The naked truth about bare aluminum cookware

[LindaK]

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.

[Emily_R]

Love this post Fat Guy -- will be eagerly awaiting further results!

[nickrey]

3. How best to clean it? This is one area where I've never done well with aluminum. I don't use much unfinished aluminum (I have a lot of anodized, which plays by different rules) but I have a big stockpot and several half-sheet pans. The stockpot, if you scrub it with a metal scrubber, turns the washing water gray. The sheet pans are easily scratched, not that it matters all that much. What's the deal here?

This is not entirely clear to me. The dishwasher is not the answer, because when I have put aluminum sheet pans in the dishwasher, they have discolored and eventually pitted.

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Sitting in the back of my mind was something I heard about aluminium reacting with dishwashing chemicals with potentially explosive consequences.

Checking the Internet, I found this document which states that the machine dishwashing liquid in question "Reacts with aluminium, zinc, tin and alloys of these metals producing flammable hydrogen gas." Perhaps this is what the lost aluminium from the pits in your sheet pans turned into in your dishwasher Sam.

Edited June 30, 2009 by nickrey (log)

[David A. Goldfarb]

It doesn't seem like a good idea to me either, but neither does reducing berry sauce all afternoon in an aluminum pot. I'm trying to take an open-minded, scientific approach here, and leave behind some of my preconceptions.

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I'm following with interest. My surprise isn't directed at your test so much as the fact that the manufacturer recommends a procedure that apparently no one follows. Apologies if that was taken in the wrong light.

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

[slkinsey]

Right.  Note that this looks nothing like the pans in the pictures from Beacon.

I wouldn't say it looks nothing like them. It's just that the discoloration is much more pronounced. Probably if I scrub harder, or with the next level up of scrubbing sponge, it will look more like this, where the discoloration is less overt but the pan still looks quite different from a new one:

[image snipped]

I think those pan surfaces look radically and fundamentally different. Have a look:

Your pan clearly shows the beginnings of built-up polymerized fat. This is what we would see on a carbon steel pan or, were it not for the color of the iron, a cast iron pan in the early stages of the "seasoning" process. The pan from Beacon just doesn't show any evidence of any polymerized fat whatsoever, except perhaps for the carbonized scunge built up around the rivets. The difference between your pan out of the box and the Beacon pan is that your pan is shiny, unscratched and flat, whereas the Beacon pan is scratched, dull and warped (which is clear when you see the two pans side-by-side).

Yes, it's true that if you get a hard abrasive and scrub away all of the polymerized fat from your aluminum frypan you might have something that looked like the Beacon pan, but you'd get that without building up the polymerized fat in the first place.

What the Beacon pan looks like to me is similar to the grooved "steak broiling pan" my parents have had for around 50 years. It's made of thick aluminum and shaped to fit inside a larger wooden serving platter. I'm sure everyone has seen one. It's scrubbed clean with a hard abrasive every time it's used. I'd be willing to bet that the guys in the Beacon kitchen scrub out their aluminum frypans too.

For your experiment, I think it was worthwhile to follow the instructions and season the pan. But I think it's pretty clear that this is not the condition in which these pans are ever really used. So now it's scouring away the seasoning and starting over.

[Fat Guy]

I see similar discoloration in places on the Beacon pan. To my eye it's a question of one pan evidencing a lot more of it than the other.

One possibility is that the whole seasoning thing is a crock. That certainly seems to be what you're concluding based on theory. It is admittedly the more likely answer. Everything I know about cookware basics says seasoning aluminum is a crock. Then again, watching the dinner service at Beacon was an "everything I thought about aluminum was wrong" moment. So I'm more open-minded at the moment.

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.

Sounds unlikely, but I'm going to pursue the possibility.

[David A. Goldfarb]

Maybe the surface of a freshly spun aluminum pan just has more tooth than one that's been scrubbed and worn down with use, polymerized fats aside. An older pan will have pits and knicks, but maybe the greater part of the surface is just smoother.

[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.

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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.

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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.

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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?

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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)