The Great Caramelized Onions Debate

There’s been a kerfuffle over the past week around the issue of caramelized onions and whether or not they can be made in a short period of time, such as ten or fifteen minutes. (What you missed it?)

It started with this article on, in which Tom Scocca complains that “recipe writers” lie about how long it takes to brown/caramelize onions (he uses the terms interchangeably). That caused a bit of a roar here and there, with some people agreeing with him that it takes at least 40 minutes to caramelize onions, and some disagreeing.

I can’t say I followed the issue very closely, as I’ve always been in the “low and slow” camp; my caramelized onions take anywhere from 45 minutes to an hour, and I have many better things to do with my time than argue something like this. Then Jacob Burton of weighed in, creating a somewhat annoying but quite informative video in which he proves that onions can be “caramelized” in ten minutes.

He raises some very good points about the kind of pan that is used and whatnot. However, I am not convinced. I absolutely do believe that Jacob Burton browned those onions in ten minutes, but that’s not the issue. The issue is one of terminology:

“Browning” and “caramelizing” are not exactly the same thing.

What Burton created was a really nice pan full of browned, fried onions. This is in contrast with what many people (myself included) refer to as “caramelized” onions, which are slow cooked for a long time. The result is something quite different. Fried onions have both a sharp and a mellow flavour, and a strong aroma. (Everyone loves the smell of fried onions!) Caramelized onions–and perhaps I should be specific and say slow caramelized onions–have a much mellower and sweeter flavour and a more low key, almost buttery aroma. The flavour of slow caramelized onions is hardly oniony at all; in some ways it’s more like baked apples in butter. (If you’re really patient, you can go for deep caramelized onions, like these.)

I suspect that back in Julia Childs’ day, few people confused the two. It was clear that fried onions were fried onions and caramelized onions were caramelized onions, the same way we distinguish between roasted meat and braised meat. But few people make the distinction now. I speculate it’s because “caramelized” sounds fancier and “fried” is like a swear word in some circles. With the rise of the “foodies,” and all the half-informed and competitive bombast that came with it, the result is that “caramelized” is now used whenever you apply heat to onions and make them turn colour.

Let’s drill down a bit more: Wikipedia makes a distinction between caramelization and the Maillard reaction. In brief, the Maillard reaction is:

…a form of nonenzymatic browning. It results from a chemical reaction between an amino acid and a reducing sugar, usually requiring heat.

And caramelization is:

… the browning of sugar, a process used extensively in cooking for the resulting nutty flavor and brown color. As the process occurs, volatile chemicals are released, producing the characteristic caramel flavor.

Sounds pretty similar, doesn’t it? The caramelization article goes on:

Like the Maillard reaction, caramelization is a type of non-enzymatic browning. However, unlike the Maillard reaction, caramelization is pyrolysis, as opposed to reaction with amino acids.

Aha! I’m no chemist, but based on the Wikipedia description of pyrolysis:

Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen.

And there, perhaps, lies the difference. Most recipes for slow caramelized onions call for low heat in a covered pan. That’s nowhere near an oxygen free environment, but it’s a lot less oxygen rich than something sizzling in an open pan over high heat with a lot of stirring. (You need to read the whole article to get the full picture, but suffice to say that my recipe for slow caramelized onions uses a very moist environment, exactly what is needed for pyrolysis.)

I won’t go on with the technical stuff because there are plenty of people on Reddit who will gladly dedicated their dying breath to the splitting of such hairs. I’ll leave it to them.

My point is that when you fry onions fast and hot, you get a different plate of food than when you cook them slowly under low heat. Both are good, but they are different. And because they are different, they should have different names.

I propose “fried onions” and “caramelized onions.”

6 thoughts on “The Great Caramelized Onions Debate

  1. Five pounds of onions, sliced along the grain, & 1/2 cup (1 stick) of butter. Into a slow cooker, cook on low overnight.
    Otherwise, same quantity in a Dutch oven, on low over a heat diffuser, for a couple hours.

  2. Didn’t follow the kerfuffle, but I’m amazed people don’t know the difference between fried & caramelized onions. I love fried onions.

  3. So I’m a little confused about this whole thing. I find this conversation fascinating (I can’t explain why), but I do have a few questions.

    I understand the difference between the Maillard Reaction and caramelization. But can you please explain how the browning that occurs over a long period of time is technically different from a browning that occurs over a short period of time? I can’t wrap my mind around distinguishing the two.

    Is the 10 minute version really “Maillard Onions?” At what point do “maillard onions” become caramelized onions? Is it a temperature threshold or a time threshold?

    Aren’t the same sugars or chemicals or whatever caramelizing or browning whether that reaction is occurring fast or slow?

    I’m so confused… :-/

  4. Matt, I can’t really be more specific because, as I said, I’m not a scientist. What I can say is that fried onions and low-slow caramelized onions smell different, taste different, and have a different texture. Exactly what’s happening with the sugars and proteins is more than I can say, but I know there is a difference in the end result.

    For a parallel example, look at what happens to meat when you cook it hot and fast versus low and slow. Hot and fast is good when the cut is naturally tender and you want the meat to to be rare. But if you take a tough cut that has a lot of connective tissue and cook it hot and fast, you end up with something so tough it’s almost inedible.

    But take that tough cut and cook it low and slow and the collagen in the connective tissues eventually turn into gelatin, which is why slow-cooked meat “falls off the bone.” Perhaps there’s something similar happening with the sugars and proteins in onions.

    Some people have made references to very deeply caramelized onions. In my case, my caramelized onions don’t go so deep (you can see a picture here, although usually they go a bit deeper than that).

    I suspect there’s a couple of things going on here. First, maybe my caramelized onions aren’t very “maillardized.” They’re definitely very sweet and not tart or astringent at all. But the color doesn’t get very brown. (Again, the difference between caramelizing and browning.)

    When you fry onions, you get browning (Maillard?) on the outside, but the inside remains “somewhat cooked but not really caramelized.”

    When you cook low and slow for an hour or so, you get little browning, but the caramelization effect is thorough — which is to say the middle of the onion is just as caramelized as the surface.

    When you cook low and slow for a very long time you get full caramelization, PLUS maillard-like browning all the way through.

    At least that’s how I see it.

  5. Thanks for the response. I understand you’re not a food scientist so I really appreciate you taking the time to answer my question to the fullest of your ability.

    I get the difference between tender cuts and tough cuts on an animal being cooked fast versus low and slow. But to my understanding, the slow cooking methods are there to break down the collagen into gelatin and that’s the difference between tough meats and tender meats; tender meat doesn’t contain a bunch of collagen. (I’ve been using my “On Food and Cooking” book as a reference).

    But when it comes to onions, an onion is an onion right? I always thought a caramelized onion was pretty much how it was described in the Slate article, “dark, soft, brown and sweet.”

    Watching that video on the Stella site, the onions do look caramelized when the video timer passes 9 minutes and then overdone (in my not so knowledgeable opinion) when the guy actually puts them on the plate. But the onions definitely look soft and cooked through.

    I guess what I don’t get is, isn’t caramlization the same chemical reaction no matter how long it takes. If you put raw sugar in a pan (or in the case of an onion, fructose, according to McGee) doesn’t it either caramelize or not caramelize depending purely on the temperature of the sugars and not the amount of time it took for the sugars to reach those temperatures. So if the onions sugar caramelize and the onions are cooked long enough to make them soft, aren’t those caramelized onions? Or am I missing something?

    I haven’t tried the 10 minute method yet but assuming that the onions are soft, dark brown and sweet, if you didn’t know they were cooked in 10 minutes wouldn’t they be called caramelized onions? I mean, I get that taking 45-60 minutes could produce a better result, but the debate always seemed to be over whether or not it was possible to “caramelize onions” in 10 minutes (which I guess the word caramelization is the real sticking point), not which method produces “the best” caramelized onions.

    Anyways, thanks for you thought provoking post and turning me onto this subject. In the end I guess it’s just all semantics anyways but I find the debate fascinating.


  6. Yo L’Ed – have you got an e-mail address at which I can contact you?


Comments are closed.