What is this rust-like stain on my aluminum pot, and how do I clean it?
Today I tried making Dulce de Leche from a can of condensed milk, using my aluminum pot as it's the biggest cookware I have.
However, after lifting the can, it seems to have left this circular, corrosion-like residue on my pot. Hot water and scrubbing with soap did not help, though it did reduce it slightly.
I did notice that the can itself became slightly rusted near the bottom. Is this rust? How do I remove this stain from my pot?
Best Answer
This will be from an electrochemical reaction between the can (mostly iron I think) and the water and possibly the aluminum (a better chemist than me would be able to tell you).
Aluminum has a fairly impermeable mono-molecular oxide layer on its surface (incidentally this is why you can color coke cans and the like; the color is in the oxide layer). The oxide layer in the case of your pot has probably been compromised by the reaction between the can and water, possibly scavenging some of the oxygen from this layer.
To remove this you can do either of some scrubbing with a steel based scrubber - basically polish the pot surface, or you might be able to remove it by boiling the pan with a weak acid solution; vinegar is probably the easiest, but any acid should do. Note that both will make the pot shiny, and you should do a short boil with some water to re-establish the oxide layer.
Pictures about "What is this rust-like stain on my aluminum pot, and how do I clean it?"
How do you get rust off aluminum?
To remove stains and discoloration from aluminum cookware, create a solution of 2-3 tablespoons cream of tartar, lemon juice, or vinegar per 1 quart of water and bring it to a boil. Soak your aluminum cookware in the solution for about ten minutes, and then use a soapy scouring pad to gently remove the stains.How do you clean badly stained aluminum pots?
Soak It. If the pan is deep enough, fill it with water, plus a few tablespoons of lemon juice or cream of tartar, says Varney. Boil 10 minutes and drain. This should lift the dark coating, which you can then sponge off with soap and water.How do you remove oxidation from aluminum pans?
Aluminum pans are quite common because aluminum is an inexpensive metal that is light and that transfers heat evenly. You might notice that the aluminum pan is developing black or dark gray marks on it. These marks are a natural byproduct of the aluminum oxidation process.Cleaning tarnished aluminum naturally
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