How To Cut An Onion Without Crying
- Chill the onions before cutting.
- Use a sharp knife.
- Cut the onion properly.
- Keep the exposed cuts away from you.
- Turn on the exhaust fan.
1. Why Do Onions Make Us Cry?
There’s no shortage of things in the world that can make us cry. Global catastrophes. The rapidly mounting rise in inequality. The music of certain pop stars. Our quickly accelerating descent into oblivion. So why should we be content with crying in the kitchen as well?
It’s true: if you’ve ever chopped onions (and chances are that you have), it’s very likely that you’ve found yourself welling up with tears. It’s also likely that you’ve already normalized this to the point where you don’t even ask yourself why this even happens in the first place. Well, let’s break it down, and then talk about how you can avoid it.
So what is it about onions that makes us cry? It all comes down to biochemistry. You see, when you cut, crush, or damage an onion, you kick off a process of “self-defense” for the onion. It’s true! Nature, in its infinite wisdom, has effectively booby-trapped its vegetables so we stay out of their way. And because we are extremely stubborn creatures, we persevere.
When the cell walls of an onion are damaged, a naturally occurring enzyme called allinase interacts with another molecule, sulfenic acid. This chemical reaction creates something called a volatile lachrymatory factor, or “LF.” This is meant to burn the eyes of the predator and keep them away from the vegetable. In our case, it triggers our lachrymal gland. Pretty clever.
So are we hurting ourselves by eating onions? Are we permanently damaging our eyes just for some sliced onion? Nah -- this sulfur compound is only a slight irritant, and won’t cause any long-lasting damage. What it is, though, is somewhat annoying, and sometimes a little embarrassing.
So what can we do?
2. Things You Can Do To Prepare
Thankfully, humans are at least somewhat more clever than the average onion, so we’ve devised a number of precautions to keep our eyes from getting burned by these delicious vegetables. Be warned, though -- there’s also a lot of misinformation out there. We’ll talk about the myths surrounding onion cutting a little later in this article.
To avoid the waterworks, you should:
Chill the onion. This may feel weird, but a cold onion means less propanethial S-oxide will evaporate, which means fewer tears. Remember, though, you’re refrigerating these onions, not freezing them. A chilled onion is great for cutting or dicing an onion, but a frozen raw onion will become mushy after it thaws. Nobody likes mushy onions.
- Use a sharp knife. This is extremely important, not just for onion-cutting but for any kitchen task that involves a knife. A sharp knife is much better than a blunt knife since you’re much less likely to over-exert it and lead to accidents. When it comes to onions, you’ll find that a sharp knife will cause less damage to the cell walls, resulting in fewer irritants released into the air (and your eyeballs)
Cut the onion properly. We’ll get more specific in the next section, but if you want to reduce the amount of the dreaded onion gas, follow the lead of professional cooks who follow an efficient and effective way of dicing onions. This will reduce the amount of acid enzymes in the air. And this leads to our next point…
Keep the exposed cuts away from you. That’s right: as soon as you cut an onion in half, turn both halves down on your cutting board. Only peel the sides as you continue chopping them, and once you’ve finished one part, move the sliced pieces of onion into a prep bowl away from you. Basically: minimize exposure as much as possible.
Turn on the exhaust fan. This may seem obvious, but you’d be surprised at the amount of people who never made the connection. The vent hood is going to help pull away these irritants and keep them far from your eyes.
Wear goggles. Yes, this may sound silly, but it’s a legit option! There are brands that make especially designed onion goggles for cutting and dicing an onion, which form a tight seal to keep the irritants out of your eyes. It looks ridiculous, but it works. That said, most folks prefer to stay away from this option, and we can’t say we blame them.
3. The Best Way To Cut Onions Without Crying
Once you’ve taken the above precautions, it’s time to actually chop an onion. There are about as many ways to cut onions as there are people in the world, so we’re going to focus on our favorite method of chopping onions. This will speed up your prep and make things easier for you, in addition to giving you a new knife skill.
Step 1: With the root end facing up, cut the onion in half. (Remember to keep the exposed side away from you).
Step 2: Peel off the skin from the end you’re going to cut first. Again, we want to keep exposure to a minimum, so don’t peel the other end until you’re ready to move on to it.
Step 3: Lay the first half cut side down with the non-root end facing you, then make your cuts vertically through the onion. Be careful not to cut through the root.
Step 4: Turn the onion so that the root end moves to the left, and the non-root end is on the right (if you’re right handed; otherwise, it’s the other way around). Now with your knife parallel to the onion, make three horizontal cuts through it: one near the bottom, one in the middle, and one near the top. Again, be careful not to cut through the root.
Step 5: Now simply chop your onion with cuts running perpendicular to your first vertical cuts. You’ll end up with perfect little squares that you can use in all types of dishes.
4. Best Knives For Cutting Onions
In order to slice, chop, or otherwise cut those onions without looking like you’ve just rewatched the first ten minutes of Up, you’re going to need the right tools for the job. Below, our selection of best knives for cutting onions.
Let’s start things off with a classic. This 8” Chef’s knife from Dalstrong’s acclaimed Gladiator Series is your multi-purpose kitchen powerhouse, helping you not just cut through all manner of vegetables but accomplish all manner of kitchen tasks.
- A formidable tool: precision forged, ultra sharp, single-piece, high carbon German ThyssenKrupp Steel at 56+ Rockwell.
- Extremely sharp, hand sharpened to 16-18° per side.
- A sturdy, well-constructed full-tang knife that will last you a lifetime.
- Ergonomic, military-grade G10 handle; feels great, looks great.
- This elegant and understated design might not be the choice for home cooks who are looking for some showy pizazz on their magnetic knife holder.
- This is an 8-inch Chef’s knife, so it’s likely that you already have a knife this size in your kitchen (but still, it’s worth an upgrade); if you’re looking for something that’s especially designed for fine cuts of vegetables, maybe a paring knife is the choice for you.
Sleek, powerful, and well-proportioned, this 4” paring knife from Dalstrong’s Quantum 1 Series is everything you need to perform all manner of fine cuts on your fruits and vegetables.
- Made of ultra sharp, wear resistant, single-piece, high carbon American BD1N-VX steel.
- Gorgeous look, conveying stealthiness, agility, and forward motion.
- Features a fiber-resin military grade G10 & Carbon Fibre Hybrid handle, which is nearly impervious to heat, cold and moisture.
- Features a tapered design for hardness and flexibility.
- If you’re looking for a larger knife, check out some of the other selections in this list.
- It’s a bit on the hefty side for a paring knife.
A utility knife is your go-to kitchen workhorse, and a serrated utility knife is even better when it comes to grabbing on to food and ruthlessly tearing away at it. Not only that, but as part of the Shogun Series, this knife is absolutely beautiful.
- Made of a precision forged blade with an ultra-premium Japanese AUS-10V ‘super steel’ cutting core.
- 67 layers of high-carbon stainless steel cladding.
- Features a magnificent hand-polished visual pattern, the Dalstrong “Tsunami Rose” design. It’ll get people talking.
- Ultra-premium G-10 Garolite handle, which looks and feels great.
- Serrated knives are usually a bit trickier to sharpen than straight blades.
- You’ll find this a great tool for working with vegetables, but the serrations might result in more irritants in the air than some of these other knives.
This gorgeous 7-inch Nakiri vegetable knife will help keep onions from making you cry, but it might bring tears to your eyes with its incredible performance and looks.
- Nakiris are especially designed for handling vegetables, so you’ll feel extremely natural and comfortable as you chop away with this knife.
- A high-quality blade, made of high carbon American BD1N-VX steel at an astounding 63+ HRC.
- The blade features a beautiful hand-polished satin finish.
- Comes with a beautiful leather carbon-fiber sheath. A great gift for your favorite cooking enthusiast.
- Nakiri knives are a bit lighter than most Western types of knives, so keep that in mind.
- Nakiri knives are fantastic for cutting fruits and vegetables, but they’re not as versatile as other types of knives. If you’re looking for versatility, check out the 7-inch Santoku knife below.
This is an absolutely gorgeous and uniquely powerful Santoku 7-inch knife that will aid you in all manner of kitchen tasks, not to mention giving these onions a good what-for. Form, function, and dazzling looks -- you can’t go wrong with a tool like this.
- Painstakingly hand-sharpened by expert bladesmiths to 8-12° per side. Extremely sharp and extremely resilient.
- Made of extra-durable, ultra-sharp BD1N-VX steel.
- Gorgeous appearance, sporting the Nova Prime blade pattern which not only looks good but helps reduce drag on your food.
- Beautiful and comfortable Dragon Skin G10-carbon fiber handle.
- This premium product is toward the top of the price range represented in this list.
- Santoku knives are generally more lightweight, so if you’re looking for heft, you’d be better served by some of these other options.
5. Stop The Lies: Destroying Myths About Cutting Onions
Some of you may be staring at this article and thinking “now, hold on a minute… why haven’t they talked about this obscure solution I heard from my grandma?” There’s a lot of information out there, and not all of it is accurate. When it comes to cutting onions, a problem that has plagued humanity since time immemorial, there’s an incredible amount of misinformation out there.
Now that you know how to avoid getting tears on your cutting board, let’s talk about the different myths that have been perpetuated through the years, and finally set the record straight. Here’s a list of prevailing myths about how to avoid tears while you chop an onion, and why they don’t work.
Myth #1: Using a wooden cutting board instead of a synthetic one, or vice versa. You may have reason to use one or the other -- us, we’re partial to a stylish teak wood cutting board with satin-finished steel handles -- but it makes no difference as far as avoiding tears in the kitchen.
Myth #2: Holding a piece of bread in your mouth. We’re not kidding, this is actually real advice that has been passed down through generations. How is it supposed to work? What’s the logic behind it? Who told people that holding a piece of bread in your mouth is somehow going to help? It’s a complete mystery to us. As much as we love bread, this does not work.
Myth #3: Microwaving onions before cutting them. The idea here is you nuke the onions before you actually cut into them, causing the microwave’s to weaken the harmful acid in the onion. Does it actually work? If what you’re trying to do is stink up your workplace lunchroom, absolutely. Otherwise no, this won’t help you.
Myth #4: Putting a candle beside the cutting board. This tip is credited to Martha Stewart, so we’re heartbroken to be put in a position where we have to debunk her. Alas, dicing onions by candlelight may be extremely romantic, but it’s not going to draw in and burn off the LF before it gets to your eyes. Sorry, Martha.
Myth #5: Cutting off the base of the onion and disposing of it. Here’s one that sounds plausible when you first hear it, but doesn’t really hold up in practice. Supposedly, the base of the onion is where most of the enzymes and molecules are concentrated, and by getting rid of it you’ll eliminate (or reduce) the irritation. Nope, doesn’t work.
Myth #6: Breathing through your mouth while chopping onions. Alternatively, chewing gum while you chop onions. The idea is that breathing in through your mouth will draw in the sulfur before it hits your eyes. If you’re raising an eyebrow now and thinking “that doesn’t really make sense,” congratulations. The only thing this is going to help you with is perfecting your Darth Vader impersonation.
Myth #7: Cutting onions under running water. Some specify that it should be cold water. Okay, this one does have some merit. The idea is that the running water will wash off some of the sulphuric compounds… and what do you know, it seems to work somewhat. Results will be mixed, and this isn’t a very convenient solution, not to mention its a little dangerous, so we’re giving it a failing grade.
6. Frequently Asked Questions About Onions
What is the best way to store onions?
Well, the very best way to increase the shelf life of onions is to store them whole. Put them in a cool, dark, well-ventilated place, between 40-50F. If you expose them to too much moisture and light, they’ll start to sprout and rot. You don’t want that!
You might find you’re tempted to store them in a plastic bag, but this is a bad idea. The lack of air movement will reduce their storage life. What you could do is wrap each onion in paper towels or newspaper, and then place them in the refrigerator, keeping them cool and dry.
After I cut or use part of an onion, how long will it keep?
If you’ve already taken the leap and want to salvage what’s left of our oniony friends to include in more recipes down the line, don’t panic! Chopped or sliced onions can be stored in a sealed container in your fridge, and the USDA says they’ll last between 7 and 10 days (provided that they’re kept at the proper temperature of 40F or below).
How do I get rid of the smell of onions from my hands and cooking equipment?
You don’t. The smell is part of you now. This is just who you are from this point forward, and how you’ll be known for the rest of your life -- “the onion guy.”
No, we’re kidding. It might seem hard to do at first, but getting rid of that very identifiable onion smell is much easier than you think. All you have to do is rub your hands, or your cooking equipment, with lemon juice. You’ll find it’ll quickly fade, leaving you with a fresh and lemony smell (which you can just wash off with water and soap if you’re not looking to smell like a lemon either).
Are onions healthy?
You bet! Onions are fat free and low in calories in addition to being absolutely delicious in many presentations. Also, they are a great source of fiber and high in vitamin C. Any way you slice it, onions are a wonder, and we’re extremely lucky to have such a useful and versatile vegetable at our disposal. Even if it’s always trying to make us cry.
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Written by Jorge Farah
Born on the coast of Colombia and based in Buenos Aires, Jorge is a cooking enthusiast and kitchenware obsessive with a tremendous amount of opinions.