Fermented Lemons

Do you like preserved lemons? I do. If you do too, you’ll want to read on, especially if you’re the type of person who likes an easy fermentation project.

I always seem to crave preserved/salted lemons when I don’t have any around, and, it can be hard to find them if you don’t live in a big urban area with access to Middle Eastern markets. Making your own, while a fun experiment, takes months. So, a few years ago I had an idea for a workaround.

The best lemons come from my Grandmother’s tree in Arizona.

Instead of just burying lemons in salt, I thought why not ferment them? It turned out to be a fun kitchen hack that’s pretty darn close to traditional salted/preserved lemons, but without all the extra salt you have to rinse or soak off. It’s also done in a couple weeks, instead of months, and, just like salted lemons, it’s also shelf stable near indefinitely. As a bonus, depending on the method you use to make them, fermented lemons can also come with along with an useful byproduct in fermented lemon juice, as the liquid isn’t indelibly salty as with traditional preserved lemons that are buried in salt. 

The only real tricky thing to wrangle is the paradox of choice, because there’s a lot of different ways you can go about fermenting lemons. I’m going to go over the most useful methods I’ve found, and explain the differences and trade-offs between the two, along with a sub-method or two. 

Fermenting in Brine 

Lemons will ferment easily in a traditional brine ferment. To do it, take lemons and quarter them, put them into a jar, and pour over a solution of 3% brine. Weigh the lemons down with something (a clean stone is fine) and allow to ferment for two weeks, or until sour to your liking. This will make fermented lemons, but the residual juice in the lemons isn’t worth harvesting (at least for me) since it’s watered down. 

Fermenting only the rind in brine 

If you cut the flesh and seeds from the quarters of cut lemons, you can ferment the rind only, saving the fresh lemon juice for another purpose. This also allows more lemon rind to fit into a jar, which will give you a higher yield. 

Fermenting Under Vacuum 

The traditional method works, but my favorite is to ferment the lemons under vacuum, for a number of reasons. First, vacuum fermentation means that as the ferment isn’t exposed to air, it’s basically impossible for it to mold. Using vacuum fermentation, I have never seen any sort of mold or kahm yeast develop. To my knowledge, it is the safest way to ferment most things, and I know some chefs (Jeremy Umanksy, author of Koji Alchemy) who use it exclusively for all of the ferments sold in his restaurant Larder. You can seal up the lemons and forget about them for a year at room temperature and they’d probably be better for it. 

The lack of air exchange in vacuum fermentation also means that the lemons, along with the delicious, aromatic oil in the rind, are trapped together, a forced marinating and exchanging of flavors that happens as the fermentation takes place. In short, it’s going to smell and taste extra lemony since none of the aromas have ever been lost to air exchange from removing the lid of a jar. This might sound a little hokey, but it’s true. I discussed it in my appearance on Daniel Vitalis’s podcast Wildfed a few years ago in the episode “The Final Frontier of Food”.  

With vacuum fermentation, the lemon’s natural juice hasn’t been diluted with water and it’s only slightly salty, so you can also strain it and use it in cooking or for making condiments, dressings, etc. Fermented lemon juice is pretty cool, it’s great spritzed on some fish or swirled into a sauce, vinaigrette or used anywhere you’d use fresh lemon juice. 

Finished vacuum fermented lemons cooked sous-vide, and fermented lemon juice removed after fermentation. 

Adjusting the texture of the fermented rind

One of my favorite things about traditional salted lemons is their tender bite. Fermented lemons won’t have the same soft chew of salted lemons at first, but it’s easy to get around. To soften the texture a bit to for use as fermented lemons, I sous-vide the finished, fermented lemons, or steam them very gently until they’re just tender, the former being my first choice. If you’re putting the lemons in a stew, such as a tagine, you just can just simmer it a bit longer until the lemon pieces are tender. 

Finished, cooked and diced fermented lemons. Use them as a sprinkle wherever you’d use preserved lemons.

Use ideas 

You can use fermented lemons in any recipe that would call for preserved lemons. 

Tagines

The North African stew is probably the best-known place where you’ll find preserved lemons. Other soups and stews especially complex things like curries can also work. 

Dips and spreads

Adding a sprinkle of finely diced, cooked, fermented lemons will add a great lemony bite, artichoke dip is a good example. The chopped rind can also be mixed in things that will be buzzed in a food processor. Borani esfenaj with fermented lemon would be great. 

Just about anywhere you’d use lemon zest

Pan sauces, stuffings, etc. I worked at one place where we made a compound butter for steak made from blending preserved lemon, rosemary and black pepper in a food processor. 

With Leafy Greens 

Bakula, a dish of mallow and/or purslane cooked with garlic, cumin, paprika, preserved lemon and olives is one of the most famous wild food dishes of Morocco.

A Moroccan classic. In my book, I describe arguably the most heavily consumed dish of wild plants in Morocco. That dish, known as Bakula, Bkula, or Baqula (and likely more names) I first read about in an E.U. academic thesis quantifying specific species of wild plants consumed in Europe and the Mediterranean. It’s a simple dish of cooked mallow, purslane, or a combination, seasoned with cumin, paprika, olives and preserved lemon. In short, just try tossing some finely chopped, cooked fermented lemon rind in with cooked leafy greens.

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4.25 from 4 votes

Vacuum Fermented Lemons

Simple, fermented lemons made by fermenting in a vacuum bag.

Prep Time10 mins

Fermentation time14 d

Course: Condiment

Cuisine: American, Moroccan

Keyword: Fermentation, Lemons

Equipment

• Vacuum sealer
• Vacuum bag, gallon size

Ingredients

Brine fermented lemons

• 2 lbs Organic lemons or meyer lemons
• 27 Grams Kosher salt

Instructions

Sealing and fermenting

• Cut the lemons into quarters the long way, then combine with the salt and seal in the vacuum bag. Allow the lemons to ferment in the bag for 2 weeks, or until sour to your liking.
• As the fermentation progresses, the bag will inflate from carbon dioxide. While I've never had a bag burst, I do cut the corner off of the bag as needed to release carbon dioxide, resealing the cut corner without using the vacuum to keep the lemons contained.

Trimming

• After the lemons are fermented, remove them from the bag, put them rind-side down on a cutting board, and, using a sharp paring knife, cut away the pith and seeds and discard. If you used the vacuum method, you can squeeze the capillaries and pith to extract fermented lemon juice.
• From here, the lemons are shelf stable and can be held in the refrigerator, or water-bath canned in their brine if you used brine. Canning in brine will also tenderize the rind, which is a nice bonus. Do not can lemons in their juice, which could become bitter-save that for another fresh purpose like salad dressing.

Tenderizing the rind

• Finally, you need to heat the rind long enough for it to become tender. My favorite way to do this is to seal in a vacuum bag and cook sous vide at 150 F for 2 hours, but you can also steam them.

Print Recipe

4.25 from 4 votes

Brine Fermented Lemons

Simple, fermented lemons made by fermenting in brine.

Prep Time10 mins

Fermentation time14 d

Course: Condiment

Cuisine: American, Moroccan

Keyword: Fermentation, Lemons

Equipment

• Nonreactive vessel, such as a half gallon wide mouth mason jar with a plastic lid

Ingredients

Brine fermented lemons

• Organic lemons or meyer lemons
• Kosher salt As needed
• Filtered water as needed

Instructions

Brine fermented lemons

• Make a 3% brine solution by mixing 30 grams of salt for every 1000 grams of water.
• Cut your lemons into quarters and pack into a large jar, such as a half gallon mason jar, or a couple quarts. Cover the lemons with the brine, weighing them down with an object in the jar like a clean stone. Allow the lemons to sit at room temperature and ferment for 7-14 days, or until sour to your liking.

Trimming

• After the lemons are fermented, remove them from the jar, put them rind-side down on a cutting board, and, using a sharp paring knife, cut away the pith and seeds and discard. If you used the vacuum method, you can squeeze the capillaries and pith to extract fermented lemon juice.
• From here, the lemons are shelf stable and can be held in the refrigerator, or water-bath canned in their brine if you used brine. Canning in brine will also tenderize the rind, which is a nice bonus. Do not can lemons in their juice, which could become bitter-save that for another fresh purpose like salad dressing.

Tenderizing the rind

• Finally, you need to heat the rind long enough for it to become tender. My favorite way to do this is to seal in a vacuum bag and cook sous vide at 150 F for 2 hours, but you can also steam them.