Copper question - tin lining dissolves

[web-collage]

Recently I did a saute in grape seed oil and butter of breaded skinless chicken breasts in my heavy (2mm) French copper pan over easy heat. Added lemon juice at end of saute. Great chicken golden and juicy.

To clean the pan I soaked in hot water and soap then used Barkeepers Friend to clean tin lining and exterior copper. It looked like large areas of the tin lining on the bottom had disolved, leaving copper showing through. This was a fairly new pan with what looked like a good tin coating and I've sauted in it many times. No scratches in the tin.

Did the lemon juice dissolve the tin or what?

 

[Bigjim68]

I would hazard a guess that one of two things happened. Barkeepers friend is a mild abrasive, and excessive scrubbing of the tin would remove it. If you have cleaned it with BKF several times, you may have a cumulative effect. Or the pan was overheated. Tin melts at 450 degrees. If your heat did not go over 425, the tin would not have melted. If you noticed the copper before cleaning, probably was heat, after, I would guess it was the scrubbing.

Tin is used for lining because it is inert, and nothing used in cooking would melt it other than excess heat.1

 

[web-collage]

I let the BKF become a paste before using on the tin lining and so far nothing else has dissolved. If it was heat did the tin become one with my breaded chicken? Hard to tell what the temp was; burner on lowest mark. Did the lemon juice have anything to do with it?

 

[Andy M.]

The tinning could have been defective.

 

[web-collage]

Well rats, more work for Rocky Mountain Retinning. This is a nice heavy copper pan made in France, iron handle, my favorite for saute. But I won't cook in it with that much copper showing through.

 

[Robo410]

Is it a Baumalu Pan? (Alsace) their tinning can be rather thin. In the future: Tin will darken with age and use. Just because it has dark splotches does not mean it is not clean. Do not try to shine it up. Soak foods off and use a soft sponge or rag and hot soapy water only. Use bar keepers for the outside only. A properly tinned pan should last years before it needs retinning (like 5-10)

If it is a heat issue, the tin bubbles and you can feel where it has begun to melt. You can still saute, but omelets and crepe become difficult.

BTW, Rocky Mountain retinning does excellent work.

 

[GrillingFool]

Barkeeper's Friend has oxalic acid in it. Perhaps it isn't suitable for tin?

 

[web-collage]

No not Bamalu; I don't care much for their pans. This just says "Fabrication France" (in French) but has a nice curved shape and is solid 2 mm copper with iron handle. It's 9.5". There are no bubble blisters from overheating and close inspection makes me think it had a very thin tin lining. But who knows? My other copper doesn't seem to have thick tin linings. I've had two other (old) pieces retinned at RMR and can see brush strokes. This pan showed no marks at all. It was just such a suprise.

It is VERY hard not to clean that tin lining.

 

[web-collage]

Mostly I let BKF mix with some water and become a paste for cleaning the tin. It's also great for cleaning stainless steel pans.