Ever wondered why some recipes call for a particular kind of onion and whether another can be substituted in its place? We certainly have.
All these onions vary slightly in flavor, texture, and color, but can usually be substituted for one another. In terms of cooking, they will all behave the same in the pan.
When buying onions, go for ones that feel heavy in your hand and firm. Avoid soft onions or ones that have a sharp oniony odor before peeling. These are indications that the onion is old. Except for sweet onions, all these onions can be stored for several weeks in a cool, dark pantry or cupboard.
Yellow Onions - We consider this the all-purpose onion, and personally, it's the one we use most often. Yellow onions have a nice balance of astringency and sweet in their flavor, becoming sweeter the longer they cook. They are usually fist-sized with fairly a fairly tough outer skin and meaty layers. Spanish onions are a particular kind of yellow onion and we find them to be slightly sweeter and more delicate in flavor.
White Onions - These onions tend to have a sharper and more pungent flavor than yellow onions. They also tend to be more tender and have a thinner, more papery skin. They can be cooked just like yellow onions, but we also like them minced and added to raw salsas and chutneys.
Sweet Onions - Walla Walla and Vidalia are the most common kinds of sweet onions. These onions lack the sharp, astringent taste of other onions and really do taste sweet. They are fantastic thinly sliced and served in salads or on top of sandwiches. They can range in color from white to yellow and often have a flattened or squashed appearance. Sweet onions tend to be more perishable and should be store in the refrigerator.
Red Onions - With their deep purple outer skin and reddish flesh, these are really the odd-guys out in the onion family. They are fairly similar to yellow onions in flavor, though their layers are slightly less tender and meaty. Red onions are most often used in salads, salsas, and other raw preparations for their color and relatively mild flavor. The lovely red color becomes washed out during cooking. If you find their flavor to astringent for eating raw, try soaking them in water before serving.
Do you have a favorite kind of onion?
Related: Leeks, Shallots, and Onions: Savory Allium Recipe Round-Up
(Image: Flickr member masonmasteka licensed under Creative Commons)
(Originally published October 21, 2010)
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In the white onion's section...I think you meant to say they can be cooked like the yellow onion instead of the white onion.
Great article!
Ah, yes - thanks!
I'm not usually an onion fan, but I do love red onions!
They seem to have a "fresher", gentler flavor. I like them both raw & cooked.
Red onions are also good thinly sliced and lightly salted before eating raw...makes them a little more mellow.
If you make Mexican food and have been using yellow onions, get white onions instead. The flavor is so much milder and cleaner, and if you're concerned about authenticity, they just taste right. I never substitute yellow for white now I've learned that. Chopped and rinsed, you can use them as a sweet crunchy raw garnish where yellow onions would be waaay too strong.
(Jeez, I sound like a white-onion broker. I'm not! I just recommend keeping one on hand, that's all!)
You know, this finally made me try and look up something- my favorite onions to cook with are actual green onions and only one grocery store near me all year long sells what they call "barbecue onions" and all they seem to be are a bunch of green onions left in the ground til the white shoot bulbs out into a small onion. I haven't be able to find any info on them (especially not about barbecuing!) and I've never found them elsewhere. I get them from time to time and use them as I would regular green onions. They taste the same, if not milder.
Anybody familiar with these guys?
I rarely use raw onions (not a fan), but when I do it's usually red onions in a salad. I like to lightly pickle them first--in red wine vinegar, water, salt, and sugar--which brings out their sweetness and mellows them considerably.
I've always used yellow onions whenever I cooked, but recently I tried out white ones instead and I think I like them better! Red are the only ones I'll eat raw. The others are too strong for me unless they are cooked.
It must just be me, but I've always found red onions to be the sharpest, and white to be the most mild. I don't mind red, but prefer them to be heavily cooked, where white seem to be ok cooked or not. I guess I'm just weird like that.
@jmorri26 - I love green onions, too! I'll take 'em straight-ended like leeks, or bulb-ended (usually called "scallions) then, but I've seen them with larger bulbs. I think they're usually called "spring onions" then. They're basically just young onions. My favorite way to use green onions is to make green onion and potato soup:
a bunch of red potatoes, cubed
1-2 bunches green onions, white and most of the green part sliced
water not quite to cover
1/4-1/2 cup cream cheese
milk
Cook the potatoes and green onions in the water until soft. DO NOT DRAIN. Mash potatoes in the water (a flat whisk works very well for this) until mostly smooth. Add milk and cream cheese. Add more or less milk to reach desired consistency. Salt & pepper to taste.
Perfect on a cold, rainy day like today. :)
Oh white onions, why did I fear you for so long? What ingrained bias made me believe, without trying for myself, that Walla-Wallas or anything with a colored skin was inherently better? I only just started using white onions a few months ago. Maybe it's because they glide right through my mandoline, or maybe it's because they really do taste better. For whatever reason, I am always much happier when I find that there are still white onions in the fruit bowl. Those reds have been sitting in the fridge for a long, long time now.
You can keep red onions from losing their color by adding a splash of vinegar. They look great caramelized this way.
@jmorri26 and vintagejenta — Scallions and green onions are actually the same thing. The green onions with little bulbs on them are spring onions. Something that might also look similar are ramps, but ramps have a more garlicky flavor.
@jmorri26 - would these be knob onions? (at least that's what I see them referred to in my local mexican market)
they do look just like green onions/scallions, except the white part is about the size of a golf ball. anyone?
"Barbeque" onions are exactly that. Great on the grill, until lightly charred in spots. Wonderful side to any grilled meat. I first had them on the Pacific Coast of Mexico.
I love every kind of onion... especially red. I put them in just about everything I cook... even if it doesn't call for onions. They make everything better!
love onions and use in alomost everyting I make!) in my pantry and most asian homes you will find scallions and shallots (The shallot is a relative of the onion, and tastes a bit like an onion, but has a sweeter, milder, yet richer and more complex flavour.)
I love onions and cook with them on a daily basis. Peppers and onions are staples in my kitchen. I use yellow mostly and red on occasion.
http://casa-giardino.blogspot.com/2010/08/cipollata.html
In this house it is whatever works for the dish.
Red onions are for toasted veggie sandwiches, tuna salad and in pepper frys.
White onion in chili.
Sweet when in the mood for a change.
Green onion for salads.
Yellow for Turkish lentil soup and risotto.
I'm with Joe Enos - red onions are my least favorite, too hot.
My CSA gives us these flattened onions, they resemble those "donut peaches". You carve out the tops, put a little butter in the indentation and roast - they are like candy.
One other way I love onions is those little pearl ones, in beef stroganoff or with green peas. I don't know whether they're just baby onions or their own thing.
I use them all interchangeably.
Try thinly sliced red onions, soaked in lime/ lemon juice for half an hour or so. They take on a beautiful pink, and a vinegary tang... Add thm to salads..yummm
Thanks for the breakdown. Very helpful as I usually only keep yellow onions on hand and maybe a few Vidalias when in season.
I get all "really? I have to go buy one?" when recipes specify red or white and often just sub in a yellow (although I never feel that way when it's scallions or cippolini, I just happily trot out and pick some up). But now I can proceed better informed!
Joe and tasterspoon--I'm with ya. I'm surprised to hear people finding red onions the mildest. To me, they completely take over the flavor of a dish and that's all I can taste if they're added with more than just the lightest hand. I wonder if it's some sort of hard-wired thing, like cilantro lovers/haters.
walla wallas and vidalias, cooked on a charcoal grill... mmm... works with almost anything.
oddly, i rarely (if ever) use plain yellow or white onions, though reds are great for salads to add color and bite.
maybe i'll try some white onions on the grill next time - since vidalia onions aren't in season down here anymore anyway
good post. i use red onions exclusively in the raw state, soaked in water with a little white vinegar to take the edge off.
I love red onion raw and pretty much use yellow onions for all of my cooking. But if I only have red onion on hand and am making a recipe that calls for onions, I don't see any problems with subbing in the red.
I agree with Kat88, above; red onions have a piercing aftertaste that ruins everything else about a dish for me. I can't stand them.
I also very much dislike plain, raw onions of any color or type, except possibly a small bit of sliced scallion as a garnish on certain (primarily Asian) dishes.
But plain old yellow storage onions? I go through them like nobody's business! I suppose I need to revisit white onions, and I have been meaning to work on duplicating the excellent Vidalia onion and Jalapeño pepper salsa I had at a neighborhood party last year.
"I think they're usually called "spring onions" then. They're basically just young onions." " a bunch of green onions left in the ground til the white shoot bulbs out into a small onion." These are spring onions or the larger ones are shallots. They are not young onions, but a variety of their own. Shallots are especially delicious baked. Much sweeter & more flavoursome than other types of onions. Spring onions are wonderful in stirfries, or use the green stem finely sliced for salads.