Canning and Preserving Class
Lesson 5: Lacto-Fermentation
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Why This Method Works

This is the gist of the lacto-fermentation process:

  • slice, chop or shred some clean veggies (like cabbage, carrot, radishes, etc.)
  • add salt
  • give them a little massage
  • place the veggies in an UNSTERILIZED jar along with their own brine - the result of the salt and massage
  • weigh down the food bits
  • loosely screw on a lid
  • set the jar on a plate

The process of lacto-fermentation probably seems so counterintuitive given everything we've learned about temperature and spoilers and scary bacteria, that I would understand completely if it made you uneasy.

But I swear it is indeed safe and here's why:

Yes, there are bad guy bacteria, but there are also good guy bacteria. It's the good bacteria that are the stars of this process. These good bacteria, the process' namesake Lactobacillus, live on the surface of fruits and vegetables and are more salt tolerant than the bad guys. The salty brine starts to kill off the bad bacteria, while the good bacteria begins its job of converting the lactose and other sugars in the food into lactic acid. The low pH environment that this increase in lactic acid creates, is inhospitable to bad bacteria. It also gives fermented food its signature tangy taste. The good bacteria just continue to grow and multiply the longer the jar stays at room temperature. Which is a GOOD thing! :)

Another benefit of these helpful bacteria, is that they are probiotic. In fact Lactobacillus is the most common probiotic found in yogurt and fermented foods. They help balance the good and bad bacteria in your gut and help move food through your digestive system. People pay big money for store bought probiotic capsules when all they have to do is roll up their sleeves and give some vegetables a massage. :)

Hopefully you will enjoy the process and taste enough to make lacto-fermented foods a staple on your plate.

NOTE: Because of the high acidity of lacto-fermented foods, use it as a meal supplement and not a meal in itself. 1/4 cup a day is a good rule of thumb.

Tools & Equipment

Here are the tools you'll need to make each recipe in this lesson:

Lacto-Fermented Green Beans

  • scale
  • colander
  • medium bowl
  • measuring spoons
  • measuring cup
  • (x2) clean quart jars*

Garlic Sauerkraut

  • scale
  • cutting board
  • chef's knife
  • large bowl
  • grater
  • peeler
  • measuring spoons
  • (x1) quart jar w/ plastic lid*
  • (x1) 4oz jam jar without lid*

*It's not necessary to sterilize the jars. Washing and drying them is enough as the low pH environment that the good bacteria and lactic acid create, is inhospitable to bad bacteria.

Lacto-Fermented Green Beans

This recipe is so easy, and the results are so mild and delicious, it makes me want to plant my entire yard with green beans. But then I remember I also love peppers, and carrots, and tomatoes, and...


  • 2 lbs (907 grams) of fresh green beans
  • 3 cups of filtered, distilled or de-chlorinated water*
  • 1 tbsp kosher salt

*The chlorine in unfiltered tap water can kill the good 'lacto' bacteria, inhibiting proper fermentation. To de-chlorinate tap water, leave the amount you need out on the counter (uncovered) overnight and the chlorine will evaporate. If you forget to do this ahead of time, use filtered water or run out and buy distilled water.

Sort through your green beans and pick out 2 pounds of the crispest, youngest and best looking beans.

Make the brine by dissolving the salt in the 3 cups of water.

Snap or cut off the ends of the beans.

Lay the jar on its side and begin stacking the beans into the jar.

Fill the jar until it's no longer easy to add more.

Stand the jar straight up and add as many more beans as possible.

If your beans are shorter than the jar, it's ok to cut them and add shorter pieces to fill in the space.

Just continue to shove the shorter pieces in...

Until the jar's completely full.

You want to leave about 1/2" headspace so there's room to cover the beans with the brine.

Repeat for the second jar.

Fill the jars with the brine.

Loosely screw on the lids.

They need to be loose enough so that brine that is displaced by the gasses created by the fermentation process can escape the jar as needed.

Place the jars on small plates (to catch the displaced brine) and put them in a dark and cool spot in your kitchen that's at room temperature and out of the way. Leave them for 2-3 days.

After one day, this is how much brine had been pushed out from one of my jars.

Once a day for the 2-3 days at room temp, unscrew the lid and check for signs of the fermentation process. Small bubbles should be forming and the brine will be slightly darker.

If any beans have floated up, push them back in place using the back of a spoon.

At the end of day two, this is what my brine looked like. Much cloudier than just the day before. This is what we want! It means the lacto-fermentation process is indeed taking place.

This is what the top of my brine looked like on day 3. Perfectly murky looking! Now it's time to put the lids back on and move the jars to the fridge.

I would let them continue their slower fridge ferment for at least another two weeks before serving them. They will last in the fridge for up to 1 year! (There are more detailed storage tips at the end of this lesson.)

Next up, we're going to make a lacto-fermentation staple that has been around for hundreds, if not thousands of years: Sauerkraut!!

Sweet Garlic Sauerkraut

Making sauerkraut is my all time preserving favorite! It's quick, easy, delicious to me, and it's naturally occurring probiotics are so good for the ol' gut! That's a lot of benefit from a couple of humble veggies.


  • 1 medium head of fresh green cabbage
  • 2 carrots
  • 2 cloves garlic
  • 1 tbsp kosher salt

The best way to ensure success your first time out of the sauerkraut gate is to measure the ingredients. The general rule of thumb is 1 3/4 lbs of veggies for each quart jar. Today, we'll just be making one quart of kraut, so we want to end up with 1 3/4 lbs of ingredients.

Before you begin, zero out your manual scale or find the tare weight of the bowl you'll be using to weigh the kraut ingredients. The weight of my bowl was: 2 lbs 13 oz (rounded up).

Next, peel and grate the two carrots.

Remove the skins from the 2 garlic cloves and finely chop them.

Add the carrot and garlic to the bowl.

Weigh your cabbage so you have an idea of how much of it you'll have to use. I ended up using almost 3/4 of mine, minus the core.

Before you start cutting up your cabbage, remove one of the large outer leaves and set it aside. We'll be using this later to help hold down the grated ingredients in the brine.

Quarter your cabbage. Then thinly slice two of the quarters, not including the core. Chop those slices into smaller slices still.

NOTE: The thinner you cut the cabbage, the softer the sauerkraut will be. If you like crispier kraut, cut your slices a bit thicker.

For those of us with digital scales, it's time to do a bit of math. Add 1 3/4 lbs (= 1 lb 12 oz) to the tare weight of your bowl. You want to add chopped cabbage to the bowl on the scale until you reach that total (in my case 4 lbs 9 oz). That means you'll end up with 1 3/4 lbs of ingredients!

Like so!

Measure out 1 tablespoon of kosher salt (3 teaspoons) and sprinkle it on the ingredients in the bowl.

Using clean hands, you're going to 'massage' the cabbage for 4-6 minutes to start the process of bringing the brine out of the veggies*. If working with your hands is difficult, it's also ok to just stir the salt into the veggies, cover the bowl with a clean dish towel, and leave it to sit for a couple of hours. The salt + time will do the work for you.
*NOTE: This isn't necessary (or possible) to do when leaving veggies whole, like we did in the last recipe, because they wouldn't sweat enough moisture out through their whole uncut skins to create enough brine. That's why we have to help them out by adding some.

As you message the ingredients, more and more brine will emerge. You want to end up with about the same amount of brine as in the above photo.

Use the plastic jar lid as a 'cookie cutter' to cut out a circle from the large cabbage leaf we set aside earlier. We are going to use this in a minute.

Now it's time to fill the jar!

Using a clean hand, start filling the jar with the future sauerkraut.

Use a spoon back to tamp the kraut down at the bottom of the jar.

As the jar gets filled, you can use your fist to tamp it down.

All of the veggie mix should fit into the jar with 2 - 3" of headspace.

Pour the brine from the bowl into the jar.

Use your finger to push any run away cabbage or carrot bits back down into the brine.

Here's a side view update. :)

Now it comes time for the little cabbage circle to shine.

Place it in the jar so that it completely covers the veggies and prevents them from sneaking up the sides of the jar.

Next up, is the 4 oz jam jar. This little guy is clutch for keeping all the goodie bits down in the brine where they belong.

Place the small jar into the opening of the quart jar, so that the bottom rests on the cabbage circle we just added.

Gently press the 4oz jar down into the quart jar with the plastic lid and screw the lid lightly into place. Remember we can't tighten the lid all the way because the brine displaced by the gasses created during the lacto-fermentation process need a way to escape the jar and they won't be able to do that if the lid is all the way tight.

Place the jar on a small plate (to catch the displaced brine) and move it to a dark and cool spot in your kitchen that's at room temperature and out of the way. Leave it out for 3-7 days before transferring it to the fridge for long term storage.

And don't forget to label it so you can accurately keep track of its progress!

Storage Tips

The best (and only) place to store your ferments once they've been at room temperature for 2 - 28 days (the time at room temperature depends on the recipe) is in the fridge. (Or the coldest area of a root cellar if you're lucky enough to have one.)

Different areas of the fridge are slightly different temperatures, so placement will affect the pace at which your foods continue to ferment.

The shelves in the door are the warmest area of the fridge, so if you'd like to reach a more 'fermented' flavor quicker (i.e.: you plan to eat them within 1-2 months and you love a robust ferment tang), put your jars there.

If you expect to keep your ferments for the long haul before digging in (11-12 months) and want a milder flavor, place the jars in the back of the top shelf. This is the coldest area of the fridge.

Try and keep all the food bits below the brine line so that they don't dry out. They tend to sneak up the sides of the in-use jars if you're not vigilant.

Fermented foods will last for up to 1 year if stored in the fridge and for 3-4 months in a root cellar.

NOTE: Make sure to tighten the jar lids before placing it in them the fridge for storage.


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