Calphalon Anodization Breakdown?

[Matt_T]

I have a 8.5qt Calphalon Commercial stew pot. It's about 11" wide by 5" high; they may call it a dutch oven. It's not nonstick, and has the same hard-anodized finish inside and out.

I've noticed the anodization on the inside bottom is starting to break down. The dull gray is turning into interesting irridescent swirls. No bare aluminum showing yet, but some of the anodization is yellowish and I think getting thin and/or soft. I tried to take some pics but with my limited skills, none of my shots look anything like the reality. The pot's a few years old but I think most of this damage happened one time when it got a little overheated while being used with a steamer insert, almost boiled dry.

Anybody think there's any health risk to continuing to use this pan? I use it mostly for acidic dishes like cioppino, chili, and coq au vin, and I've heard that long-simmering acidic dishes in bare aluminum is a no-no.

Edit: if I do replace the pot, what do people think of the newer Calphlon One Infused (not nonstick)? From what I read this product (even the non-nonstick) has plastic integrated into the finish and I wonder about using it over high heat for browning. All-Clad MC2 a better choice? I have a Le Creuset cocotte near this size also, but the Calphalon browns much better (and I expect the AC would too).

Edited April 12, 2008 by Matt_T (log)

[paulraphael]

I have a lot of old (early 1990s) calphalon, and the anodizing has largely worn away on the insides of every piece. I haven't seen colorful swirls ... just a lightening of the gray and then silver peeking through. I use the pieces the same as always. Even though there's the possibility of acidic food leaching aluminum from the thinned parts, it hasn't been an issue in practice. No off flavors or colors.

I do find it annoying, considering how much they boasted about the invulnerability of the anodizing. It's just not a very robust surface. I should add that the pans haven't been abused. They've been cleaned and handled according to the company's recommendations. I'm pretty certain the wear is chemical, not physical. There is no hint of wear on the outsides of the pans wear they get banged and dragged over cast iron stove grates.

In the final analysis, I give the company a thumbs-down. Because of the impermanence of the anodizing, the unknown permanence of their newer surfaces, and my growing preference for stainless steel, I plan to replace these pieces with other brands when the time eventually comes.

[Fat Guy]

If you're concerned about the culinary aspect of things, you just need to monitor flavor and color. If you're not noticing any changes, there's nothing to worry about.

If you're concerned about health, well, you're not going to get easy agreement about the dangers of aluminum. One thing I'll say, though, is that if you're concerned about the health impacts of unfinished aluminum pans you should probably stop eating in restaurants altogether. Restaurant kitchens -- especially in the non-fancy restaurants where they can't afford expensive Bourgeat-type stuff -- are full of unfinished aluminum. Walk past any restaurant-supply shop in your city's industrial area and see what all the commercial stuff is really made of. So, if you're going to dine out, it's probably not worth worrying about a little exposed aluminum on your home cookware.

[Richard Kilgore]

Calphalon and/or retailers who carry it are pretty good about standing behind their products. You may want to ask if they will replace it. I had a similar problem with some very old pieces several years ago and Williams-Sonoma offered to replace them with same or give me store credit.

[Matt_T]

Thanks for the replies. So far nobody's come up with the "right" answer, which would be "That pan is deadly! You must, must run out immediately and replace it with Falk copperware!" Note that any such answers should be cc'd to my wife.

Joking aside, I wanted to put in a positive word for Calphalon. We have a bunch of it and it's really held up well in our home kitchen. This particular piece, as I mentioned in my first post, was really abused in that is was allowed to boil almost dry over high heat. But it didn't warp or burn. Some of our oldest pieces, like the 12" skillet, 4 qt chef's pan, and 4.5qt saucepan which all go back to the late 90s, get used several times a week and can still be made to look almost like-new with a little Barkeeper's friend and elbow grease. I did have a 5-qt saute warp once, bulging down in the center so that it wobbled badly, but even that was restored to usability with the aid of a rubber mallet. Good anodized aluminum cooks great too, searing better than Le Creuset or the mid-priced stainless pans we've tried, making good fond while being nonreactive...

Don't want to turn this into a Calphalon commercial, just to make clear that this one story of premature wear was not meant as a bash of the product overall.

[jsmith]

That pan is deadly! You must, must run out immediately and replace it with Falk copperware!

[miles717]

The pan certainly isn't deadly unless wielded as a blunt instrument. As others have already noted, the bulk of the cookware in restaurants is plain aluminum. I'd suggest that you send it to Calphalon to see if they'll replace it. Assuming that you have more or less decided to replace it anyway, it may be a far less expensive option than buying something new. Unless you're dying to spend the money, I'd give it a try. They have a good reputation for backing up their warranty without questions or hassles. I have personal experience with them in this regard and can honestly say that it was a great experience.

I recently shipped a Commercial NS saute pan back to Calphalon for warranty replacement (NS was starting to wear away and the anodization on the bottom of the pan had been worn through due to excessive "shaking and stirring" on the old electric burners in our last house). I had heard they are quite good about honoring their lifetime warranty, so I figured ten dollars in shipping was worth sending it to them to see what would happen since I simply couldn't continue to use the pan with the NS coating in that state and would have replaced it anyway. Despite the fact that I certainly had gotten more than my fair share of use out of the pan, they shipped me a brand new One NS pan, much to my great surprise and delight. I couldn't be more pleased with the performance of the new pan.

[takadi]

Isn't consumption of aluminum tainted products correlated with Alzheimer's?

[slkinsey]

No, it isn't. That was debunked years ago. So, no worries on that front.

[johnnyd]

I did have a 5-qt saute warp once, bulging down in the center so that it wobbled badly, but even that was restored to usability with the aid of a rubber mallet.

You can do that? My 12" fry pan bulged out a couple years ago and I'm tired of propping it up with a salt shaker.

[paulraphael]

I did have a 5-qt saute warp once, bulging down in the center so that it wobbled badly, but even that was restored to usability with the aid of a rubber mallet.

You can do that? My 12" fry pan bulged out a couple years ago and I'm tired of propping it up with a salt shaker.

←

Yep! Although I uncermoniously used a steel hammer (with a bit of tape on the end to protect the finish). My calphalon 10" frying pan and 2-1/2 qt. saucepan have been de-wobbled with said cave man technology.

Heavy aluminum will warp if you use it a lot with high heat. I don't think there's any way to get around it. My calphalon is the old stuff (from when it just said "commercial aluminum cookware company" on the pans. It's 5mm or 6mm thick. I suspect this thicker aluminum is even more prone to warping than the the newer thinner stuff.

[slkinsey]

Actually, it's the other way around. The thicker the aluminum, the less prone to warping it is.

[andiesenji]

I have had several "silvered" original Calphalon pieces - still using the 16-quart stockpot, no problems. Returned two or three skillets, a casserole and an 8-quart stockpot for replacements because I use them for tomato sauces, reducing wine, etc., (high acid) and although I never noticed a metallic taste, thought that since they have a lifetime guarantee, why not take advantage of it. No problems.

The wide, deep sauté pan that developed silvering was relegated to the outdoor barbecue "kitchen" and has been doing duty rendering duck fat and similar tasks.

[Matt_T]

Thanks again!

Yes, I have pounded a number of thick aluminum pans into shape with a rubber mallet. The saute was the only one of the anodized pans I use at home that's needed it, but at our firehouse I've had to reshape a couple of big 14" plain aluminum skillets more than once. I set them rim-down on a sturdy workbench with a layer of newspaper in between, and start poundin'. Note that hearing protection is highly recommended!

[dougal]

...

I've noticed the anodization on the inside bottom is starting to break down.  The dull gray is turning into interesting irridescent swirls.  No bare aluminum showing yet, but some of the anodization is yellowish and I think getting thin and/or soft.  I tried to take some pics but with my limited skills, none of my shots look anything like the reality.  The pot's a few years old but I think most of this damage happened one time when it got a little overheated while being used with a steamer insert, almost boiled dry.

...

←

Ummm. It doesn't sound like the anodisation is breaking down.

Might even be building up...

"Irridescent" colour is an immediate indicator of "interference" colours, produced by films so thin that they bear comparison with the wavelength of light - commonly seen with a drop of petrol/gasoline on a puddle of water.

"Anodisation" is the production of a hard alumina surface by electrochemical means.

If the steamer insert was *not* aluminium (maybe stainless?), then with conductive (salted?) liquid in the pan, you'll have some electrochemistry going on. Hopefully not very much though.

As the pan boiled dry, so the mineral concentration in the water would increase, eventually hitting the limit of solubility - saturation.

If the electrochemical conditions were depositing stuff on the aluminium side, it could have built up a really thin layer of new stuff, incorporating stuff from the saturated solution...

In short, the appearance of the irridescent colour indicates a new, thin, (more or less transparent) layer that isn't exactly the same as what's underneath it - making an interface in the solid, from which light could be reflected, interfering with light reflected from the top surface.

Hence, I think its possible that your boiling dry with a steamer insert may have *deposited* a new (very thin) layer of anodisation - rather than "breaking down" what was there before.

If the new stuff is stable (doesn't come off when cooking or cleaning) then I doubt its going to do any harm. However, if the swirls are changing when you scrub at them, it'd indicate that you were removing material from the new film layer, and changing the interference patterns...

So, if you really are sufficiently determined, you might still be able to work this around to an argument justifying replacement...

[ray goud]

...

I've noticed the anodization on the inside bottom is starting to break down.  The dull gray is turning into interesting irridescent swirls.  No bare aluminum showing yet, but some of the anodization is yellowish and I think getting thin and/or soft.  I tried to take some pics but with my limited skills, none of my shots look anything like the reality.  The pot's a few years old but I think most of this damage happened one time when it got a little overheated while being used with a steamer insert, almost boiled dry.

...

←

Ummm. It doesn't sound like the anodisation is breaking down.

Might even be building up...

"Irridescent" colour is an immediate indicator of "interference" colours, produced by films so thin that they bear comparison with the wavelength of light - commonly seen with a drop of petrol/gasoline on a puddle of water.

"Anodisation" is the production of a hard alumina surface by electrochemical means.

If the steamer insert was *not* aluminium (maybe stainless?), then with conductive (salted?) liquid in the pan, you'll have some electrochemistry going on. Hopefully not very much though.

As the pan boiled dry, so the mineral concentration in the water would increase, eventually hitting the limit of solubility - saturation.

If the electrochemical conditions were depositing stuff on the aluminium side, it could have built up a really thin layer of new stuff, incorporating stuff from the saturated solution...

In short, the appearance of the irridescent colour indicates a new, thin, (more or less transparent) layer that isn't exactly the same as what's underneath it - making an interface in the solid, from which light could be reflected, interfering with light reflected from the top surface.

Hence, I think its possible that your boiling dry with a steamer insert may have *deposited* a new (very thin) layer of anodisation - rather than "breaking down" what was there before.

If the new stuff is stable (doesn't come off when cooking or cleaning) then I doubt its going to do any harm. However, if the swirls are changing when you scrub at them, it'd indicate that you were removing material from the new film layer, and changing the interference patterns...

So, if you really are sufficiently determined, you might still be able to work this around to an argument justifying replacement...

←

Finally!!! Someone who knows what he speaks of! The dark gray color was the dye Calphalon used when they initially made the pot. Normally the anodized layer would have been colorless or slightly cloudy but "silvery". Unless someone scrubbed the pot with steel wool, really vigorously, there is no indication that the anodized layer has disappeared.

Ray

[qrn]

...

I've noticed the anodization on the inside bottom is starting to break down.  The dull gray is turning into interesting irridescent swirls.  No bare aluminum showing yet, but some of the anodization is yellowish and I think getting thin and/or soft.  I tried to take some pics but with my limited skills, none of my shots look anything like the reality.  The pot's a few years old but I think most of this damage happened one time when it got a little overheated while being used with a steamer insert, almost boiled dry.

...

←

Ummm. It doesn't sound like the anodisation is breaking down.

Might even be building up...

"Irridescent" colour is an immediate indicator of "interference" colours, produced by films so thin that they bear comparison with the wavelength of light - commonly seen with a drop of petrol/gasoline on a puddle of water.

"Anodisation" is the production of a hard alumina surface by electrochemical means.

If the steamer insert was *not* aluminium (maybe stainless?), then with conductive (salted?) liquid in the pan, you'll have some electrochemistry going on. Hopefully not very much though.

As the pan boiled dry, so the mineral concentration in the water would increase, eventually hitting the limit of solubility - saturation.

If the electrochemical conditions were depositing stuff on the aluminium side, it could have built up a really thin layer of new stuff, incorporating stuff from the saturated solution...

In short, the appearance of the irridescent colour indicates a new, thin, (more or less transparent) layer that isn't exactly the same as what's underneath it - making an interface in the solid, from which light could be reflected, interfering with light reflected from the top surface.

Hence, I think its possible that your boiling dry with a steamer insert may have *deposited* a new (very thin) layer of anodisation - rather than "breaking down" what was there before.

If the new stuff is stable (doesn't come off when cooking or cleaning) then I doubt its going to do any harm. However, if the swirls are changing when you scrub at them, it'd indicate that you were removing material from the new film layer, and changing the interference patterns...

So, if you really are sufficiently determined, you might still be able to work this around to an argument justifying replacement...

←

Finally!!! Someone who knows what he speaks of! The dark gray color was the dye Calphalon used when they initially made the pot. Normally the anodized layer would have been colorless or slightly cloudy but "silvery". Unless someone scrubbed the pot with steel wool, really vigorously, there is no indication that the anodized layer has disappeared.

Ray

←

Question about the anodizing...Calaphon recomends that you clean their pans with Scotchbrite pads. They are basicly sandpaper. I have cleaned some of mine several times and the grey color remains as new. How or what do they do to get it grey??

My only experience with anodizing is I was going to anodize a dough hook and got the whole set up arranged and it would not anodize....Duh! it was zinc pot metal,,,

Shows how much I know...

Bud

[ray goud]

...

I've noticed the anodization on the inside bottom is starting to break down.  The dull gray is turning into interesting irridescent swirls.  No bare aluminum showing yet, but some of the anodization is yellowish and I think getting thin and/or soft.  I tried to take some pics but with my limited skills, none of my shots look anything like the reality.  The pot's a few years old but I think most of this damage happened one time when it got a little overheated while being used with a steamer insert, almost boiled dry.

...

←

Ummm. It doesn't sound like the anodisation is breaking down.

Might even be building up...

"Irridescent" colour is an immediate indicator of "interference" colours, produced by films so thin that they bear comparison with the wavelength of light - commonly seen with a drop of petrol/gasoline on a puddle of water.

"Anodisation" is the production of a hard alumina surface by electrochemical means.

If the steamer insert was *not* aluminium (maybe stainless?), then with conductive (salted?) liquid in the pan, you'll have some electrochemistry going on. Hopefully not very much though.

As the pan boiled dry, so the mineral concentration in the water would increase, eventually hitting the limit of solubility - saturation.

If the electrochemical conditions were depositing stuff on the aluminium side, it could have built up a really thin layer of new stuff, incorporating stuff from the saturated solution...

In short, the appearance of the irridescent colour indicates a new, thin, (more or less transparent) layer that isn't exactly the same as what's underneath it - making an interface in the solid, from which light could be reflected, interfering with light reflected from the top surface.

Hence, I think its possible that your boiling dry with a steamer insert may have *deposited* a new (very thin) layer of anodisation - rather than "breaking down" what was there before.

If the new stuff is stable (doesn't come off when cooking or cleaning) then I doubt its going to do any harm. However, if the swirls are changing when you scrub at them, it'd indicate that you were removing material from the new film layer, and changing the interference patterns...

So, if you really are sufficiently determined, you might still be able to work this around to an argument justifying replacement...

←

Finally!!! Someone who knows what he speaks of! The dark gray color was the dye Calphalon used when they initially made the pot. Normally the anodized layer would have been colorless or slightly cloudy but "silvery". Unless someone scrubbed the pot with steel wool, really vigorously, there is no indication that the anodized layer has disappeared.

Ray

←

Question about the anodizing...Calaphon recomends that you clean their pans with Scotchbrite pads. They are basicly sandpaper. I have cleaned some of mine several times and the grey color remains as new. How or what do they do to get it grey??

My only experience with anodizing is I was going to anodize a dough hook and got the whole set up arranged and it would not anodize....Duh! it was zinc pot metal,,,

Shows how much I know...

Bud

←

I hope someone was joking about cleaning with scothbrite! Cleaning with a sandpaper-infused plastic pad WILL remove the anodized layer.

The color is a dye introduced after the anodizing process. Nowadays you can get any color you want.

[Fat Guy]

Scotch-Brite refers to a whole line of products, some of which are formulated to be safe for non-stick and other easily scratchable surfaces. They say "NO SCRATCH" prominently on the packaging.

I'm not 100% convinced by the buildup hypothesis. I'd have to get a look at the pan. Matt, I think we're going to need photos after all.

[qrn]

Ok, here are the directions from calaphon.

"

After each use, wash hard-anodized surfaces in hot, sudsy water using a nylon scouring pad - we recommend Scotch-Brite™ dark green scour pads. If you still see hazy or dark areas after it dries, scrub the dry pan (don't wet it) with a dry Scotch-Brite™ pad and rinse thoroughly. That often works best.

If the pan was used for frying or has baked-on grease or food, wet the pan, sprinkle Ajax®, Comet®, or Soft Scrub® with bleach on the surface, scrub it thoroughly with a Scotch-Brite™ pad and rise thoroughly."

Here is the discription of the recomended scotchbrite pad.

"Heavy Duty Scour Pad

For your most difficult tasks – both indoors and out. Use them to clean your most challenging kitchen messes, or anywhere you need abrasion"

I agree its sandpaper, as in "anywhere you need abrasion"

...I use it to sand finishes on various furniture I build...

It will not take off the anodizing I have used it many times. did not remove the anodizing...

Bud

[paulraphael]

I wouldn't use any scouring pad labelled "heavy duty" on any cookware. The sandpaper analogy is accurate; many of these pads have aluminum oxide abbrasives in them. This is essentially the same stuff that hard anodized surfaces are made from. They can eventually abrade through the anodizing. They're one of the few things hard enough to actually do so.

I wish the pad makers would be more clear about how abrasive these things really are. I see people buying them for doing the dishes all the time, and they wonder why it looks like their cookware was cleaned with a disk sander.

A softer pad with with a mild abrasive like ajax works well on all but the nastiest calphalon messes.

[Matt_T]

Interesting buildup theory. In any case, it sounds like nothing to worry about healthwise.

I use the ScotchBrite pads (the thin green ones. which have a "woolly" texture) on anodized pans with good results. For stubborn stains Ajax or Barkeepers Friend gives added oomph. These pans are pretty tough, steel utensils are no problem. Just whatever you do, don't use oven cleaner!!! (Speaking from experience)

[paulraphael]

Just whatever you do, don't use oven cleaner!!!  (Speaking from experience)

←

or dishwasher detergent, laundry detergent, or anything else strongly alkaline!

[prasantrin]

If you do send in the pan for a replacement, the company will send probably send you one of the Calphalon One pans since the commercial hard-anodized line is being phased out.

Speaking of which, Amazon has kick-a** prices on the commercial hard-anodized line right now. I picked up two 12-inch everyday pans and two 2-1/2 qt shallow saucepans (all come with lids) for only $70 (free shipping, plus when I checked out, my receipt noted a "buy 4 for 3" sale, so I wasn't charged for one of the cheaper pans). If anyone is interested in getting back-ups for their Calphalon commercial non-anodized, or buying some pots and pans as gifts, now would be a good time to pick some up.

Edited May 5, 2008 by prasantrin (log)

[Joy48]

I didn't need to pose my question, the answer was already here. I was boiling a couple eggs in my little Calphalon saucepot when I got distracted. Luckily I don't think it was on the heat for very long without water. There were white specs inside the pot on the bottom. After allowing it to cool I cleaned it with dish soap and a blue Scotchbrite and the spots came right off, but I still questioned the safety of the pot. I'm no longer worried about it. Thanks for the informative thread.