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I am slooooooowly going through my old ferments and getting them updated for the anaerobic fermenting vessels. I will, at some point, get them all updated. It’s just going to take me awhile! 🙂
I did get my original pickled onion recipe updated and that is what I’m sharing with you this week. This recipe is SO easy! Two ingredients are all you need – onions and brine (I guess brine is technically two ingredients).
You can also make these fancier by adding some garlic or fresh herbs. I meant to add garlic and thyme to my batch, but I was crying so hard by the end of slicing all those onions that I completely forgot. My health food store had a great price on red onions recently, so I stocked up. Those are some of the strongest red onions I’ve ever sliced. I made two slices in my first onion and was already crying! Tears and sharp knives are not a good combo!
If you don’t like red onions, feel free to use a different variety. These “pickled” onions are delicious in salads, on sandwiches, with eggs, on pizza, and more. Really, you can use them any way you would regularly use onions. Delish!
I made a two-liter jar, but you can make more or less, depending on how much you like them. They will last upwards of a year in cold storage, so it’s a great chance to make a big batch. They do get better with age. The picture above I took before the fermenting got underway. I thought they were much prettier at the start than they were once they were fermented. 🙂
Lactofermented Red Onions (Updated for the Anaerobic Jars)
Ingredients
- 5 red onions – mine were on the small/medium side, so you may only need 3 if they’re really big
- Fresh herbs (optional)
- Fresh garlic (optional)
- 2% brine (19 grams of sea salt per 1 quart of filtered water)
Instructions
- Make your brine and let cool to room temperature. For a 2L anaerobic fermenting jar, I needed exactly one quart of brine.
- Slice your onions (have tissues ready, and please, don’t cut yourself!)
- If you are using fresh herbs and garlic, place those in the bottom of the jar. Then pack your sliced onions on top and pack to the shoulder of the jar.
- Add your weight.
- Pour your brine over the onions, filling to the neck of the jar. You want to make sure you leave at least an inch of headroom between the top of the brine and the lid.
- Add your airlock and close the lid. Wrap the jar in a dark towel to keep the light out. UV light destroys all the good little bacteria we’re trying to cultivate!
- Leave at room temperature until the active bubbling stops. Depending on the temperature of your house, this could be anywhere between 5 and 10 days. My house is starting to cool off now that it’s fall, so it took 8 days at room temperature. When the bubbling is done, move to cold storage and enjoy!
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Can I just use this same recipe for the Fido? How many Tbs are 19 grams of salt? Are you using pink himalayan salt? I want to make this and some kraut tomorrow, been putting it off and I love your weekly series.
Lori – You could do the same in a Fido jar, but I don’t like fermenting in the fidos, because there is no way for the gasses to escape and the CO2 buildup damages the LABs.
In regards to the salt, you can use whatever sea salt you have on hand. Mine is a super fine grind pink Himalayan salt – it’s almost like a powder. I don’t know a precise measurement for it, because I just always use my scale. Next time I make some, I will try to make a note of the tbsp. measurement, though it won’t be that accurate for people because their salts are all going to be different. Hence why it is best to weigh it. Does that help at all? 🙂
Is it normal for the red onions to lose their color and turn greyish after a month or two in fidge?
Ho Lola – Yes, I am noticing mine are really starting to fade out — this last batch was the longest I’ve let stay in the fridge. Normally I eat them quickly, but for some reason, I haven’t been in the mood for onions. Weird. The brine is now more of a grayish purple color. They still taste good though! 🙂
I have a question. If you can use these like regular onions, will it kill the good bacteria if they are heated. I am trying to get fermented foods into my hubby, but if heating kills good bacteria this won’t work less they are served raw. Going to start a batch now. Thanks for your blog!! Making these onions and fermented garlic today!
Hi Rebecca – If you want to preserve the probiotic benefit, then yes, you would want to avoid heat. I like to put them on sandwiches, wraps, salads, etc. The uses are many! Enjoy! 🙂
am I missing something? where does the culture come from? Did you miss a step where whey from yogurt making is added?
Hi John – No, you didn’t miss anything. Starter cultures are not needed for most fermentation. The good bacteria is prevalent in the foods we ferment and the environment in the jar is all you need to get them going. There may be a few ferments that do require a starter culture, but the vast majority of veggie ferments do not. You can read more about why I stopped using whey and starter cultures in my ferments here: https://www.deliciousobsessions.com/2012/02/by-the-whey-side-why-ive-stopped-using-whey-in-my-vegetable-ferments/
thanks so much for the reply, and for your site! It’s so very informative and gives me lots of ideas to think about.
My pleasure! Thanks for the kind words! 🙂
Could you skip the brine and ferment the onions in the same method used for sauerkraut? IE. add the salt directly to the onions and crush the juices out of them until the onions are covered by their own juices?
Hi Paul – Most likely you wouldn’t get enough liquid from the onions. You are certainly welcome to experiment though! 🙂
Hey, just wondering if normal white onions would work and still taste good? I have a lot right now but wanted to ask first. Thanks so much for your help!
Yes! Those would work just fine. I’ve made them both and they are equally delicious! Enjoy! 🙂
Thanks so much for your help! I am a little concerned though because there aren’t bubbles forming at the top of of the brine like my previous ferments. Is this normal for the onions? Maybe I put too much salt in it?
Thank you!!!
Hi Sheri – When you tap on the side of the jar, do any bubble come up from the bottom? If not, it is probably done fermenting. Once it is completely, the active bubbling stops and you can move it to cold storage.
This may be a silly question but what is the weight? And you can store this in cold storage with an airtight seal is that correct? I have only made pickles but we ate them in the same week so I was wondering how to do it for long term storage ie 1 year
Hi Heather – I don’t have a weight for the onions. Next time I make these, I’ll make sure to weigh them first. Yes, you store this in the fridge in the same jar you ferment them in. In cold storage, they will last at least 6 months.
Hi Jessica,
I ferment a lot of veggies on a regular basis but I had never thought of fermenting onions and I must say this is an absolute delicacy ! (I add cumin or caraway seeds)
I love onions but they may be difficult to digest. This way I can enjoy lots of them without trouble, thanks for the idea and for all there is on your website !!
Awesome! So glad you enjoyed them! 🙂
I love this idea! I don’t have the anaerobic jar or a weight to use though. Is there any way to do this in a mason jar with maybe a towel over the top?
Hi Jamie – Yes, you could do it in a Mason jar. I have not tried it that way, but it should work fine. I would use a lid rather than a towel. The goal of proper fermentation is to keep the oxygen out of the ferment. Using a towel would allow oxygen in. Hope it works out! 🙂
Just wondering after the bubbling dies down and you say cold storage..is that considered to be a fridge/ cantina?
thanks for the recipe xo
Hi Katie – The fridge is most common, but I do know folks who have a cool root cellar where they store their ferments. I hope you enjoy! 🙂
Hi Jessica,
I am new to your blog. Found you on Renee’s RGN. I am regular follower on RGN. These pickled onions look great! I am new to fermenting so I have couple of questions….if we use the anaerobic jar that you linked, will there be no need to burp the onions everyday while fermenting? Alternately can I use a Fido jar and burp them everyday? Thanks a lot!
Hi Swarna! Welcome! I just love Renee! 🙂 Yes, with the anaerobic jars that I linked to, there will be an airlock that removes the need to burp. You could burp the Fido jars, though to be honest when I was using those exclusively, I rarely had to burp them. I’m not sure if it was just my own house environment, but there was rarely enough pressure to require the daily burping. Some people have told me that they feel the Fido jars burp themselves too, as a small amount of gas escapes between the seal and the jar, though I think it really depends on what you are fermenting and what the temperature inside the house is (the hotter it is, the faster it ferments, the more pressure that can build up). Hope that helps! 🙂
can the brine be drank after fermentation process
Yes! Well, if you like the taste of it. I use it in salad dressings for flavor. A great way to use up the brine which is rich in beneficial yeasts and bacteria!
where does the lacto come into this, I thought lacto was from milk?
a quick google shows I am wrong 😉
Hi Ando! It’s a common misunderstanding! People immediately think of lactose when I mention lacto-fermentation. The “lacto” in regards to fermentation actually comes from the lactic acid.
I love fermented onions. I usually put them on sandwiches when I need a really tart addition to something savory. I am more than excited to try this when I go to make my next fermented project. Thank you for sharing this great recipe! I’m hungry already.
Hi Billy! They are one of my faves! Hope you enjoy and thanks for stopping by! 🙂
Hello, and thank you for the recipe! I just finished my first batch, and was wondering whether it’s possible to use old brine to make a new batch.
Hi Kristin – Thanks for stopping by! Yes, you could use some of the old brine as a starter if you like. I don’t tend to do that myself, but there is no harm in doing so. Enjoy!! 🙂
Thanks for the recipe and inspiration. I learned (alton Brown) that if you leave the root end on the onion while slicing it, you’ll reduce the tears. 😂
Hi Nancy! Thanks for stopping by! I learned that too but ALWAYS forget. I don’t know why it’s so hard to remember not to chop it off. 🙂 P.S. I love Alton Brown! My favorite food celebrity by far. 🙂
Keep yourself from crying by using a cheap pair of swim goggles. Just make sure they aren’t tinted! Oh and breath though your mouth. I always cut onions this way… works like a charm!
Hi Tammy! I’ve heard that suggestion before. I have never tried it though. Thanks for stopping by! 🙂
Just diced a pund of onions finely for som lacto-fermented onion sauce I’m experimenting on, All the while I was sobbing like a baby 😭 Onions now fermenting in tears and salt….
Hi Villiam! LOL! I can relate! Those onions can really get you! Hopefully the end result is still delicious. 🙂
Do you eat them from the jar or with different foods examples please.
Hi Carla – I typically add these onions to things like salads, sandwiches, or wraps. I’m not a fan of eating onions by themselves. You could truly use them any way you normally use onions, keeping in mind that heat will destroy the probiotic benefits. Enjoy! 🙂
Can I use a Harsch fermenting crock with the water seal?
Hi Rick! Thanks for stopping by! Yes, you can! Enjoy! 🙂