Advisability/Safety of Cooking Acidic Foods in Aluminum Cookware

[Pam Brunning]

I've only owned one aluminum pan--a hand-me-down from my grandmother--and I loved it.  A straight-sided skillet with tall sides, it was the perfect size for almost everything, with a perfectly fitted lid.  Conducted heat well and was lightweight even when full.  Never any oxidation problems.  Not so easy to clean, though.  By the time it finally died, it was looking a little grungy.

But it was a guilty pleasure.  All the hype about stainless steel, etc. made me wonder about my own judgement and standards.  It never impressed dinner guests--to the contrary.  When the rivets on the handle finally failed a year ago, I said a reluctant and appreciative goodbye.  Since then, I've relied on my All-Clad, cast iron, and Le Creuset.  Which I also love, but what I'd really love is to find another aluminum pot like the one Nana gave me.

←

I have several large aluminium pots that I have had for years and use for boiling up bones for stock. I do worry about using them sometimes, maybe that is why my brain is going!!

If you put thin aluminium utensils, such as measuring jugs, in the dishwasher they soon become holey.

[weinoo]

I don't know if I understand why one would season and then scrub?

[Fat Guy]

Seasoning and scrubbing works with cast iron.

[paulraphael]

Seven,

I think think you've partially seasoned that pan. There's more to seasoning than polymerized fat; theres also the carbon that comes from some of that fat burning. This what makes seasoning black, and what makes it slippery.

The most efficient way to do it is to find an oil that's very high in polyunsaturated fat, and that has the smoke point printed on the label. The unsaturated fat molecules are the ones avaliable for oxidation, so using the right oil lets a thin coating produce a much more substantial finish.

Corn oil isn't a bad choice; grapeseed, safflower and sunflower are probably even better. If you can get a brand like Spectrum that tells you the smoke point, then there's little guesswork. Set your oven for about 25 degrees higher than the smoke point, put a very thin coat of oil on the pan, and open a window. Give the pan 30 minutes or so; it will turn very dark. Repeating once, should do it; twice definitely will.

I assume the surface characteristics will be similar to seasoned cast iron. But I have no idea how durable the finish will be in comparison; cast iron has the right porosity to hang onto the coating tenaciously. The other question is, do you want this? A seasoned surface, in my opinion, gives you a more specialized pan. It's great for eggs; it's handy for fish and other delicate protein if you want to be lazy with technique; but otherwise it just gets in the way. It retains and transfers strong flavors, it can discolor light colored sauces, and the dark surface makes it harder to tell how browned your pan drippings are.

Edited June 30, 2009 by paulraphael (log)

[weinoo]

I thought one of the reasons to season cast is so that it doesn't need to be scrubbed. Mine never does.

[Fat Guy]

Then you're cooking in a dirty pan. I always scrub mine and so do restaurants.

[paulraphael]

Then you're cooking in a dirty pan. I always scrub mine and so do restaurants.

←

A well applied seasoning can handle almost any scrubbing you throw at it. I'd stop short of steel wool or ajax.

Most of the mythology about handling seasoned cast iron with kid gloves comes from people's experience with improperly seasoned pans. They thing the greasy film left after cooking is the seasoning!

[Fat Guy]

Yes I think it helps to distinguish between truly abrasive scrubbing with metal and chemicals, and scrubbing with something like a Scotch-Brite scrubbing sponge. That being said I scrub my cast iron with metal after every session.

[slkinsey]

Another possibility is perhaps something like: Aluminum becomes seasoned over time, as it's used repeatedly for cooking. This seasoning, which does not necessarily appear as black or brown but is more along the lines of a sealant, makes the pan less reactive, gives better release properties, etc. A well-seasoned aluminum pan can be used for tomato sauce, berry sauce, et al., no problem. One way to season aluminum is to cook in it over a period of years. The other way is to do what Lincoln Smallwares and Globe Equipment say to do and then rub the brown stuff off with elbow grease but without abrasive scouring.

On a purely chemical basis, reinforced by the appearance of the Beacon pans, this does not seem likely. At the very least, there is no possibility that the "seasoning over time" which you postulate would be the same kind of seasoning which your pretreatment seeks to establish or which is what we commonly think of as seasoning with respect to cast iron (i.e., selective oxidation of iron to magnetite, and the buildup of successive layers of polymerized fat and carbon). There is no way to get that kind of "seasoning" without the dark color. Perhaps there is some enhanced formation of the aluminum oxide layer that can happen over time. That's more difficult to say. Or, of course, it could all just be restaurant mythology and there is no difference.

A good reactivity test for cookware is to melt some butter in the pan and crush some garlic directly into the butter. Often times in reactive pans, the garlic will take on a slight blue-green color. This is actually from copper, and not aluminum, but most aluminum alloys contain copper. It's not a foolproof test, by any means, because the alloy may not contain any copper. But it's one way to look at it.

A well applied seasoning can handle almost any scrubbing you throw at it. I'd stop short of steel wool or ajax.

I don't entirely agree with this. The durability of polymerized fat seasoning is greatly dependent on the hardness of the metal underneath it. Iron is quite hard, and as a result the seasoning on cast iron is durable. Aluminum and carbon steel, on the other hand, are quite soft. Since it is still quite easy to scratch or dent an aluminum or carbon steel pan right through a layer of polymerized fat, it is therefore not nearly as difficult to scour away that layer of polymerized fat (along with a bit of the aluminum underneath). I have easily removed well-established (and in some cases decades-old) seasoning from a carbon steel pan and also from an aluminum broiling pan using nothing more than a Scotch Brite or SOS pad and a bit of elbow grease. This would not be possible with cast iron.

Edited June 30, 2009 by slkinsey (log)

[David A. Goldfarb]

Out of curiosity I checked the Vollrath website for aluminum seasoning instructions, and Vollrath would seem to be the source for the instructions on the Globe Equipment site. Click here to download a PDF from Vollrath--

http://www.vollrathco.com/document_controller.jsp?id=16

Edited June 30, 2009 by David A. Goldfarb (log)

[paulraphael]

The durability of polymerized fat seasoning is greatly dependent on the hardness of the metal underneath it.  Iron is quite hard, and as a result the seasoning on cast iron is durable.  Aluminum and carbon steel, on the other hand, are quite soft.

That's a good point ... I was thinking about cast iron. I have to be a lot more gentle with my carbon steel wok.

[slkinsey]

Out of curiosity I checked the Vollrath website for aluminum seasoning instructions, and Vollrath would seem to be the source for the instructions on the Globe Equipment site.  Click here to download a PDF from Vollrath--

http://www.vollrathco.com/document_controller.jsp?id=16

Right. And I note that they also recommend a similar "seasoning" procedure for stainless steel. Which no one does. In fact, they seem to recommend seasoning of every uncoated metal.

The other question is, do you want this [seasoning]? A seasoned surface, in my opinion, gives you a more specialized pan. It's great for eggs; it's handy for fish and other delicate protein if you want to be lazy with technique; but otherwise it just gets in the way. It retains and transfers strong flavors, it can discolor light colored sauces, and the dark surface makes it harder to tell how browned your pan drippings are.

There is also the problem that the seasoning will burn above a certain temperature, further limiting the utility of the pan.

Edited June 30, 2009 by slkinsey (log)

[Darren72]

Yes I think it helps to distinguish between truly abrasive scrubbing with metal and chemicals, and scrubbing with something like a Scotch-Brite scrubbing sponge. That being said I scrub my cast iron with metal after every session.

←

Interesting. I rub mine with salt, rinse with water, and dry. I do this because I thought you weren't supposed to use soap on a cast iron pan. When you wrote that you scrub with metal, do you mean something like steel wool? What about dishwashing soap?

[LindaK]

Yes I think it helps to distinguish between truly abrasive scrubbing with metal and chemicals, and scrubbing with something like a Scotch-Brite scrubbing sponge. That being said I scrub my cast iron with metal after every session.

Interesting. I rub mine with salt, rinse with water, and dry. I do this because I thought you weren't supposed to use soap on a cast iron pan. When you wrote that you scrub with metal, do you mean something like steel wool? What about dishwashing soap?

I always give my cast iron pans a good scrub with soap. It has never interferred with the seasoning qualities, at least that I've noticed. I like clean pans.

The clinical definition of a "seasoned" pan has always been a little bit of a mystery to me--but it's always clear when a pan is seasoned or not. Can all metal types be seasoned?

[Darren72]

The clinical definition of a "seasoned" pan has always been a little bit of a mystery to me--but it's always clear when a pan is seasoned or not.  Can all metal types be seasoned?

←

I think it is clear (to me at least) that any pan can be seasoned. The question is which pans would you want to season. As best I can tell, the answer appears to be "only non-enameled cast iron".

I have a Staub French Oven (which is enameled cast iron) and I seem to recall that the Staub website said something about the cooking surface improving with use. Their website is under construction now, so I can't get their exact wording.

[paulraphael]

The question is which pans would you want to season. As best I can tell, the answer appears to be "only non-enameled cast iron".

or plain carbon steel, blue/black steel, etc ...

[slkinsey]

I think with carbon steel you can season it in the manner of cast iron, but you don't have to. My carbon steel frypan is seasoned cast-iron style, but my carbon steel crêpe pan has never wanted to season up this way, and does better if I scour it before use and simply preheat with plenty of oil and wipe down before use.

[David A. Goldfarb]

I've been visiting family and we've got a lot of relatives over, so yesterday I made bacon and eggs for breakfast for about eight people with the idea of using the bacon fat to brown the meat for a batch of chili for about ten people at dinner, so I made the bacon using a Calphalon anodized rondeau of around 12 inches and in a bare aluminum Leyse Toroware fry pan of the same size, both of which would be involved in said chili making. Leyse has been taken over by Vollrath, so this pan is of the same weight as a modern Vollrath aluminum pan. I'd guess the anodized Calphalon is around 25 years old, and the bare Toroware is around 35 years old. The bare aluminum has a lot more pitting than the anodized, and the pan has been warped and hammered back a number of times, but it's also been used more for frying on high heat. The metal seems to be of the same gauge in both pans.

It's not a fair comparison, of course, since the burners were different, and the pans are of different design, but I was getting a lot more sticking on the bare aluminum. I was also surprised at how much more even the heat was in the rondeau, which was on a smaller burner and took longer to heat up, but once it was going, the bacon cooked faster and more evenly, mainly I think due to the extra mass on the sides.

Off the topic of the thread, I discovered a beautiful Griswold #9 cast iron skillet that I don't think I've seen for about thirty years, when it would have been at my grandmother's house. It has to be at least 60 years old. I think this is the one that my Grandpa Buster used to use every day to make eggs with onions and potatoes, which I think is what he customarily ate either before or after his shift driving a cab. My father tells a story that once when he was a teenager, he made something in his father's skillet and washed it out afterward, and Grandpa was none too happy. It handled yesterday's eggs with aplomb.

Now I remember my grandmother had a bigger cast iron skillet for fried chicken and such. I wonder if that ended up with one of my cousins.

Edited July 5, 2009 by David A. Goldfarb (log)

[Edward J]

Mmmmm. I wonder if the surface texture of the materials in cookware plays a role in the sticking.

I do know that there are different values or grits of polishing metals. For instance on surgical s/s impliments the metal is polished to a mirror shine, apparantly so that bacteria have a harder time to find a purchase on.

I do know that cooking in a cheap s/s sauteuse and a more expensive s/s sauteuse, meats tend not to stick on the more expensive one. The only logic I can find to expalin this, is because the more expensive one was polished to a higher degree, and theoritically, has a much smoother surface.

Then again, I could be completly wrong. Comments?

[slkinsey]

I think that surface texture probably does make some difference.

If you look at he surface of a pan under a microscope and at high enough magnification, you will see that it appears pitted. These are often called the "pores" of the metal. When you put food into the pan, some of the food goes down into these pores and solidifies, thereby mechanically binding the food to the surface of the pan. This is "sticking."

Different material differ to the extent to which they have these pores. One way of mitigating this problem is with a durable polymerized fat and carbon seasoning layer. This is what we do with cast iron. Another way is to use fat, which fills the pores and creates a transfer medium between the food and the cooking surface.

Another way to handle this is to make sure that the pan is very hot and doesn't get overcrowded and cooled down. The high temperaature makes sure that the food surfaces solidify quickly, before they can bond with the surface of the pan. The Leidenfrost effect may have some effect here as well. Agitating the pan can also help to ensure that food surfaces solidify before bonding with the cooking surface.

Whether surface polish makes a difference if the surface material is the same? I suppose it could make some difference if there were a huge difference in the surface treatment. But more likely than not there are going to be other, much more significant differences. And I suspect that these differences will be minimal compared to the differences between the inherrent porosity of different materials.

Edward, in the case of your two sauteuses, are they otherwise identical except for the surface polish? Or does the more expensive one have a *(better) thermal layer, etc? In my own experience, I have several brands of stainless-lined heavy copper, some with a highly polished inner surface and some with a "brushed" inner surface. There is no difference in their "stickyness."

[Edward J]

The sauteuses? One was a cheap restaurant quality one--JRose, I believe, so maybe Korea or Thailand? The other was a verry old one from my time in Switzlerland--sigh...25 years and that thing still looks like new. I don't know what the "sandwich bottoms" are like, pretty sure the JRose is just a hunk of extruded aluminum glued on and a s/s skin glued onto that. I suspect the Swis one has some copper in there somewhere.

[slkinsey]

So... if the thermal materials are much better of the Swiss piece, that could explain more about the difference in sticking. Or, the psychologist in me can't help mentioning that it could be mostly a perceived difference because you like the Swiss pan a lot better.

[xetaprime]

First of all hello, all! I just had to share this with you even though this thread has history. I recently scored a new old stock Magnalite aluminum pan that also came with the original brochure. The picture reminded me of the first picture posted here. Check it out

 

 

[Thanks for the Crepes]

Welcome to eGullet, @xetaprime, and lucky you.

 

I had to Google to see if my cast iron Wagner Ware skillet was made by the same company as your pan, and sure enough, it was! I hope your piece will prove to be as useful and durable as mine has.

 

Too bad they don't make stuff like this anymore, at least not that us average janes and joes can afford.

[xetaprime]

Thanx! Good to be here! I know, Classic American cookware that was quality made- where'd it go? Not even sure why I've been infected with the Magnalite Bug but I find myself collecting them now. Haven't used them yet but it will be fun cooking in a pan maybe older than I am, I think