I’ve only recently begun baking cakes with any seriousness and treated myself to some Magic Line pans to do so. A week ago, I was greasing a new 9x2 pan (it had been washed by hand but not used yet) with a stick of butter and when I took the stick away, the greasy wax wrapper had a greyish color in places. I thought maybe it had something to do with the wax paper itself, because the butter was not discolored, so I threw the wrapper out, baked my cake, and carried on.
Today, I greased two new 8x2 pans (again, prewashed by hand but unused) in the same fashion and when I pulled the butter stick away, where I had rubbed it against the pan, there was again the grey residue—this time on the stick itself.
As far as I could tell, the grey residue didn’t come off on my hands and didn’t transfer onto the cakes or the parchment lining the bottoms of the pans. When I washed the pans later, the towels with which I dried the pans did not come away discolored.
I’ve done some basic googling and saw some talk of grey residue coming off of aluminum pans like my Magic Lines being aluminum oxide. I frankly don’t know if that’s what was on my butter/wrapper, and I know there’s some controversy regarding how dangerous it is to consume anything with aluminum, but in whatever instance, I’m wondering:
1) Is what I’ve described a normal or common issue? How, if at all, can I avoid it?
2) Have I inadvertently poisoned myself, my family, and friends by eating cakes baked in these pans? (Or will I if I continue baking with them?)
I seem to be alive right now, so I don’t think the damage inflicted, if any, is instantly lethal, but obviously I’d prefer not to convert my tasty baked goods into time bombs… Or something like that.