What is it about cooking with onions that brings tears to our eyes?
I’ve done a lot of cooking in my day, and I was determined to learn the reasons for this, as well as how to combat them in my own kitchen.
Read on for a quick explanation of the chemistry involved in the process, my methods for deducing the best tear-free chopping techniques, and my top five tips for prepping onions without crying.
Chemistry that Makes You Cry
According to Everyday Mysteries from the Library of Congress, when it comes to the chemical composition of onions, we know that they produce a chemical compound called syn-propanethial-S-oxide. Cutting an onion releases this gas.
When it wafts up towards your eyes, it bonds with their natural moistness, creating sulfuric acid. And sulfuric acid burns.
Hence, we cry.
Seeking Sweet Relief
I went about my research very unscientifically, by asking other chefs, family, and friends for their best tips.
And let’s not forget the many lovely church ladies in my small Gulf Coast hometown – they had plenty of advice to share as well.
Why did I focus on gathering anecdotal evidence from these individuals? Because they’re the best cooks I know!
Examining the Evidence
What did I learn in my research? A lot, some good, some bad.
Let me fist dispel some myths: I was told to burn a wooden match, blow it out, then hold it between my teeth and breathe through my nose as I sliced. Or to bite a toothpick, place an ice cube in my mouth, or chew gum while I chopped.
I’m just not that coordinated!
I was also told to keep a lit candle near the cutting board, run a small fan to blow away the gases, and run cold water in the sink while I sliced the vegetables.
I think my favorite idea came from a neighbor, who always cuts her onions on the front porch so she can visit with neighbors as she works.
I imagined my neighbors leaving my house, their eyes streaming with tears, and decided I’d rather not try this method.
Chef-Centric Test Run
Next, I bought ten pounds of onions and commenced to chopping.
As the result of what I must say was a valiant effort, after dicing and slicing many onions, and two full boxes of tissues later, I am sorry to say none of these ideas worked well for me.
So, I decided to turn instead to methods that have actually proven to be useful for many experienced chefs and cooks.
The Bottom Line – How to Stop the Tears
Take a look at the top five winning tips, for the best ways to steer clear of onion tears:
1. Your Refrigerator or Freezer is Your Friend
It turns out that placing an onion in the freezer (for a quick 10 minutes) or refrigerator (for just 30 minutes before cutting) works. It keeps the cells from “exploding” into the air as quickly as a room temp onion can.
2. A Stovetop Ventilation Fan Can Work Wonders
Try placing your cutting board securely onto your front stovetop burner. Make certain it is off and cool first, and turn your hood or ventilation fan on high. It helps to redirect the gases away from your eyes.
3. Don’t Cut the Root End
Seriously, here is where we get to the root of the problem. Chefs will tell you that the tear-jerking sulfur compounds are concentrated here. Once you cut into the root, they billow into the air – and your eyes. Review how to prep an onion, so you can cut with skill and agility!
4. Always Use a Sharp Knife
It’s well worth investing in a good knife sharpener and honing steel to keep your knives safe, and more efficient to use. The sharper the knife, the less you will smash the cells of the onion, or tear up. Sharp knives make your work safer, quicker, and easier.
5. Try Onion Goggles
Yes, there is such a thing. These eye-saving gadgets prevent noxious fumes and gases from getting near your eyes. A wide variety of styles and colors are available on Amazon.
If you are an eyeglass wearer, try chemistry goggles instead, to enjoy the same benefits – they’ll fit right over your glasses.
Sometimes the best cooking tips come from food scientists, while other times they’ll originate with your family, neighbors, or even your friendly resident food blogger. But the real test comes from you.
Whatever method works for you is always going to be the best, right?
So go forth without the fear of tears, and start enjoying onions that are caramelized, sautéed, stuffed, sensationally baked into tarts, or made into rings in your own kitchen.
I can’t wait to hear all about your best onion cutting tips, and how these work for you, too! Share with me in the comments below.
Photo credits: Shutterstock. ORLBUE product photo courtesy of ORBLUE.
About Marla Tetsuka
As a professional chef, author of multiple cookbooks, and graduate of the esteemed Le Cordon Bleu College of Culinary Arts, Marla brings a professional touch to the community that we call Foodal.
Hi Marla thank you for taking the time to do this!
I always just wear old ski goggles (kind of like the kid up in that photo) and my wife doesn’t miss this opportunity to make fun of me!
I turn on the kitchen fan and it helps a bit. I have also tried the running under cold water, it seems to only help a little.
I notice when I cut them after they have been in the fridge they don’t make me cry. I figured it was because they had already been cut and the stuff inside of them was all gone. Little did I know the COLD is actually helping!
Also you reminded me that the wife asked me to get the knives sharpened, like a month ago so I better get on that.
Here’s to no more goggles and no more tears!
Hi there! So glad you shared your fun kitchen “ski goggle” story with us. I always enjoy hearing about personal cooking experiences. And yes, the cold does help. Happy chopping.
Okay, whenever I take an onion out of my pantry to use, I peel it and then put it in a bowl of cold water for at least 10 minutes. After I take it out of the water, I am able to slice and dice it up without any tears. I don’t know where I got the idea from, but it has been working for me.
Also, I’ve noticed that whenever I needed to chop any leftover bits that was stored in the frig, that I wouldn’t cry, so there is something behind putting all of mine in the frig for a bit before cutting it. I might just start using this method more often.
Thanks for your tip. Ice water may be another good way to chill them. Especially helpful if refrigerator or freezer space is tight.
Wow, you went the extra mile here, chopping ten pounds of them! I don’t think I could hack it.
I didn’t know about protective eye wear for onions, ha ha. That’s great!
Number three is a great tip as well. I didn’t know that, but you can bet that I’ll be adhering to it from now on. Thanks for the good read. I love stuff that makes my life a little easier, especially in the kitchen.
I’m happy to be given a good reason to play with my food anytime! Besides, all of my neighbors received a good supply of sliced onions.
Woah… I never would’ve thought that an onion goggles would seriously be invented -although it is useful, it seems… awkward? Anyway, about the freezer/refrigerator method. while effective, I don’t really recommend it. It usually leaves an odor in the refrigerator and sometimes it even affects the taste of the food in the refrigerator (or do I just leave it there for too long?) That’s all ^^ Thanks for the other tips! (Seriously helpful, I can’t cut them without crying for an hour after <<This is why I'd rather let my food taste lacking than put onions in it. lol)
Wearing a set of goggles does sound funny, but if you think about it the idea is sound. They do protect your eyes and prevent tears. Who knows? It could become a new fashion trend, ha-ha. Try only keeping your onion in the refrigerator or freezer just long enough to chill. That shouldn’t create any odor challenge.
Hi, Marla! Thank you for doing this research and sharing your findings. Often times I buy pre-cut onions at the store to avoid the tears. I am looking forward to trying these methods and will be picking up a pare of the goggles (I didn’t know there was such a thing!), I also want to try putting one in the freezer. Thanks again for sharing!
It’s great to hear that you will be trying out some of my tips. I’d love to hear about what works best for you.
I needed this yesterday! I only chopped half of a very small specimen and I barely got through it. I am SO sensitive to the smells and I love cooking with them. I think goggles must be what I need, I’ve tried several other techniques without luck. I haven’t tried the freezer/refrigerator trick though, I will have to try that while I wait for my onion goggles!
Now you have some tips for the next time you chop up a batch. Once you find what works well for you, you’ll be tear free!
Love the tips here! I used to always joke with my mom that I needed protective gear to cut onions. How funny that there are actually goggles purposely made for the job! I think I’ll be trying a few of these other ideas before investing in a pair, though. I’ll be putting mine in the fridge from now on.
It’s so nice to hear that you are ready to start trying some of these tips. I’m sure that with a little experimentation, you’ll find the tear relief you’re looking for. If you opt for the goggles, just think of the fashion statement you’ll be making, ha-ha.
I’ve only heard about those goggles but not about the other things. Apparently you learn something new every day, haha! That refrigerator tip sounds something that could work in my case – my eyes are really sensitive and even when I’d try to look away from the onion my eyes start to water. Those goggles did work but I rarely even remember where mine are! The only downside with that handy fridge tip is that you easily can forget to put that onion in the fridge, which in the end doesn’t help at all.
Thanks for the tips! They’re really useful for the future.
Yay! Someone who has tried the goggles successfully. As far as finding them goes, one idea may be to keep them near where you store your onions. Hope it helps.
Best thing I ever found was to chew gum while I cut them, but for the most part I just cut ’em and get it over with. The bigger issue I have with onions is the smell it leaves on your hands for hours afterwards. I found if you rub your hand down with aluminum, it kills the smell. Turns out, they even sell aluminum bars shaped like soap just for that purpose.
I’ve heard about chewing gum while cutting onions. I just can’t figure out how that protects my eyes. Stainless steel (not really aluminum) bars of all types are available on Amazon and yes, they do work. Use it while running your hands under water to get the best results, then just suds up and rinse off. You should be good to go.
For real? Goggles!!! Hilarious! But has anyone noticed after those teary eyes, your eyes become clearer? The points above will be very useful when cutting a large quantity,
Someone once told me to chew gum while cutting onions and I would not have watery eyes but I always forget. I will try all the points listed and see which one works for me. Great article though and very helpful.
Thank you for your nice comments! I’d like to know what tips worked best for you.
Wow, Marla. Thanks for sharing this! I always wondered about the science behind why an onion makes you cry because all of the little tips and tricks sound crazy when you don’t have any context; and I am a person that thrives on knowing the method to the madness. I also think that knowing the science behind things helps you to sift through the bogus tips. I am definitely not incredibly coordinated in the kitchen, but I’m beginning to learn, SLOWLY. ;p Thanks for the tips! I will definitely be trying out the freezing tip and the overhead fan tip, the next time I’m chopping onions!
I’m delighted to share the explanation of what makes us cry when we’re chopping up these beasts. I agree that it does help to know the “whys” behind cooking challenges before you start trying out new techniques. Enjoy experimenting!
This is a great article. Reminds me of my days of cooking in the kitchen in THAT restaurant. There was a well seasoned salad lady. She was just remarkable, but loud! Anyway, one of her jobs was cutting and prepping veggies for the cooks to prepare. So she cut onions on a daily basis. Her trick? Put a small table fan on the counter before her as she peeled, shredded, chopped, sliced pounds and pounds of them. The downside? The poor unfortunate soul passing behind her…
One real tip I find is to rub lemon juice over your knife. This doesnt work for some, but i’ve found that it worked for me.
Cheers all.
Your story was so enjoyable. It brought back memories of the first kitchen I worked in. The exec. chef was this big Samoan who would cry like a baby as he cut up a batch. His solution–give them to me, yikes!
This is GREAT!
All the times I have started cutting an onion and started at the root end, now I feel completely silly. I was just mentioning this to my girlfriend and she started laughing at me because apparently she knew this.
In our house we always have a small challenge going about who has to cut them up (seems like they are in every single meal we cook) and who is going to cry the most. She cuts faster than I do, so she always wins. Now I’m going to take a few of these secretly and see how it goes tonight. I’m going to put one in the freezer right now and see how that goes.
As I read your post, I had to laugh and wonder if your knife skills are selectively slower for onions. Just joking, but I’m happy to hear that you have a plan of attack.
My trick I learned from my dad who had a restaurant is to cut the onion in half, and then rinse or soak the it in hot or warm water. It reduces any tears, and does work. You can cut off the root and then rinse under water to wash away the acid. Different ways work for others, but I find this is the quickest way.
Nice tip. I wonder if the soaking may have some effect on the texture. Looks like I may need to try it and see.
Those goggles seem a really cool idea. I always peel mine and place it in a bowl of cold water. I prepare my other meat or vegetables and pick the onion last. They never make me cry. Placing them for a while in cold water works wonders. Just try it out.
I think the freezer trick would also work!
Your idea sounds like a good one. Allowing them to chill while preparing your remaining ingredients should do the trick.
My eyes are so sensitive. I doubt most tricks would work on me. I’ve even had my eyes burn up from cutting strong green onions and leeks that had been in the fridge, so I that tip is a bust. Cutting them under the stove while the vent is running might be a good one to try to mitigate the sting. Goggles are probably my best option to really protect my eyes, though.
We all have different levels of sensitivity and yours sounds pretty extreme, sorry. In this case, fully protecting your eyes with a pare of goggles should work well. Give it a try.
Well, you’re a brave woman for trying this out and reporting on your findings! I don’t know if I could handle it!
I hate cutting onions – it stings so bad that I sometimes start jumping around in pain. On a few occasions in the past when I had to cut a lot of them, I would put on a scuba diving mask… I was subjected to many laughs, but hey it worked! It’s not stupid if it works, right?!
On another note, someone once told me to hold a big piece of bread with my mouth so it sort of filters and absorbs the gasses as I breathe through my nose. I haven’t tried it yet, but it might be just ridiculous enough to work. What do you think?
Hey, a scuba diving mask that works beats doing the kitchen onion dance any time. I’ve heard of the bread idea, but hesitate because it is not what your breathing that causes pain, it is what your eyes are exposed to. Besides, I don’t think I could keep myself from just eating the bread, uh oh.
I’m definitely going to put mine in the freezer for awhile before I start chopping it for dinner tonight. I hate when my eyes start streaming while I’m putting dinner together…by the time everything is prepped my mascara has run halfway down my face! 😉 I’ve tried wearing my glasses while dicing them before but it’s never really made much difference so I kind of just resigned myself to tearing up the whole time…it’s cool to know some of the science behind what makes that happen and how to mitigate it 🙂
Let me know how chilling trick worked out for you. I think the problem with regular glasses is that they don’t seal around your eyes and allow exposure, therefore tears. You might want to try goggles.
Thank you Marla! – This article is really helpful, as I always end up with mascara half way down my face when I chop some. I have just tried putting them in the freezer before I slice them and it works, I will definitely be telling my friends this tip. I might also buy my mum a set of those goggles for mother’s day as it will make her laugh! Thank you for the useful tips.
How great that you found a helpful tip and that you can now keep your mascara where it belongs too. Don’t forget you can share the entire article with your friends if you’d like.
I use the fan vent over the stove and also put the cutting board (on the counter) abutting the stove and turn the flame on low to medium— the fire definitely helps burn off the tear-gas! Only problem is when the stove is full of other things, a flame with a pot on it doesn’t seem to do the trick. Rinsing under cold water helps a little but I find makes it a little slipperier to work with, so not a great idea. I’m excited to try the freezer trick and add that to my bag! I think my glasses help a little but I’ll try goggles over them too! I always tear so badly that I can barely see what i’m cutting, which is why I use an onion slice holder to go faster without catching a finger 🙂
This is so helpful!!
Personally, I love onions. Most of my friends think I’m crazy.
The problem is I REALLY hate cutting them. I’m definitely going to try those goggles, I didn’t know they existed
Now you should post a lot of recipes using the ton of onions you bought to try all these methods.
Also “here is where we get to the root of the problem”. I’ll have to admit that I laughed a lot louder than I should.
Being passionate about food is something I can definitely relate to. I encourage you to try various methods to make your prep. easier. And thanks for your enjoyable message!
I also have a few tips. After searching the web a lot and asking friends and family I recommend either chewing gum (something in the spearmint helps I presume), or keeping a bit of bread in your mouth, halfway out. I guess it acts like some sort of sponge and traps anything that’s trying to get into your eye and make you cry. You could also try cutting them underwater, if you have like a huge sink or something of the sorts. In the end I guess onion goggles are the best choice, but you could also try my tips for a cheaper alternative.
I HAVE A WINNER!!! Just breathe through your mouth and not your nose when you cut those little things 😉 trust me on this one. Your nose has alot to do with the eyes. Thanks for the article, it was very fun to read.
Thanks for all the suggestions!. One weird one that I heard as well was to hold a piece of bread in your mouth as you cut, but I prefer the freezer option better. Great tips!
I love onions (especially raw) however sometimes eating them causes a nasty headache.
About cutting&crying: I didn’t know there’s sulphuric acid involved! :O I never cut the root part but throw it away and use the outer layers only. No need to use those silly swimming goggles.
My flatmate has contact lenses and says the chopping onions does nothing to her.
It’s nice because she doesn’t mind preparing them and I am not gonna cry for an hour after it 🙂
So, maybe ask you friends and family with contact lenses.
Yes, I find that when I’m wearing my contact lenses, cutting onions or shallots doesn’t bother me. Unfortunately, I don’t always wear them and I cry my eyes out!
This is a good science lesson 🙂
When I chop up a batch, I keep some water in my mouth and it does the trick. But now, since I’ve read what causes the crying, I am wondering why does it work. Well, it’s similar to the gum chewing tip and maybe it has something to do with keeping out taste buds “busy”.
Did you also tried chewing gum while chopping that big amount of onions?
This is exactly what i was looking for! I’ve shed so many tears over this vegetable and it can get messy because I wear prescription glasses and I have to stop several times during the cutting process to clean them. This post is a lifesaver, I’ve tried to wash them with cold water or putting them in a bowl with water but it doesn’t work for me. I will make sure to follow your suggestions, I will try out all the different methods to find out which one works best for me. Thank you!
I hate cutting onions. I have always been more than sensitive to them. It gets downright painful for me. Anything to mitigate this has my attention. Thanks for the article. I think it’s going to make my life a bit easier.
Oh my gosh, I didn’t know they created sulfuric acid! No wonder it burns so bad, definitely not a normal cry. I think I need a sharper knife to cut with, I can’t believe I was making it worse just by having to press down harder with my somewhat dull knife to cut. I enjoy cooking a lot so I cut onions all the time and I dread every second of it, I can’t wait to try putting them in the freezer.
When I was a kid there used to be a tip in a children’s book to use goggles. Never had I ever thought they would actually make onion cutting glasses, haha! 7-year-old me would be amazed by the fact. I never knew that it was a real deal until now – but the other tips are way better than buying expensive classes just to cut onion. Yes, the pain is real, but it hurts you even more to pay a such price for a pair of goggles!
I’ve heard of most of these tips and tried them but they did not work for me at all. I’ve even heard that you should breathe through your mouth and not your nose, tried and failed. I’m certainly trying the freezing tip, and the not cutting into the root tip, the goggles one….I’m just giggling imagining hubby’s face when he walks into the kitchen with me wearing those goggles! He uses similar ones for work, and I don’t think he’ll get why I’m using them. So that one’s out for me as well. 🙂
My method is easy. What I do is ´hand dice´ onions. Take an onion in your left hand. Cut a bunch of horizontal lines in the onion. Then spin the onion 90 degrees and cut another bunch of horizontal lines.. so you are basically making tiny squares with the cuts. Then you move the onion over the bowl and slice it longways, which removes the diced onions. on layer at a time.
How this helps to prevent tearing? because you can do the first two parts under your kitchen faucet. I can actually dice an onion faster in my hand than I can using a cutting board.
The other tip if you can do it.. dice your onions last ( same with jalapeño peppers). It makes it a bit less miserable to not have to dice or cut other things afterwards.. you can dice the onions last, start the cooking, and then take a few minutes to wash your face and hands.
My husband dices this way too. He taught me this trick. I have seen people cut their hands doing it though, so you do have to be careful.
I never thought of doing it under the faucet, but that might help. I did notice a difference when cutting cold instead of at room temperature, so thanks, Marla.
Nothing seems to completely get rid of the effects, but every little bit does help!
This is one of the main reasons why I hate cutting onions, I never really learned how and my eyes ended up all teary after it, so the only method that I know is to kind of close your eyes and pray for the best. But I think that I might want to try the freezer method, it seems such a simple solutions for a deadly torture, lol!
Surprisingly, I also have heard about the onion glasses before, it seemed kind of exaggerated for me to be honest, but I can’t really imagine how chefs are suffering because of the power of onions, those glasses should be available as a regular cooking artifact.
Thanks for sharing these tips with us! 🙂
I didn’t know that about putting the onions in the freezer. Thanks for this article. I can already foresee a lot less tears in my future. I thought the one tip about goggles was a bit funny though. I just tried to picture my husband in the kitchen trying to make himself a sandwich wearing those goggles…
Keep your mouth shut. No talking and don’t lick your lips. Mouth must be totally closed. Try it before you think it won’t work.
bruh but like how do u stop onion from hurting/burning ur eyes if someone else is cutting onions in the kitchen??
Turning on a fan, opening a window, and only cutting chilled onions with a sharp knife are tactics that will help others in the kitchen as well. Otherwise, leaving the room for a moment while others are cutting onions may be your best option.