The Care And Feeding Of Cast Iron

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oldcoot

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On the thread relating to the appropriate use of stainless steel, cast iron seemed to be given a bum rap by some. The indication being that foods – particularly eggs – often stick, that it rusts, and that it is somehow difficult to maintain.



As one who retains, and uses regularly, the several cast iron skillets he used throughout his bachelor days almost 6 decades ago, I feel somewhat qualified to speak – or rather write - on the subject.



Firstly, cast iron (or any other cooking utensil) should not be blamed for the errors of the cook. Used correctly, foods don’t stick to cast iron any more than they do to non-stick products. (And with recent claims that a chemical in the Teflon non-stick coating may be a carcinogen, that is worthy of consideration!) Excessive heat is the usual problem when foods stick. Especially eggs. As Emeril regularly points out, that knob is for regulating the cooking temperature: use it!



Then it is essential to have either water or a fat of some kind between food and metal. Any metal! If that film is not there, the food will stick.



Now, in the case of the subject metal, cast iron, a very simple, but very necessary , procedure must be followed:



To begin with, the pan must be immaculately clean. If a new cast iron skillet, wash it thoroughly and rinse it even more thoroughly, then wipe it dry immediately to prevent rapid oxidation: rust. If an old, crusted skillet, renew it in one of two ways. One easy, the other dangerous! The easy way: using a self cleaning oven, tilt the skillet against a wall of the oven and follow oven cleaning procedure. When cooled, remove it from the oven and wash it as above. If you don’t have a self cleaning oven, this dangerous method can be used – but great care is needed! Using a large plastic container (empty, clean 5 gal. paint bucket?), place the dirty old skillet in the bucket, handle up. Fill the container with cold water to cover the skillet. Now you must be very careful: buy a can of ordinary lye (sodium hydroxide). This stuff is extremely caustic, wear rubber or plastic gloves when working with it, and don’t allow it to get on skin or in your eyes. (If that should happen, flush repeatedly with clean, cold water!!!) Pour very slowly about ½ the contents of the can into the container of water and skillet. Stir gently with a wooden stick to dissolve the crystals of lye. Then lightly cover the container with wood or cardboard. All this should be done outdoors, in a place where neither children or pets can touch it. Leave it for a day or two. Then, using impermeable gloves as before, gently lift the clean skillet from the container. Rinse it thoroughly will cold water, and dry in immediately. Carefully pour the lye water into a sink drain (it will clean your drain pipes just like “Drano”) Never, never let the lye water touch aluminum – it will dissolve it quickly!



Now put your clean, dry , metallic gray colored skillet on a stove burner, and turn the knob to “high”. When the skillet is very hot, turn off the flame and add a little cooking oil. The amount depends on the size of the skillet. Using a folded or crumpled paper towel and a fork, spread the oil carefully over the entire inside of the skillet. Now invert the skillet on a cooling rack, and do the same to the outside. The result will be a shiny, black iron skillet. Let it cool completely, then wipe it dry with clean paper towels. Your skillet is now properly seasoned and ready to perform perfectly.



(Note: While any cooking oil will work – as will lard, Crisco, or bacon drippings – keep in mind the some people are allergic to peanuts, and that olive oil has a very low burn temperature).



When sing your skillet, simply heat it over medium heat, then add a little oil or fat and spread it over the bottom and up the sides a little. The add your food – eggs or whatever. After eggs have set, move them gently with a spatula and continue cooking. If you don’t overheat them, they’ll slide right out of the skillet, perfectly done.



To clean, simply rinse under hot water – NEVER USE ANY SOAP! – and dry with a paper towel.



As Jacques Pepin would say, “Happy cooking!”
 
Nice rundown on the care of Iron cookware. I have a huge iron skillet I use all the time. Although I admit when I burn the bejebus out of it I have had to scrub it with soapy water. But I re-season it as you have descibed when this happens.

I also acquired some really nice sauce pans that are made of iron. I do not keep them seasoned and they rust. Personally I do not mind the rust and will cook with it in the pan. I was told that the rust if anything is beneficial and I have never noticed it chnaging the taste of the food.

If you had a iron pan that needs to be 'reconditioned' because it is in really poor condition would you consider sand blasting it back to the metal? Or would you suggest buckling down and scrubbing ot back down to the iron?

bryan
 
Bknox, it isn't necessary to sandblast or scrub cast iron: merely get it hot enough to burn out all the orrganic material in the pores of the metal. That is precisely what a self-cleaning oven does. Some of that material vaporizes and becomes smoke (lots of it if the pan is in bad shape. The rest burns to ash, and can be rinsed out, and the pan dried to prevent rust. (Washing in a dishwasher will rust the pan every time!) This method returns the pan to its original state, a metallic gray color. Polishing it with non-soap steel wool will make it look like it just came off the store shelf. But that's a wasted effort, since seasoning will give it that beautiful black luster it should have.

As for your cast iron pots, why not season them, too? Then cleaning will require simply rinsing and wiping dry. And they'll look so much nicer than with splotches of rust on them. (And foods won't stick, either, if you use that knob properly!
 
Thanks for the tips. The pan I am refering to has a lot of build up on the bottom I would like to get rid of (the bottom that sits on the stove, not the inside bottom you would cook on). I will try to cook it off in the oven.

Thanks again,
bryan
 
Once a pan is well seasoned there is nothing wrong with using soap on it. Sometimes you just have to. I use soap whn need be and my pans are slick and black.

Make sure you dry it VERY well.

My mother used to put hers in the dishwasher :ohmy: and hers are like teflon.
 
As soaps - especially detergents - are solvents for grease, fats, and oils, it is obvious they will remove the oil, etc., used to season cast iron. It is the tiny amounts of those oils or fats in the pores of cast iron that enable its non-stick properties. Perhaps a quick swipe with soap won't remove all of the oils, and if more is added during the next use, the seasoning might be retained.

A dishwasher is another matter: dishwashing detergent is even more aggressive, and then the relatively long and hot dryiing cycle is ideal for oxidation )rusting_ of the now bare cast iron.

B/w sticks my skillets in the dishwasher all too often, and they invariably come out rusty and I have to reseason.
 
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If I were not such a luddite I would have a camera and would post a pic of my skillets as proof:( . I dont always use soap -- just when I have to for sanitary reasons. :sick: I dry thoroughly and reseason once a year, even if they look like they don't need it.


Luckily my mother doesn't have a dishwasher any more! :ohmy:
Her skillets are going on 50 years old now and are slick as ice.
 
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oldccot, I've only had to "repair" the seasoning on a skillet once after abuse by a housesitter. I put it in the barbeque and covered it with hot coals. Next day I took out a piece of cast iron ready to wash and reseason. Had the rust been deep, I suppose a grinding wheel or the lye treament would have been needed.

but I agree with you, I've never had food stick to properly sesoned cast iron. And for real searing and browning, there is nothing better!
 
Like jennyama - I have a friend who has a VERY, VERY old cast iron skillet - hers can basically have soapy water sit in it all day and it doesn't hurt it - but I'm saying this skillet is probably well over 100 years old too - it's the slickest, shiniest, blackest cast iron skillet I've ever seen (and I'm terribly jealous).
 
Let me weight into this frey with a bit of alternitive reasoning, or speculation at worst. When oil is heated to a sufficeint temperature, the volatile molecules present either evaporate, or leave as smoke particulate mater, along with hydrocarbon gasses. What's left behind is a slick, smooth element called carbon, hence the black color. Anyone who has made pinewood derby cars, and also many industrial workers recongnise carbon for its lubricating properties, though it's usually in the form of graphite.

In any case, when a cast iron pan is well seasoned, the carbon creates an impermeable shell that both protects the metal from oxygen exposure, and creates a very smooth surface that, when covered by a thin film of oil, makes a nearly stick free suface.

When the carbon is thick enough (as happens with months of daily use) soap merely removes a thin outer layer.

Another bit of widom that my wife taught me; To clean any cooking item that has baked on food of any type, and this includes very tough, crusty stuff, is to place the item in a large plastic garbage bag with a glass bowl filled with a cup of amonia. Secure the end of the bag with string or other tying material and let sit overnight. Like lie, amonia is a strong base, and will dissolve the baked on food. IN the morning, just wipe with a paper towel. This method has the advantage of simplicity, and is much less caustic than is lye.

And the warnings about lye are true. I worked at a soda pop factory after graduating high school. One day I stuck my hand into the bottle washer as it had become jammed. I though I was safe because the power was disconnected. After a moment, my skin began to feel like it was burning. Fortunately, there was plenty of cold water available and a simple washing took care of the problem.

The only problem with amonia is that it is an irritant of the breathing organs and so should be left in a well ventilated area, preferably outside.

So to sumarize, season your pans, and wash them with soap only sparingly. They will provide countless years of great service with minimal effort on your part. And yes, I love my cast iron. And that grainy texture found on the new Lodge pans, it goes away and becomes silky smooth with regular use. :mrgreen:

Seeeeeya; Goodweed of the North
 
Ammonia to clean grill grates

The ammonia trick is really good for grill grates and such. With mask and gloves on you place a thick layer of paper towels saturated with ammonia in a big black trash bag then place the grates on top - place another thick layer of ammonia saturated paper towels on top. Let sit overnight. Next day (with mask and gloves on again) you cut open the trash bag and use the paper towels to wipe off the "gunk".

What also works to remove baked on stuff on stovetops (under burners and on burners) is an oven cleaner that has a cold oven method option. I let mine work for more than 24 hours and it worked beautifully!!!!! I also did this on the iinside of my smoker and the grills (I was out of ammonia so I tried this).

Ammonia is also good to add to your dishwater when washing glasses - they come out sparkling clean. Be sure and wear gloves!!
 
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I seasoned a cast iron Dutch oven by coating it with veggie shortening and tossing it in a campfire -- covered with coals, most of the night. Dug it out in the morning, scrubbed it with a stainless steel pad, applied cooking oil. Its' gorgeous.

The "black" in a cast iron pan is FeO3. Rust (orange/brown) is FeO2. What turns orange/brown FeO2 rust into black is hot water. You can cook in the pan or boil it. The orange rust will turn black. FeO2 --> FeO3.

Oil "sets" the FeO3, it's an oxide coating and oil stabilizes it. So, cooking oil and heat . . . good.

Soap and water will remove grease. The oil that sets the oxide in the cast-iron will be removed. Then you expose the surface to rusting -- and you get FeO2, the orange stuff.

Ammonia REMOVES FeO3, along with the grease. We often clean corrosive priming out of gun barrels with ammonia. The ammonia neutralizes the corrosive primer, a mercury compound, but in non diluted strength, it will remove gun blue -- which is a ferrous oxide process (rust).

Alton Brown, on "Good Eats" suggests heating kosher salt in a cast iron skillet, letting it cool and scrubbing the salt with a paper towel -- chemistry and mechanics. The salt removes the water and provides an abrasive for scrubbing the particles out of the pan.

The nice thing about cast iron is that you can burn food particles into carbon and then apply oil. Carbon and oil complement the FeO3 black surface in the pan. Don't ask me about then chemical bond between the carbon and the FeO3. I'm sure there is one, but my chemistry doesn't go that far.

You don't need to clean a rusted cast iron pan in water and lye. It's dangerous, toxic, and a lot of work. Easier to just wash the pan in soap/water, scrub with steel wool to remove the flaking rust (FeO2), oil and heat to a high temp.

I like to season cast iron outside where I can heat the pan way beyond the smoke point of the oil, create a cloud of smoke . . . and not set off the smoke alarms. A gas grill, charcoal grill, or campfire work well for this.
 
Daphe; Good stuff! I always though that the black came from cabon deposits on the iron. Also, when you first get a Lodge brand cast iron pan, the cooking surface is very rough. AFter seasoning, and cooking in it for a bout a year, it becomes smooth, like my old Wagner pans. I again thought that this was caused by carbon deposition in the pits. Am I wrong in this supposition? Is it mearly that the scraping action wears down the peaks?

Seeeeeya; Goodweed of the North.
 
Coating ferrous metals (iron, steel) with oil is the industry-wide accepted method to prevent the oxidation of the metal. The oil prevents the oxygen in air from reacing the iron - it's just that simple.
If cast iron is not so oiled, it will rust even if simply sitting around. Heating raw cast iron simply accellerates that process. As does moisture.

It is not necessary to heat the cast iron to an extreme temperature, thus literally burning the oil. Burning the oil destroys its film-forming capacity, resulting in rusting of the iron.

Raw cast iron is a silvery gray color. Coating it with oil - even without heat - causes light to be reflected differently, resulting in the black color.

Cast iron consists of crystals of iron, between which are empty spaces or "pores". Heating causes metals to expand, and in the case of cast iron, that results in larger "pores" which can more easily be filled with oil (or any fat).
When cooking, the heat causes the oil to expand and form a thin film over the surface, thereby having the same effect as adding oil to any dry cooking surface: non-stick.

This is basically a purely physical (mechanical) action - little or no chemistry is involved.

By the way, there are 3 oxides of iron: ferrous oxide: FeO; ferric oxide: Fe2O3; and feeeous-ferric oxide: Fe3O4.
 
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Okay - I would really need to get my hands on a CRC Chemistry Handbook to address all of the things I've been reading ... but, here's the 25-cent tour of what is going on when you season cast iron or carbon steel.

The oil penetrates into the pores and fissures of the metal ... sealing them against air and water. The heat causes the fatty acid chains to oxidize and bond together (polymerize) and form a dense, hard, dry layer (polymer). If the oil is applied too thick, heated too low, or for too short of a time the polymer layer may be soft and slightly tacky to the touch ... but it will harden up with use. Over time, and as more oil and heat is used, the fresh oil will continue to polymerize and bond to the initial "seasoning" layer until it forms a hard, slick, flat surface.

This is basically what goes on in the cylinder walls of a cumbustion engine in a car during the "breaking in" period.

As far as the black color being from carbonization of the metal ... I really doubt it. I feel safely sure that cooking will not subject a base element to a high enough temperature to turn it into another base element ... iron into carbon .... Fe --> C. I have run seasoned cast iron thru a "self cleaning" cycle in my oven to remove the old seasoning so I could do it over and it came out gray, not black. I have also done this with anodyzed aluminum and had the same results ... the metal wasn't noticeably darker than it was originally.

Just one more thought to throw into the discussion ... :devilish:
 
This button I have for a head can barely follow some of the things I am reading here but I will throw a tip in. I have a 78 year old CI skillet that I bought many years ago at a yard sale. I never use soap in it, I just deglaze, hit it with a light scrubby pad and re-oilo it. I keep it in the oven and whenever I pre-heat...I leave it there. You can literally fry an egg without oil in it.
 
Michael in FTW; If it was I you were referring to when it carbon was mentioned, I did not mean to infer that the metal changed into something else. What I meant was that the fat, which if memory serves me correct, is reduced to a carbon layer as the other matter in it oxidises and either burns away, or vaporizes. And I agree with everything you said, as usual. I too have noticed rough surfaces become noticeably smoother with use. And my eggs, like BubbaGourmet's, slide around quite nicely in my cast iron pans. The only time anything sticks anymore, is if it is sugar based, which may be because the carbon in the sugar molecule bonds to the pan's carbon layer. But that's just a guess. And even then, a bit of hot water removes it easily.

In any case, the physics behind the result is interesting, but not really necessary to us. We only need to know that a properly seasoned cast-iron pan is a truly wonderful cooking utensil when used correctly.

Seeeeeya; Goodweed of the North
 
Naw Goodweed - my comment wasn't directed towards you or anyone in particular ... just a comment on a compilation of comments in general. I could NEVER compete with the guru of cast iron! :rolleyes:

As for the sugar sticking problem - I totally agree - it's probably because of the carbon atoms in the sugar attempting to chemically bond to the oil polymer molecules. Kind of like why you can't whip egg whites in a plastic bowl - because the molecular structure of plastic is so akin to oil that the poor egg whites can't tell the difference.
 
OK, question for all you CI guys. My husband put my frying pan in the dishwasher. It looks ok, but I am not sure if I need to do anything to it.

I should mention here, this is a serious piece of CI. It was my great grammas, and then my Mom's for a zillion years and I have only had it since Christmas.

Do I need to reseason it?
 
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