> wrote in message
oups.com...
> Hello,
>
> I inheirited a very black cast-iron pan from my mom. I enjoy cooking
> in it--it is very nonstick and it seems easy to clean by simply
> deglazing with hot water and scrubbing well with my regular nylon
> dish-cleaning brush. After each use, I dry the skillet thoroughly and
> apply a thin layer of canola oil. In fact, I'm a bit obsessive about
> this.
>
> My problem is this: I keep getting rust spots developing on the bottom
> of the pan. I can always remove them by scrubbing the spots with a
> mixture of salt and oil, but they keep coming back. Also, on the other
> side (the cooking side), it _looks_ like there may be rust _under_ the
> blackened patina. It's very hard to tell--it's not obviously dry,
> powdery rust like I get on the bottom, and the way that light reflects
> off the surface, the redness may be a figment of my imagination.
>
> I do not know how well the pan was treated before I got it, but I am
> guessing not very well. It was sitting in my parents' basement for
> years before I rescued it. They probably got it from my grandma, who
> was a notoriously bad cook.
>
> My question is: could there be rust _underneath_ the seasoning/patina
> layer? If there is, I think I'm just going to buy a new skillet, since
> it does not seem like it's worth it to remove all the seasoning, then
> remove all the rust, then reseason when I can get a new, preseasoned
> skillet for twenty bucks at Amazon.
>
always a dilemma.
One thing I would suggest is not to scrub with salt, it may well be the salt
which is causing the rust. The chloride in th salt combines with hydrogen in
the water to form hydrochloric acid which dissolves some of the iron forming
iron chloride, which hyrolyses forming iron oxide (the rust) and more
hyrochloric acid, ad infinitum. So, do not use salt. Nearly all my
pans/skillets are cast iron. I find I can use mild detergent and still
retain the non-stick surface patina, evindenced by the way the water forms
small droplets after rincing. I would say, like you, thorough drying is very
important.
HTH
cheers
Wazza