# Question about why we heat the pan 'before' adding oil.



## crusso

Hello Everyone,

I have heard and read that one should always heat the pan first before adding cooking oil. I don't know why one should do this as compared to adding room temp oil to a room temp pan, and then turning on the heat until the oil is hot enough to cook in.

Does anyone know why we heat the pan first? 

Please let me know, Thanks!

Carmine


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## chrose

Because it's the way we've been taught :smiles: Actually for a home cook I don't know that there's any particular reason that you need to preheat the pan. In a professional setting it helps because it prepares the oil and the pan quicker saving time. The pan heats up quicker because it is empty so there's no resistance acting on it. The oil itself will heat up quick enough when added to a hot pan. Does it save a "lot" of time, no, but every little bit helps. This is assuming of course you are referring to saute type applications as opposed to deep frying!
Just out of curiousity with a CCC and a CCE why are "you" asking this particular question?


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## entropy

"hot pan cold oil, no stick" is what I learned. But this isn't always true because sometimes it depends on the pan. But yes, what chrose said is very very true. Otherwise customers would be waiting much much longer for their food.


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## blueicus

I heard that there's no real evidence to support the hot pan cold oil no stick policy versus cold pan cold oil heat up no stick, they both work just as well... but it is true that overheated oil for long periods of time does break down the oil so you only want it hot if you're actually doing something with it very soon.

The real key to no stick while cooking meat is to not jostle the meat around until the outside has cooked thoroughly.


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## phoebe

In a class, I was told that the "pores" of the pan expanded as the pan heated and then, when you add the oil, it would get into the pores and create a more even coating to prevent sticking. Sounded good at the time :look:


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## powers

True...... The metal(depending on what kind) has a grain that is full of pores will expand to allow the oil to settle in those pores. If you add oil to cold pan the surface tension of the oil is so great that it will "pool" and rest on top of those poors, when you add protien, the weight of the protein will push the food product into the grain which is not lubricated and your food will stick. That doesn't apply to nonstick which are prelubricated in all pores.

I just wanted to see how many times I could write lubricate


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## blueicus

I've heard that explanation before, but is it actually true, or some bizarre pseudo-science that isn't exactly as it seems? I remember Alton Brown talking about this subject but forgot the main points.


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## entropy

One thing I know for sure from experience is that food will be cooked much more effectively if you start out with a hot pan. Ever try searing meat starting with a cold pan? Good luck, eventually it will caramelize over high heat but then it will be completely overcooked. And you can forget about getting that perfectly crisp skin on a piece of black bass. Also, if you are going to saute vegetables or meat starting with a cold pan, all the water that gets released won't evaporate as quickly and can ruin the whole dish, even if the pan is underloaded. I never start with a cold pan, unless I'm heating up water, melting sugar, or reheating something else. Of course, you don't necessarily want to start out with a smoking hot pan either, it just depends on what you are cooking.

Also, adding cold oil prematurely to a cold pan retards the whole heating process, minimally so, but every split-second makes the difference in a professional environment. At home, it doesn't matter.


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## chrose

And a fine job you did :smiles:

From Kitchen myths: Source: http://www.pgacon.com/KitchenMyths.htm


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## blueicus

I don't think any of us are disputing that one should saute or sear on a hot pan, but the whole whether or not oil should/could be put on a hot/cold pan dispute .


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## entropy

ha ha ha:lol: :lol:

Your point's well taken, but I guess the answer just isn't that simple. It depends on what you're cooking, how you're cooking it, and what you are cooking it in. _It never hurts to start with a heated pan_, but you don't _always_ have to start with a hot pan. Its just a concept full of variables.


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## crusso

Thanks for your thoughts. I've heated pans all my life, but when I wanted to find out if taking longer to heat the oil (because of adding it to a cold pan) might affect it in some way, I tried looking in several books and could not find anyone addressing the 'why' of pre-heating pans, besides the obvious saving of time.

Again, Thanks

Carmine Russo


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## phoebe

I've been poking around in McGee, Russ Parsons, and Robert Wolke, but no luck. It does sound like something Alton would have gone on about, but I can't find that either. All that I came across was this quote in the saute section of _The Pro Chef_ 7th ed.: "Preheat the pan and add the cooking fat. Heating the pan before adding the oil is referred to as conditioning the pan."


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## cheflayne

I have worked at a lot of restaurants that use aluminum saute pans. Most of those pans have bottoms that have popped out and are no longer flat which can be a pain. This popping out is caused by heating the pan dry, putting oil in first prevents this from happening.


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## foodpump

Oh, stamped aluminumn will do that even if you started off cold, it's just the nature of aluminum, and carbon steel too, for that matter. Cast aluminum not so much, but then there are very few commercial cast aluminum pans. 'Course, I could write a 3 page essay on why I hate aluminum, but then I'd be off-topic...

My 2 cents on the matter? Nothing irritates me more than watching someone put a cold raw piece of meat into a cold pan, put in the heat, then drizzle oil onto it as an afterthough. Terrible things hapen to the meat, tough, stringly and leached of oil juices, then boiled in the resulting juices once the pan gets to the right temp. 

So how can you insure that this won't happen? As a Chef or instructor, how do you instruct the newbie cook to look for a telltale signal when it's time to put the meat into the pan? 

Make sure the pan is #$%!-ing hot BEFORE adding in the product. 

How do you know if it's hot? 

When the oil shimmers and starts to haze. 

Cold pan, hot pan, fan schman, when the oil's good and hot THEN it's time to cook, and not a second before.


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## blade55440

One thing my instructor told me about hot pan and oil is that when your pan is hot, you tend to use less oil (the same amount tends to cover more when it's hotter, than when trying to coat a cold pan).

Granted she went on the same "it'll stick" shpiel... but doesn't everybody get that one?


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## kuan

Maybe if you get the pan hot enough the oil will polymerize on contact and create a sorta non-stick surface.

Hmmm...


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## chrose

Brilliant!!!!!!!!!!!!!!!!!!:chef:  :lol: Ahh Kuan....always thinking! You little scientist you :beer:


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## cacook

I don't know any of the science for it, but the reason I preheat is to save a little time. You can set the pan on the range and get it going, go and grab your stuff, then by the time you get back to add your oil it'll heat up much quicker than starting from both being cold. If you let it heat up with the oil in it and it starts smoking before you get back, you've just wasted oil.


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## brittany

When I worked as saucer at a super busy restaurant, during the really crazy times, I would continually place pans in the bottom of the oven so that they were already smoking hot and it would take two seconds to get the oil sizzling hot. I miss those days. Always out thinking time, being a step ahead of the customers, being a step ahead of the chef.
Anyways. Something I have been taught is that olive oil is not heated in a cold pan because you do not want it to reach smoking point. It will tastes bitter due to all the plant partlicles in the oil (cold pressed, xtra virgin). So my chef would have me heat up the pan, when the pan was smoking, I would then add the oil and proceed to cook when i could smell the olive oil. Which was pretty much right away. I would also season all my pans with that chef because he used oil as a flavor and not just a cooking method, thus, sometimes you were limited on how much oil you could cook with.


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## 86general

crusso said:


> Hello Everyone,
> 
> I have heard and read that one should always heat the pan first before adding cooking oil. I don't know why one should do this as compared to adding room temp oil to a room temp pan, and then turning on the heat until the oil is hot enough to cook in.
> 
> Does anyone know why we heat the pan first?
> 
> Please let me know, Thanks!
> 
> Carmine


Ok so a) I'm not a professional chef, just a pandemic-stay-home-inspired cooking enthusiast, and b) I realize I am 16 years late to this discussion. So please forgive me if the questions I ask seem dumb or amateurish. That said…I have a question for pro chefs about this issue: It seems the majority opinion is that the hot pan first is best. Assuming it is, how do you approach this with tin-lined copper pans and non-stick pans (both of which I believe are quite popular in professional kitchens)? I have some new copper pans that I love, and the guy who made them for me explained that the tin can melt if overheated and so there needs to be something in the pan before it gets too hot … and of course the same applies to non stick pans, as anyone who has forgotten one that's on a flame and watched it delaminate can attest.
Do you still pre heat your copper/tin for sautéing ? Or do you not use copper tin to sauté? Or do you heat copper tin with the oil, not before? Thanks everyone.


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## brianshaw

Reading this thread has been a "blast from the past"; thanks for reviving it! Better late than never. The mid 2000's were good years for me. In fact, last night I drank a bottle of 2005 California red wine... it was great.

In those days I heard Matin Yan say "hot pan, cold oil; food won't stick" so often that it has become one of his familiar mantras. And so did the Frugal Gourmet.

To me it makes sense when one thinks about how a pan heats, especially with a gas stove. It takes a while for the pan to become evenly hot, especially near the handle where there is a large radiator that takes longer to heat up. So starting the pan off hot could avoid overheating/burning the oil or having the oil cool off too much when food is introduced.

I'm not an advocate of overheating pans, which seems to be what some do in the attempt to get a "screaming hot" pan in the restaurant style. For frying I'll heat the pan gently over a low flame until it feels evenly hot, especially near the handle. The add the oil, crank up the heat to an appropriate temp, check the oil temp, and cook the food. This works for copper too as it won't, if you monitor the pan while heating, let the pan overheat and ruin the tin coating. The key (as it seems you already know) is to pay attention to the pan once the fire is lit.


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## phatch

From "The Wok" by Kenji Lopez-Alt



> Will a Hot Wok and Cold Oil Really Prevent Sticking?
> There's a basic rule of thumb in wok cooking that goes like this: a hot wok and cold oil will prevent your food from sticking. The idea is that you preheat your wok over high heat until it is ready to cook, then add your oil immediately before adding other ingredients.
> But does this technique really work, and is it really the best way?
> Let's quickly take a look at exactly what makes food stick in the first place. You may have heard that food sticks to pans by getting stuck in microscopic pores in the metal and that oil prevents this by filling those pores and creating a smooth surface. This is not true. Raw proteins interact with metal on a submicroscopic level, forming actual molecular bonds. Even on a perfectly smooth, polished surface with no cracks or imperfections whatsoever, meat will stick to hot metal.
> How does preheating prevent this? The thing is, only raw proteins will form this bond. Heat causes proteins to fold in on themselves, or even to break down and form all new compounds. Once in their folded or rearranged form, they no longer stick. So the goal is to get surface proteins to cook before they even come into contact with the metal by heating a film of oil hot enough that it can cook the meat in the time it takes for it to pass from the air, through the film of oil, and into the pan.
> With Western-style cooking, I almost _always_ add oil to the pan before I start to preheat it. It's a useful method of telling how hot your pan is. When the oil becomes very loose and starts shimmering (around 300° to 400°F), you're in sauté territory. When it starts to smoke lightly (400° to 500°F, depending on oil type), you're ready to sear, and when it starts to smoke heavily or you see flames licking across the surface, it's a sign that you should probably stop reading your social media feeds and focus on cooking.
> So what about this hot pan, cold oil thing? It never really made sense to me; when you add a relatively small amount of oil to a really hot pan, it nearly instantly heats up to the same temperature as the pan-precisely the same temperature it would hit if you heated it up with the pan in the first place. Naturally, I thought that preheating the oil with the wok would work just as well for stir-frying. So I tried it side by side.
> I found that whether I heated up the oil with the wok or added oil to an already preheated wok, my food was equally unlikely to stick. But there was one big difference: flavor. With stir-fries, you typically preheat the wok even hotter than you would heat a Western skillet for searing. If you start with oil in a cold wok, by the time it's hot enough to start cooking, the oil will have already broken down a great deal, producing free radicals and acrolein, which gives stir-fries a burnt, acrid flavor.
> It turns out that as with much accepted wisdom, this one is right, but for the wrong reasons.
> 
> Nonstick coatings like Teflon are specially engineered to be smooth and virtually nonreactive, meaning that these types of molecular bonds will not form even if you start cooking in a cold pan. The problem with nonstick is that most nonstick coatings can't be heated hot enough to sear properly, nor are they robust enough for the vigorous scraping and tossing required for a good stir-fry.
> Incidentally, if you've watched any episode of Sichuan chef Wang Gang or Guizhou-based couple Stephanie Li and Christopher Thomas's excellent instructional videos on YouTube, you'll be familiar with the concept of _longyau_. It's a technique restaurant chefs use to season their woks to prepare them to accept food. The idea is that rather than adding a measured amount of oil to the preheated wok before cooking, you add a large amount of oil, swirl it around to coat, then dump the excess oil out, leaving the wok slicked and ready to go.
> To successfully practice longyau, you need to have a separate saucepan or other heatproof container on your stovetop filled with oil, which you can ladle into your wok, then dump back in after swirling. If you stir-fry frequently enough to have a permanent longyau oil pot on your stove, this is a useful technique to keep in your arsenal.
> 
> Smoke Signals: How to Tell When Your Wok Is Hot Enough
> 
> _But wait a minute_. _Without the visual cues that preheating oil provides, how can you tell if your wok is hot enough?_ Easy. The wok does this all by itself. A well-maintained and seasoned cast iron or carbon steel surface should always have a very thin layer of oil coating its surface, which means that even without added oil, you'll still see light smoking when it hits stir-fry temperatures. Just to make sure, I'll often rub a small amount of oil into the surface of the wok with a paper towel before preheating. This small amount of oil is not enough to produce off flavors in your stir-fries, but it's enough to indicate the surface temperature of the wok. Once it starts smoking, I add the remainder of my cooking oil, immediately adding my first stir-fry ingredients, which lowers the temperature of the wok and oil enough that the oil will not burn.


He includes some interesting graphs and more details. Worth looking at if this is a topic that interests you.


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## cheflayne

phatch said:


> From "The Wok" by Kenji Lopez-Alt
> 
> With Western-style cooking, I almost _always_ add oil to the pan before I start to preheat it. It's a useful method of telling how hot your pan is. When the oil becomes very loose and starts shimmering (around 300° to 400°F), you're in sauté territory. When it starts to smoke lightly (400° to 500°F, depending on oil type), you're ready to sear, and when it starts to smoke heavily or you see flames licking across the surface, it's a sign that you should probably stop reading your social media feeds and focus on cooking.


I second this big time. Pretty much nails it from my point of view and work experience.


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## STEPHEN WOODARD

I'd think some poultry would benefit from starting with a cold pan, duck and chicken when rendering the skin. Bacon, and a few others.


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## 86general

STEPHEN WOODARD said:


> I'd think some poultry would benefit from starting with a cold pan, duck and chicken when rendering the skin. Bacon, and a few others.


I usually start bacon in a cold pan and heat it slowly for just this reason. I learned this by trial and error, mostly error  Jacques Pepin also has a video where he cooks chicken thighs skin side down starting in a cold, non-stick pan. After cooking a few minutes on high-ish heat to brown the skin, he finishes them by covering the pan and steaming. They come out great, and you end up with this nice little puddle of chicken fat.


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## West-Coast-Cook

The hot pan>cold oil>food no stick is the rule I always_ adhered_ to (sorry folks, second post and I'm already slipping puns in, better moderate my first hundred or two posts, mods!).

Seriously...I've forgotten to heat the pan first, many times, and never noticed any sticking.

I did watch a recipe (can't recall it) from America's Test Kitchen, wherein they suggested to put both oil _and_ garlic into the cold pan to help the flavor of the garlic _bloom _(in that particular recipe), which I immediately tried in a pasta gravy, and didn't see any great change, either, but then the gravy was cooked for several hours.


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## brianshaw

For pasta sauce I can see the cold start for a gentle release of flavor. I assume that both pasta sauce and pasta gravy respond positively from that technique.

Love the pun; it got past me initially. Welcome to the forum!


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## phatch

I've never been all that impressed with a cold start over more conventional technique generally. But then I don't cook fatty fowl skin on in a pan with any frequency to generate much of a sampling base.


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## chrislehrer

Okay, I don't know how this discussion got to be non-pros allowed, but as long as it is so, I'll put in my $.02 on fatty fowl. The duck thing works beautifully, but only if you prep correctly. You have to score the skin right down to (but not into) the flesh, in a reasonably even pattern (diamonds are traditional and pretty). Season generously, lay in cold pan, turn heat to medium-high. By the time the skin is brown and crispy you'll have rendered out a %&$^$-ton of fat. Then you flip the breast over and cook a couple minutes just until rosy-pink-done. The whole point is that you're heating slowly to melt out as much fat as possible. If you think about it in temperature terms, it's exactly the same as cooking diced onions in water with a little butter until the water boils off and then finishing the caramelization in the remaining butter (a trick that also works with lardons): you're breaking down the material at low temperature so that the caramelization process acts quickly and doesn't require as much monitoring. None of this has anything to do with why you should do hot-pan, then oil, then sear (on which IMHO Kenji nailed it).


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## surfcast

crusso said:


> Hello Everyone,
> 
> I have heard and read that one should always heat the pan first before adding cooking oil. I don't know why one should do this as compared to adding room temp oil to a room temp pan, and then turning on the heat until the oil is hot enough to cook in.
> 
> Does anyone know why we heat the pan first?
> 
> Please let me know, Thanks!
> 
> Carmine


Only one way to know for sure try it both ways? See if it less sticky, I don't see it being a real biggie either way!


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## butzy

phatch said:


> From "The Wok" by Kenji Lopez-Alt
> 
> 
> He includes some interesting graphs and more details. Worth looking at if this is a topic that interests you.


Great article @phatch


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## JohnDB

Several things come to mind....
Salt, oil, heat, and aluminum or steel. 

Aluminum and salt both can break down oil and make them rancid in a heartbeat. (Seasoning on the meat)

Seasoned cast iron or carbon steel are great....but the polymerised oils will break down the oils in the pan too....but slower than the salt or aluminum will. 
So if the pan is hot and the oil is cold there are two benefits. 

No rancid oils and no fire hazard for most home cooks. 
Oil heated to Flashpoint ....been there;done that on a daily basis. At home the smoke detectors tell you cooking is happening. But under a commercial hood no big deal....most fires at home start in the kitchen. Smoke damage is the least but most common occurrence. 

Those are the reasons I know of.


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## retiredbaker

chrose said:


> And a fine job you did :smiles:
> 
> From Kitchen myths: Source: http://www.pgacon.com/KitchenMyths.htm


yeh? who's kitchen , those people obviously don't work in kitchens.

In a busy commercial kitchen the pans are kept HOT whenever possible.
No oil means no smoke.


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## EllenChef1

Brilliant!!!


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