I have a collection of cast iron pans that I have assembled since coming back to America eleven years ago. I had to learn all about cast iron pans and their care in the time since then, and doing so has been a scientific and culinary adventure. I also have delved into the religion of Cast Iron Pans, which is the myth of weather or not to use soap on the pans to clean them. My wife was not too excited about cast iron, especially when she found out I was following the no soap regimen for cleaning. But it was what everyone seemed to say, both in person, and online. There was only a small faction that would advocate the use of soap on the pans, but they could not possibly be right against the throngs of people who strongly advised not to. Could they?
The real revelation for me came when I looked at a skillet one day, and realized how dissatisfied I was with the build up of seasoning that had cracked and was becoming dislodged from the pan, exposing metal beneath. I took that pan out to the workshop in a desperate bid to make it right, and began every method I could think up to try to remove that thick coat of seasoning, and settled in on simply sanding it down to bare metal. What I ended up with was a shiny silver pan. By this time I had already experimented with washing the pans with soap a few times, and one thing for darn sure, I had never seen soap take the pan down to this! As it turns out, cast iron is actually a very shiny silver color on its own!
After I finished stripping the pan down to my satisfaction, I smoothed out the bottom and blew it off with the air hose, then took it to the sink and washed it thoroughly. Then I put it right onto a hot stove to evaporate any water and keep it from rusting. Then I coated it with olive oil, and put it in a hot oven, about 450 degrees, and left it for the better part of an hour. The pan was blackening up again! I repeated this step three times, and the pan had not only blackened but the bottom inside was as smooth as glass, and looked better than it ever had new.
One thing I can attest, soap washing most definitely does not strip off the seasoning from the pan. It does dull it, but since I always freshen up the seasoning a little after washing, that is no big deal at all. It is perfectly fine to wash it in soapy water! Revelation! And Missus is happier to see it being done. I am also the wiser for this knowledge, because I know how to not only repair, but improve my Lodge cast iron pans, to make them more like Finex pans, which are far more expensive, but have a more refined finish out of the box.
Mostly, I am happy to have a better understanding of he science of cast iron pans, and that oil, when heated to the surface, causes polymerization, which is when the oil turns into a plastic coating, protecting the pan, and giving it an excellent non-stick quality. Yup, those old pans are really more of a plastic pan on an iron base, or an iron pan with a plastic coating.
Now, having said all that, there are some folks who will never put soap on their pans. It was the way they were taught, and they will not bend on the rules they were raised with. Those rules work for them, and have always worked for them. Momma said it, and they believe it, and that is what they are sticking to, pardon the ironic pun(s). It stems from an evolutionary trait that when we find things that work and are safe, we tend to rely on those things to keep us safe.
It is another irony that the evolutionary trait I just described is also why some people have a cast iron resolve against the Covid vaccine.