferment)

The core method behind sauerkraut, kimchi, and most fermented vegetable ferments follows the same basic pattern:

1. Prep your vegetables. Wash, then chop, shred, or slice depending on the recipe.
2. Salt them. For dry-salted ferments (like sauerkraut), this is typically about 2% of the vegetable’s weight in salt. For brined ferments (like whole pickles), you’ll mix a saltwater brine instead, usually in the range of a 3–5% salinity.
3. Pack it tightly into a clean jar. Press down as you go to remove air pockets and encourage the vegetables to release their own liquid.
4. Submerge everything under the brine. This is the single most important step: see the food safety section below.
5. Cover loosely. Fermentation produces gas, so an airtight lid can cause pressure to build. Use an airlock lid, or a regular lid “burped” daily to release pressure.
6. Let it ferment at room temperature. Most vegetable ferments take anywhere from 3 days to a few weeks, depending on the recipe, your kitchen’s temperature, and how sour you like it. Taste along the way.
7. Move to the fridge once it’s fermented to your liking. Cold temperatures dramatically slow fermentation, so this is how you “pause” a ferment at the flavor you want.

Food Safety

Fermentation has an excellent safety record when a few basics are respected: this is not a nervous, hyper-technical process. But there is one rule that matters more than any other:

Keep your vegetables fully submerged under the brine at all times.

Anything exposed to air is at risk of developing mold or a harmless-but-unappetizing film called kahm yeast. As long as everything stays under the brine, the low-oxygen, acidic environment does its job and keeps spoilage organisms from taking hold. This is exactly what fermentation weights are designed to solve, though a small zip-top bag filled with extra brine works in a pinch as a makeshift weight.

A few other guidelines worth knowing as you get started:

• Use the salt percentage called for in your recipe. Salt isn’t just for flavor here: it’s doing real preservation work by controlling which microorganisms can grow.
• Trust your senses. A properly fermenting jar smells sour and tangy, not putrid. Fuzzy mold (usually blue, black, or pink) means it’s time to discard the batch. A thin white film (kahm yeast) can typically be skimmed off, with the ferment underneath still safe to eat: but when in doubt, throw it out.
• This process is different from infused oils. If you’re exploring other preservation methods alongside fermenting, know that fresh herbs or garlic held in oil at room temperature carry a real botulism risk, since oil creates the same low-oxygen environment that botulism bacteria favor, but without the acidity that protects a proper ferment. Those need refrigeration and a different set of rules entirely.

A Simple First Ferment: Basic Fermented Vegetables

If you want the lowest-stakes way to try this, a simple fermented vegetable jar is the way to start:

1. Slice 1 pound of vegetables (green beans, carrot sticks, cauliflower florets, and radish all work well).
2. Make a brine of 1 tablespoon non-iodized salt dissolved in 2 cups filtered water.
3. Pack the vegetables tightly into a clean quart jar, along with any aromatics you like — garlic cloves, dill, mustard seed, or chili flakes.
4. Pour the brine over the top until the vegetables are fully covered, leaving about an inch of headspace.
5. Weight everything down so it stays under the brine.
6. Cover loosely and set on the counter, out of direct sunlight, for 5–10 days, tasting after day 5.
7. Once it tastes good to you, move it to the fridge.

Once this feels comfortable, sauerkraut is the classic next step:it only requires two ingredients and teaches you the dry-salting method. Here’s my full walkthrough for making small-batch sauerkraut at home.

Always double check the food safety guidelines and info at the National Center for Home Food Preservation.

Troubleshooting Common Ferments

My jar isn’t producing much liquid. Let it sit longer before adding brine, or give the vegetables a firmer massage/press to help release their own juices. If it’s still short after a few hours, top off with a small amount of prepared brine.

There’s a cloudy, bubbly liquid: is that normal? Yes. Cloudiness and small bubbles are signs of active fermentation, not spoilage.

I see a white film on top. That’s likely kahm yeast: a cosmetic issue, not dangerous. Skim it off and make sure everything stays submerged going forward.

It smells “off,” not just sour. Trust your nose here. Sour, tangy, briny smells are normal. A putrid or genuinely unpleasant smell means it’s time to start over.

Where to Go Next

Once you’ve got the basic process down, the best way to build confidence is to work through a few specific recipes:

• How to Make Small-Batch Sauerkraut at Home: the simplest possible starting recipe, using just cabbage and salt.
• 25 Food Preservation Skills Every Homesteader Should Know: see how fermenting fits alongside canning, drying, and curing as part of a full homestead preservation strategy.
• 17 Homesteading Tools Worth Owning: for more on when a proper fermentation crock earns its place in your kitchen.

Frequently Asked Questions

Is fermented food safe to eat? Yes, when the basic rules are followed — using the correct salt ratio and keeping vegetables submerged under the brine. Properly fermented food is acidic enough to prevent harmful bacteria from surviving.

How long do fermented vegetables last? Once moved to the refrigerator, most fermented vegetables keep for several months, continuing to slowly develop flavor over time.

Do I need special equipment to start fermenting? No. A basic mason jar is enough to get started. Fermentation weights and airlock lids make the process easier and more consistent, but they aren’t required for your first batch.

What’s the difference between fermenting and pickling? Vinegar pickling adds acid from the outside. Fermenting (specifically lacto-fermentation) creates its own acid through the activity of naturally occurring bacteria, and produces a live, probiotic-rich food as a result.

Why did my ferment turn out mushy? This is usually from too little salt, too high a temperature, or vegetables that weren’t very fresh to begin with. Using the correct salt percentage and fermenting in a cooler spot (65–70°F is ideal) will produce a crisper result.