What is it about preparing onions that brings tears to our eyes?
It can hurt and sting so much when we’re chopping up onions to make Mom’s world-famous meatloaf, or making mirepoix for our favorite soup recipe.
And while we might shed a tear as we’re eating dinner – because it’s that heavenly of a comforting, made-from-scratch meal – we don’t want to deal with a huge cry-fest in the middle of getting prep work done quickly and efficiently.
Do you suffer from the same onion-cutting misery? This is finally your opportunity to stop the tearful madness!
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If you are determined to know the reasons for this unfortunate occurrence, as well as how to combat them in your own kitchen, dry those tears and continue reading.
We’ll offer a quick explanation of the chemistry involved in the process, as well as our top five tips for prepping onions without crying.
Pretty soon, you won’t be bawling your eyes out like it’s the sloppy, gut-wrenching breakup scene in your favorite rom-com movie.
It’s not you… it’s the onion!
5 Ways to Stop Onion-Cutting Misery
Crying over Chemistry
According to a 2021 article in Everyday Mysteries, an online compilation of fun science facts from the Library of Congress, a sulfuric irritant called syn-Propanethial S-oxide is the main reason why you start shedding tears as you cut, slice, and dice your go-to allium.
When you first cut into an onion and damage its cellular structure, many volatile molecules escape and are released into the air, including an enzyme called the lachrymatory-factor synthase.
This enzyme acts as a catalyst that converts sulfoxide amino acids into sulfenic acid. Because of how unstable and reactive these molecules are, they then chemically rearrange themselves into syn-Propanethial S-oxides as they continue to react to the molecules present in the surrounding air.
Once these sulfuric irritants come into contact with your face, the lachrymal glands in your eyes become stimulated by the burning sensation and start producing tears.
As you repeatedly cut into the onion, more enzymes continue to be released into the air – causing you to tear up more and more!
You’ll notice this reaction more often with red, white, and yellow onions as well as shallots, which all contain stronger sulfuric compounds compared to sweet onions or scallions.
How to Stop the Tears
There are ways to fight the crying, and the solutions are all quite simple. Take a look at our top five methods to steer clear of the tears:
1. Chill Out
You’ll notice a significantly reduced – or even completely eliminated – reaction when you cut a cold onion rather than one at room temperature.
Placing your onion in the freezer or refrigerator prior to cutting it subdues and slows the irritating power of its volatile compounds, reducing their energy to launch into the air.
Place your produce in the refrigerator for 30 to 60 minutes before you need to start prepping.
If you’re in a hurry, place it in the freezer for a quick 10 to 20 minutes prior to cutting. You don’t want to actually freeze it, but simply chill it.
Similarly, you can completely submerge it in a bowl of cold water with ice cubes for 30 to 60 minutes in order to fully chill it.
2. Turn On Your Stovetop Ventilation System
The ventilation system above your stovetop may help to quickly draw airborne irritants from the veggie into the vents, redirecting them away from your eyes.
But in order for this method to work successfully, you will need to set up your prep station directly under the ventilation system.
Without turning on your stovetop, and ensuring it is completely cool first to prevent any hazards or injuries, place your cutting board over your stovetop and turn on your ventilation system before you start slicing and dicing.
We suggest purchasing and assembling a stovetop cover for a safe, secure, and easy-to-clean base to place your cutting board. With a stovetop cover, you’ll be able to prep on the majority of both electric gas stovetop ranges.
The Gashell Noodle Board Stovetop Cover is compatible with most stovetop ranges, providing a flat and sturdy surface for your prep needs while protecting one of your most cherished appliances.
It has two handles for easy maneuverability, and measures 29.5 inches in width and 22 inches in length.
3. Always Cut with a Sharp Knife
One of the most important pieces of advice to prevent those tears from flowing down your face is to cut with a sharp knife.
It’s worth investing in a good knife sharpener and honing steel to maintain a sharp edge on your blade. An absolute necessity in any kitchen, sharp knives make all of your prep work safer, quicker, and easier!
When you cut with a sharp, well-maintained knife, you can swiftly and neatly cut through the cellular structure of the vegetable, releasing as few volatile compounds as possible.
On the other hand, if you use a blunt blade, there is now a greater risk of mangling the cellular structure as you shoddily cut through the onion, which then causes more compounds to be released into the air.
4. Don’t Cut Off the Root End
And here is where we get to the “root” of the problem!
The National Onion Association, an organization representing growers, shippers, brokers, and commercial representatives of the United States onion industry, suggested in a 2015 article to leave the majority of the root end attached to the main bulb.
The Association explained that the root end of the onion has the highest concentration of sulfuric compounds.
Leaving the root end untouched not only reduces the tears, it also keeps the bulb’s layers intact as you are cutting it.
Review our guide on how to prep an onion, so you can get all the best tips to cut with skill and agility.
5. Wear Onion Goggles
Oh, yes. There is such a thing. And this isn’t a joke.
If all other suggestions have miserably failed you, onion goggles might ultimately be your final option!
These eye-saving gadgets prevent noxious fumes and gas from irritating you, with a comfortable foam seal around the interior rim of the glasses to protect your sensitive eyes.
RSVP International Onion Goggles, available from Sur La Table
We recommend these goggles from RSVP International, which you can purchase with a black/green trim from Sur La Table or Amazon. For other color options, Amazon also sells the same goggles with a pink/white trim, red/black trim, tortoise trim, and white/green trim.
Leave the embarrassment behind you, and purchase a pair soon.
Sure, your family and friends might poke fun at you – but you’ll at least be tear-free from the onions, if not from the malicious bullying.
And there’s now a pile of perfectly prepped produce awaiting to be used in your recipes.
Who’s laughing now?
Learn from Personal Experience
Sometimes the best cooking tips come from scientists, food media websites, and associations, while other times you’ll get some fine advice from your family, friends, neighbors, and even talkative acquaintances at your local bar.
But the real test of a tried-and-true method come from your own constant experimentation in the kitchen.
You won’t know until you try it – you’ll be able to eliminate the failures that didn’t work, and repeat the successes that did.
So go forth without the fear of tears, and try each of our methods we recommended here.
We hope you’ll be able to prep your produce without any teary-eyed side effects, so you can fully enjoy the experience of cooking, from the very first cut to the very last bite.
We can’t wait to hear all about your very own unique cutting tips, and if you tried one of our suggested pieces of advice. Be sure to share in the comments below.
Browned and caramelized, battered and fried, stuffed, baked into pastries… how will you enjoy your onions, now that you prepped them? Review all of our big and bold onion recipes, or try these three first:
About Nikki Cervone
Nikki Cervone is an ACS Certified Cheese Professional and cheesemonger living in Pittsburgh. Nikki holds an AAS in baking/pastry from Westmoreland County Community College, a BA in Communications from Duquesne University, and an MLA in Gastronomy from Boston University. When she's not nibbling on her favorite cheeses or testing a batch of cupcakes, Nikki enjoys a healthy dose of yoga, wine, hiking, singing in the shower, and chocolate. Lots of chocolate.