Ok, we’re about to nerd it up here because I’ve been reading some information on the science behind seasoning cast iron that kind of blows my mind. It was just last week that I was patting myself on the back for having a cast iron wok that nary a kernel of fried rice stick would stick to, and this week I discover I have been seasoning it all wrong. I did suspect that I was re-seasoning a little more often than I should, and I tried to ignore a streak of rust here and there that would come and go–but all of that has been explained by Sheryl Cantor on her blog. I’ll summarize for you, but you really must head over and read the whole thing:
It does matter which oil you use, and flaxseed oil is recommended because it’s a “drying oil” (not what you think) and will create a hard coating.
Yes, flaxseed has a lower smoke point than the peanut oil I’ve been using and yes, that means it will start to break down faster–release free radicals!*–and yes, it’s still what Sheryl recommends. (It’s not like the peanut oil wasn’t smoking when I seasoned my wok, but it never occurred to me that I should have been more…aware of the free-radical part.*) The reasoning and the recommended process are detailed in the original post.
Red rust is bad (duh, we knew that…sheesh.) but black rust is good (…eh…?!) which Sheryl covers in another post on that subject, complete with chemical symbols and smart commenters that have sold me on the whole thing.
The pictures on her posts alone have convinced me to strip down my wok and start seasoning from scratch. Anyone else?
*Updated to include a little disclaimer. Let me be clear, I am in no way advising you to set off a bunch of free radicals in your kitchen, nor overheat your pans that are doused with oil. I hope I made it clear at the beginning of the post that I actually have no idea what I’m doing in this area, which is why I’m pointing you to someone who seems to. Proceed with caution, at your own risk, etc. Only follow my lead when I tell you to splurge on good wine, never to buy fresh tomatoes in February, always give the best piece of food to the person you love, things like that.