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UPDATE 7/26/12: I no longer use whey as a starter for my ferments (learn why here). I also no longer use Mason jars for my ferments (learn why here). I use Fidos and Pickl-Its exclusively and the improvement in the taste and texture of my ferments is unbelievable! I encourage everyone to take a look at the information regarding Mason jar ferments and come to a decision that best fits their family. I will be releasing updated versions of these recipes soon, as it applies to the Fido and Pickl-It jars.
Hi All! I hope you have had a great weekend and are well rested for the upcoming week! Things have been insanely hectic around here, so I’ve just barely been keeping my head above water. I think things will start slowing down in the next few weeks, but for right now, I’m keeping the ferments simple and quick, so I apologize for not having anything new and earth shattering to share!
The Smelly, Yet Awesome, Onion
Simple and quick are exactly the words that can be used to describe this week’s ferment — pickled (lacto-fermented) onions. I don’t really think that I’ve made a ferment that is easier than this. Onions, salt, filtered water, and some brine from your fermented garlic (and/or whey if you’re using it).
Onions are a powerhouse of nutrition. They are similar to garlic in the nutrients that they provide. They are a great source of flavonoids, which are antioxidants that are sometimes referred to as Vitamin P. They are great immune boosters and have many medicinal properties. Because of the flavonoids, onions, as well as garlic, have long been known for their benefits to the cardiovascular system. Citrus fruits, berries, and parsley are other great sources of flavonoids. According to The Worlds’s Healthiest Foods website:
“The flavonoids in onion tend to be more concentrated in the outer layers of the flesh. To maximize your health benefits, peel off as little of the fleshy, edible portion as possible when removing the onion’s outermost paper layer. Even a small amount of “overpeeling” can result in unwanted loss of flavonoids. For example, a red onion can lose about 20% of its quercetin and almost 75% of its anthocyanins if it is “overpeeled.”
Onions also contain large levels of polyphenols. Polyphenols are a certain type of phytonutrient that actually include flavonoids. Onions have the highest polyphenol counts of most veggies, including garlic, leeks, carrots, tomatoes, and red peppers. There are only six vegetables that have been found to have higher counts than onions and those are artichokes, Brussels sprouts, shallots, celery, and broccoli.
The strong smell of onions means that they are rich in are the sulfur-contain compounds, which are important to the cardiovascular system. They help prevent the clotting and clumping of blood platelets. They have also been shown to help cholesterol and triglyceride levels, and even help strengthen the cell membranes of red blood cells. Some studies have shown that onions can even help increase bone density, again due to the sulfur compounds. Other studies have shown that eating onions several times a week can help lower your risk of some forms of cancer. That’s good news for people like me who eat onions pretty much every day. 🙂
Fermented onions are a great addition to all sorts of things. They taste great on burgers and hot dogs, as well as mixed into salads and salad dressings. If you can eat them raw, that will give you the best probiotic boost, but you can also use these to add rich onion flavor to soups, stews, and other heated dishes. I added some brine from one of my batches of pickled garlic, so that added enhanced the flavor and gave the ferment a little kick start. Red onions are going to have the highest levels of flavonoids, but I couldn’t find any for this batch, so I used Vidalia onions. I love Vidalias because they have such a sweetness to them that is only enhanced by the fermenting process.
Pickled (Lacto-Fermented) Onions
makes 1 quart
2-3 onions, thinly sliced
3 cups filtered water
1 tbsp. sea salt (mine is super fine grind)
3 tbsp. pickled garlic brine or whey (optional)
Slice the onions as thin as possible. Pack them into a clean, quart Mason jar (wide mouth works best). Add the salt and the brine from the pickled garlic (or whey), and then fill the rest of the way with the filtered water. Put a lid on tight and shake around until the salt is dissolved. Loosen the lid a little bit and leave at room temperature for 5-7 days. Move to cold storage. Will keep for a long time … if they last that long!
Sources: “Onions“, The World’s Healthiest Foods.
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MMMMMMmmmmmmm I LOVE Love love onions!!! Vidalia’s are my all time favorite too!! I eat onions several times a day (as opposed to per week) so this was good information!!
What’s your thoughts on covering the jar with a cloth as opposed to a lid?
Hey Mike! That would be fine too. The reason that I use a lid with these types of ferments is because I like to shake the jar up once a day or so, to make sure things get submerged in the brine. I don’t know if that’s bad or good when it comes to fermenting, but it’s always worked for me, so that’s what I’ll keep doing 🙂 I only do this with things that are full of brine, like the onions, garlic, Brussels sprouts, etc. Hope that helps! 🙂
why is the whey or pickled garlic brine optional? Can you use water kefir instead (full of microorganisms) if the onions will be your first fermented batch of food?
David – You know, I’ve never used water kefir as a starter for my ferments, however, I know many people who do and have had great success with it. I list the whey as optional, because not everyone uses whey as a starter for their ferments. The garlic brine is also optional, because not everyone will have any of that. I added some of my garlic brine to the onions as both a starter and a flavor enhancer. You can always add more salt, but I’d say give the water kefir a try. Like I said, I’ve never done it before, but I know people who have. Let me know how it turns out and happy fermenting! 🙂
This recipe sounds great! I love onions. Could you add a few cucumbers and carrot slices in also, and make sure to have the whey starter? I’m really wanting to try this.
Hi Sue – You could add whatever you want to the mix! That’s the great thing about fermentation is how flexible it is! Have fun with it!
If you used green onions in place or regular(yellow, red, white) would you still get the same nutritional benefits? Thanks!
I have never fermented green onions before. All onions have similar benefits, so I imagine you would. I’ve just never done it! If you experiment, swing back by and let me know how it goes! 🙂
Hi Jessica– I’m at the end of Day 2 of my ferment– There is quite an odor coming from the onions… Is this normal? Will that decrease over the week? Does mold ever form on the water surface? Thanks!
Hi Mark – Yes, the onions will have a rather pungent smell as they ferment, at least mine did. It shouldn’t be offputting, but it is decidely onion-y. They do mellow out the longer they ferment. I have a batch in my fridge that are about 5 months old and they are not as strong as they were when I first made them. I have never had mold on my onion ferment. As a matter of fact, the only mold I have had was on some ginger shredded carrots that I fermented in a Mason jar years ago. Hope that helps! 🙂
Hi Jessica– Well, it’s day 7. I’m about to transfer the onions to the fridge– Do you keep them in the same container? Do you save all the liquid? Do you rinse the onions at all (worried that they may be too salty). Do you taste them room temp or wait till they get cold?Thanks for the help!
Hi Mark – Sorry for the delay in replying. I have been traveling and just got back. Yes, keep them in the same container and save the liquid. You want the brine to completely cover the ferment, and also you don’t want a lot of head space for air to get into the jar. I don’t rinse the onions — that would wash away all of the probiotic goodness! I personally prefer them chilled on salads and sandwiches. The brine is also good in salad dressings. Hope that helps! 🙂
I just recently started my 1st pickl-it ferment! I chose a mixture of onions & green peppers. I did the ferment w the salt brine. Any suggestions for how long I should leave it in the pickl-it? Also, I would like to transfer the finished product to fido jars so that I can start another ferment. Any idea on the process there? As in once the ferment has completed can I transfer it to the fido & refrigerate?
Hi Fernanda – You will want to let it ferment until the bubbling stops. That will mean that the active fermentation is over. Also, if you have Pickl-It and Fido jars, all you need to do is switch out the lids. I don’t recommend transferring completed ferments to new jars, as it can destroy some of the good bacteria and potentially contaminate the ferment. I’d just switch the lids and you’re good to go! 🙂
I don’t recommend adding any sort of starter to salt-brined ferments because the starter can seriously interfere with the population dynamics of the fermentation. Dutch scientists have proven that “back-slopping” sauerkraut (i.e. inoculating a new batch of sauerkraut with the juice from a previous batch) results in a mushier and less flavorful kraut. This is because the starter culture often contains bacteria from later stages of the fermentation cycle and thus prevents the initial stage from completing correctly. The added acidity from the starter liquid also contributes to this affect as the acidity in the brine is supposed to be a by-product of the initial fermentation phase. That phase is bubbly and odorous but it is required to achieve the proper flavor.
Hi Dave – I agree with you 100%. There are certain stages of proper fermentation that get skipped when a starter is used. I gave up using starters in my ferments about a year ago, once I did some independent research that showed how the pH and fermentation processes were hindered when adding a starter. I do salt-only ferments and everything turns out great! At some point, I will get all of my recipes updated for salt-only fermenting. Thanks for stopping by! 🙂
What actually happens when onions ferment? Are sugars being transformed into something else? If so, what?
Hi Roger – Yes, the sugars and carbohydrates are being broken down and used up in the fermentation process. The bacteria are eating the sugars and then producing lactic acid as a byproduct. This is true of any ferment, whether it be water kefir, onions, or cabbage. I love Cultures For Health’s simple explanation: “Fermenting not only preserves food but also enhances the nutrient content. The action of the culture organisms makes the minerals in cultured foods more readily available to the body. During the fermenting process the bacteria also produce B vitamins and enzymes that are beneficial for digestion.” Hope that helps! 🙂
Hi, I have some potato onions I would love to pickle naturally but I was wondering if I could ferment them whole like cocktail onions. I plan on only fermenting the small ones, maybe up to 1 inch across. Do you think I might need to leave them longer for the ferment to go right through the onion perhaps or ???
Thanks
Hi Jessie – I think that would work just fine. They may need to go a couple days longer, but I don’t see any reason why it wouldn’t work. If you do end up doing it, I’d love to hear how it goes. 🙂
Ok, I made thse with the small potato onions on Feb first and I left them on the shelf until today. They’ve been there through severe heatwaves of 40C and down to about 12C too. I checked them a week ago and they were fizzing! I left them and the bubbles have slowed down so I tried one. BEST ONION EVER! I can’t wait until my husband comes home from work to try one. 2 more large jars going in to ferment now. NEVER again will I pickle an onion! These are easier, healthier and tastier. 🙂
Hi Jessie – Awesome! So happy to hear they turned out well. I find that so many veggies taste better after fermenting. You must try the fermented garlic sometime too. I think it’s my all-time favorite ferment! 🙂
Garlic fermenting now. Stinky stuff but I can’t wait to try it!
I hope you enjoy, Jessie! It’s totally worth the stink! 🙂
Can’t wait to try this! So…if the fermenting process is what’s supposed to be producing the acidity, would it be a bad idea then, to add a few tablespoons of ACV at the beginning?
Hi Cindi – I would not add any ACV into your ferment. Proper fermentation needs to go through a series of steps and adding vinegar would inhibit the proper process by altering the pH of the ferment. Cheers!
Thanks, Jessica…I’m starting the onions now! 🙂
I hope you enjoy Cindi! 🙂
Hi, I don’t have any garlic brine or whey, how do I substitute it with even you say it’s optional. Thanks
Joanne – You can leave it out of this recipe. I actually no longer use whey or brine as starters for my ferments because they prevent all of the proper stages of fermentation from taking place. I now just use a salt brine, made with 19 grams of sea salt to 1 quart of water. I updated the lactofermented onion recipe and you can find that new version here: https://www.deliciousobsessions.com/2012/11/52-weeks-of-bad-a-bacteria-week-34-lactofermented-red-onion-recipe-updated-for-the-pickl-it/
Hi, where do I get garlic brine or whey? Is it easy to make own garlic brine? How do I do it? Thank you.
Joanne – You get garlic brine from fermented garlic. Recipe here: https://www.deliciousobsessions.com/2012/01/52-weeks-of-bad-a-bacteria-week-1-pickled-lacto-fermented-garlic/. It’s easy and delicious! 🙂
I was wondering if you ever fermented whole shallots? How long do you think they need to sit. I have read that some say a week is good where others say a month or more. What percentage on the brine solution 3%, 4%,or 5%? I am so confused, your input is appreciated.
Hi Joann! I have not fermented shallots. I think they could be done the same was as the onions. I have an updated fermented onions post that might be helpful: https://www.deliciousobsessions.com/2012/11/52-weeks-of-bad-a-bacteria-week-34-lactofermented-red-onion-recipe-updated-for-the-pickl-it/. Also, are you on Facebook? If so, I highly recommend my friend Lisa’s group: https://www.facebook.com/groups/CounterCultures. She is my #1 fermenting guru! 🙂
Why didn’t you just change the recipe instead of saying why you were not using whey and mason jars or put that into the recipe??
Hi Leslie! Thanks for stopping by! I chose not to change my old recipes because there are still a lot of people who prefer to ferment with whey and mason jars and I don’t want them to lose access to recipes that they like. I did continue on with the series and made new versions of some of my popular ferments using my preferred method. For example, this is a new onion version: https://www.deliciousobsessions.com/2012/11/52-weeks-of-bad-a-bacteria-week-34-lactofermented-red-onion-recipe-updated-for-the-pickl-it/. Hope that helps!
How smelly is this? I have fermented many different vegetables but yet to do onions. Unfortunately here in phoenix where it is currently 112 outside it is hard to find a place that stays below 74 degrees or less without major temperature swings. Then only place I have to keep it between 70-74 degrees is a small closet where my wife keeps her canned fruits. It also happens to be in the bedroom. I really do not want to make that smelly. Thanks
Hi Matt! Thanks for stopping by. I would say these onions and the fermented garlic can get the most smelly. I think the onions are even more smelly than the garlic. Based on my past experience, I would definitely be hesitant to keep it in the bedroom. I typically had mine going in our dining room and it would be rather strong once it really got going.