seasoning cast iron

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jjfortherear
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seasoning cast iron

Postby jjfortherear » Mon Jan 31, 2011 3:04 am UTC

lots of bullshit, might be the most bs ridden topic on the interwebs. from what I gather theoretically, and from my own experience, you've got to get the oil above its smoke point in order for any "seasoning" to happen (otherwise, you just warmed up some oil in a pan, then wiped it out). I don't really buy the "pores" in iron (I know it's pretty rough and uneven, probably even on an atomic level compared to other metals, but seems a bit too yuppieish a term), and this is what I've found from my own tests:

I took a pan, put it in the self clean cycle, washed and scrubbed the rust (fe+o2+heat=gg) off (with water, lol), dried it, coated it with bacon grease, wiped it as dry as I could with a paper towel, put it in the oven at 500 (smoke point of 400ish I think? well below 500 in any case) for about an hour, let it cool, repeated. As I did it more and more (about 15-20 times altogether) I got a little hasty and stopped lubing the handle and back, as they were dark enough for my liking, and didn't even leave it in for an hour at a time, or let it cool down after. I noticed it began to smoke within about 20 minutes, and since there was such an extremely thin coat of oil on it, it wouldn't smoke for more than a minute. After that, I figured there wasn't any more seasoning to be done, so I'd take the pan out and immediately wipe it down again (at which point it would smoke a little, but cool off enough to not smoke off all the new oil, thus requiring another 20 minutes or so in the oven). After the whole thing was over, I got a really nice, dark, dark red finish (probably from a little rust left over), and cooked some eggs. It was all I had ever dreamed it would be - didn't even need a spatula. but then...

I noticed some black crap all over my wrists. Tiny, flaky, black specks - I looked in the pan after I had cooked the eggs, and of course, the coating had begun to chip. I'm guessing this was because of how thin each coat was and perhaaaaaaps because I didn't let it cool, maybe also the initial coat didn't take well because of rust. I'd actually put that at the top of the list, since all the chipping was straight down to the iron (no chips half way deep into the coating). Anyway, let me know what you guys think might've been the problem, and please share your own experiences/success stories.

Also, I've just re cleaned that one and another one, and they've both got a glimmering coat of reddish on them. What would you guys suggest to use to remove rust and still be safe to eat off? Ideally not involving very high heat (or water, but that's a stretch).
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SU3SU2U1
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Re: seasoning cast iron

Postby SU3SU2U1 » Mon Jan 31, 2011 4:27 am UTC

Anyway, let me know what you guys think might've been the problem, and please share your own experiences/success stories.

Also, I've just re cleaned that one and another one, and they've both got a glimmering coat of reddish on them. What would you guys suggest to use to remove rust and still be safe to eat off? Ideally not involving very high heat (or water, but that's a stretch).


You've got the basic process right, coat a pan in oil, and heat the pan above the smoke point. The chemistry behind seasoning a pan is polymerization. Hence, drying oils are best. Unfortunately, I don't think any drying oils are edible? Any chemists out there might know better than I?

I generally use lard I get from a local butcher, but I can't see why bacon grease shouldn't work well. However, if you aren't getting a good coating, all that extra salt might lead to the iron rusting faster. If your coating is soft (can you scratch it with flatware?) use another oil or lard.

How are you cleaning it the seasoned pan? The best thing to do is to avoid rust all together- never clean a seasoned pan with soap, and use dry scrubbing as much as possible (salt works well as a coarse scrubbing agent). Never immerse it in water either.

You can remove the rust by coarse scrubbing, with steel wool, etc.

jjfortherear
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Re: seasoning cast iron

Postby jjfortherear » Mon Jan 31, 2011 12:30 pm UTC

Actually, flaxseed oil (drying) is what I had used originally (over this summer), and is the recommended one, but its smoke point is like 505, and I was only heating the oven to 500 (doesn't go any higher), so that was kind of a wash. Anyway, yeah, it could've just been the fact that the bacon oil was salty/peppery/etc, so hopefully this lard will work better. And lets say you get a nice, thick coating, with no more iron exposed at the surface - at that point it shouldn't matter whether or not you use soap, should it? The stuff (hard, polymerized oil), isn't going to dissolve in soap, is it?
Qaanol wrote:Actually this could be a great idea. See, you just have to bill the mission to an extrasolar planet as a mission, and then let all the fundamentalists from all religions be the missionaries.

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Coffee
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Re: seasoning cast iron

Postby Coffee » Mon Jan 31, 2011 1:35 pm UTC

All I know for sure is that Lodge says not to use soap. *shrug* They made the pan, I'll take them at their word on that.
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Velifer
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Re: seasoning cast iron

Postby Velifer » Mon Jan 31, 2011 2:24 pm UTC

I'll usually get an old pan from a garage sale or auction, surface rust is fine, but no big pits in the cooking surface. Then I'll take a wire wheel to it and take it down to good metal--clean it all up so it shines. After that, I'll wipe it out and coat it very very thinly with whatever oil is around, usually corn or canola. Then, heat it upside down in an oven (toss it in a 350º oven, turn it off and leave it). I don't usually go past the smoke point, it makes the kitchen stink.

After that, I cook in it. No high acid foods, it's a reactive pan. Clean it with soap and water like any other pan, dry it over a burner, wipe some oil in it and put it away.

A few months of this, and the pan is black and slick. A few years, and it's dishwasher safe. I use soap and stainless scouring scrubbers on mine.

If you've just cleaned one up, it will start to rust instantly. Just scrub the rust off with an oil-soaked rag.
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SU3SU2U1
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Re: seasoning cast iron

Postby SU3SU2U1 » Mon Jan 31, 2011 6:25 pm UTC

jjfortherear wrote:And lets say you get a nice, thick coating, with no more iron exposed at the surface - at that point it shouldn't matter whether or not you use soap, should it? The stuff (hard, polymerized oil), isn't going to dissolve in soap, is it?


Generally once it has a good coat it won't dissolve quickly in soap, but you are removing the oil from whatever you cooked in the pan. If you leave that oil, you'll keep building the coat. Alternatively, I guess you can clean it with soap, then rub it down with oil after washing, as Velifer suggests.

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Enuja
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Re: seasoning cast iron

Postby Enuja » Tue Feb 01, 2011 7:07 pm UTC

A friend of mine recommended this blog post. I haven't used it, but the advice seems generally sound, and scientifically based.

When I get black flakes on from my cast iron frying pan, it's usually because I haven't cleaned the previous food out of the pan well enough, and the black flakes are old, burnt food.

Also, at least according to Wikipedia, the smoke point of flaxseed oil is way below 500.

Because I don't have a kitchen fan in my current apartment, I haven't tried to re-season my cast iron frying pan. I just keep cooking on it, and it is reasonably non-stick. Not an even, perfect black surface, but it works.

jjfortherear
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Re: seasoning cast iron

Postby jjfortherear » Wed Feb 02, 2011 2:52 am UTC

yup, that's the blog from which I got most my theoretical basis. That's weird, I could've sworn flaxseed was higher...

EDIT: Ah, it's because she mentions she used avocado oil, which is 500 some, and had just been talking about flaxseed (guess I mixed up the two).
Qaanol wrote:Actually this could be a great idea. See, you just have to bill the mission to an extrasolar planet as a mission, and then let all the fundamentalists from all religions be the missionaries.

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Meteorswarm
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Re: seasoning cast iron

Postby Meteorswarm » Wed Feb 02, 2011 6:52 am UTC

I seasoned mine with plain vegetable oil, figuring that it was so highly refined that its smoke point would be very high, and that I didn't want it to smoke. This seemed to have worked well, but it's totally anecdotal. The pan was new.
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