Scrubbed cast iron down to silver-- black gunk still won't come off!

I recently browned pork in my Lodge cast-iron skillet, and it left black, burnt spots over the pan (along with a few other places that arose from cooking over time). I boiled water in it in hopes it would lift it up, but it didn't. I scrubbed the spots down to silver (which I think is the exposed cast iron, where it was once black), but the black gunk is still there with the silver exposed around it. I can scrub it down to silver and it still won't lift. Help!

The black gunk feels smooth, and if I am able to scrape some away it's sooty. What can I do to get rid of this layer of gunk and get my cast iron back to normal? I don't want to re-season the whole thing with the gunk still on, and I need to use my pan again tonight for a big dinner with guest! I don't want to cause any more damage to it and am afraid to continue cooking in it!

Thanks so much!

nicole.lee
  • 78716 views
  • 23 Comments
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23 Comments

Woden
Woden March 30, 2023
There's all sorts of terrible advice in these comments.

1. Never use power tools or extreme heat to strip your cast iron. It destroys all monetary value of collectable pieces. Using wire wheels or sanders may make the surface too smooth for seasoning to stick. Burn off techniques may warp or crack your cast iron. Especially older, thinner, pieces.

2. Olive oil is not a quality oil for seasoning. It has a very low smoke point and will burn off easily. It also goes rancid easily.

3. Scrubbing with steel wool, brillo pads, or green scratch pads is fine. If you get down to silver metal, just reason.

4. Lye tanks and Electrolysis are the recommended methods to strip cast Iron.

"Cast Iron Cookware" on YouTube has some really solid care and seasoning videos. His cooking videos are awful. But he definitely knows how to care for cast iron.
 
Moondingo
Moondingo August 19, 2021
Oh lord have mercy, you did what to your pan? Ok so first of all I don’t know how people in the comments have scrapped it down to silver and not had a metallic flavor cooked into their food. That’s just bananas, secondly getting all the burnt off food isn’t necessary, that’s part of having cast iron. It’s like grill mats, you get burnt marks and if you try to use abrasive cleaning methods on them you ruin them. What I do is as soon as I’m done cooking I line the pan with olive oil and deep fry those burnt bits untill most of it comes off then wipe it clean with a wash cloth. If you really need to satisfy your chronic OCD they make little chain mail scrubbers, I don’t use them but it at least won’t take the finish off. God this made me cringe.
 
Moondingo
Moondingo August 19, 2021
Just to add grill mats isn’t a good comparison as one is Teflon and doesn’t need a season layer, but yea don’t scrub either one with abrasive materials.
 
Gumby
Gumby July 20, 2019
I've had a cast iron skillet for several years. I always seems to have had a small raised spot a little smaller than a lentil that constantly catches my spatula. I'm sure it wasnt burnt on food, but a raised metal spot in the pan bottom. I finally got so sick of it I put a grinding stone on my dremel tool and smothed it out. Now there is a bright silver spot about the size of a dime in the bottom of the skillet. I reseasoned it but the bright spot is still there. Will that be permanent, or will it eventually blacken?
 
candace
candace September 15, 2022
hi! did it ever go away? i did the same thing and am wondering myself. thanks 😊
 
Woden
Woden March 30, 2023
You polished it too far down. this doesn't leave anything for the seasoning to grip onto. If you want to fix this, strip the pan to bare iron. Allow it to rust heavily, strip the rust off and reseason. I'd personally leave it because a small spot is unlikely to cause issues. And allowing it to rust too much can destroy the pan entirely. But it's about the only option.
 
Alicia C.
Alicia C. September 12, 2015
You can also put it in the oven through the cleaning cycle. Bakes everything off the pan and then you can re-season.
 
Woden
Woden March 30, 2023
Doing this destroys all monetary value of collectable pieces, and risks warping or cracking your cast iron. Especially older, thinner pieces.
 
scruz
scruz September 10, 2015
when i was a little kid, my dad took a circular metal brush attachment for his drill to the insides of my mom's cast iron pan which surface had become irregular due to build up. it was beautifully seasoned and returned to that condition quickly as he smoothed out the cooking surface. it survived for many decades.
 
Woden
Woden March 30, 2023
This is not a recommended practice and it will destroy the monetary value of any collectable pieces. If you polish the cast iron too much seasoning will no longer stick to the pan.
 
Laura C.
Laura C. September 9, 2015
Hi Nicole,
This is Laura and I work for Lodge! I'd recommend that you use something very abrasive like steel wool to scrub the black bits completely off, then re-season your skillet. And since you'll be re-seasoning, go to town on that soap if you have to! Here's a quick video showing how to do that: https://youtu.be/Gg6S6vWyPH8

With cast iron, very high heat can cause things to stick, especially if there's little or no oil in the pan and especially if the ingredients are cold. Cast iron retains more heat than other pans, so medium/high heat is plenty high to sear meat, and veggies usually require low or medium/low heat. Here's another quick film on searing steak: https://youtu.be/7QmCVjSoY_w

Hope this helps!

-Laura
 
Richard E.
Richard E. May 21, 2018
You said to scrub the "black bits completely off" but, in the video you linked to, the pan is rusty and he scrubs the rust off while the black is still there so that doesn't match at all what you said. It doesn't come off, does it? I've spent hours scrubbing and using every tip I could find to get it off with no progress. When I soak beans, they turn black and this pot will eternally secrete that black gunk which is probably toxic. Do have it correct? How did you find this material that continues to exude black gunk presumably for years? And WTF is that black gunk? How toxic is it? How can sell a product like this? I am absolutely flabbergasted that you can continue to sell this product with being subject to a class action suit.
 
Richard E.
Richard E. May 21, 2018
You said to scrub the "black bits completely off" but, in the video you linked to, the pan is rusty and he scrubs the rust off while the black is still there so that doesn't match at all what you said. It doesn't come off, does it? I've spent hours scrubbing and using every tip I could find to get it off with no progress. When I soak beans, they turn black and this pot will eternally secrete that black gunk which is probably toxic. Do have it correct? How did you find this material that continues to exude black gunk presumably for years? And WTF is that black gunk? How toxic is it? How can sell a product like this? I am absolutely flabbergasted that you can continue to sell this product with being subject to a class action suit.
 
Babs2021
Babs2021 February 12, 2021
Hey Richard, I too have a very old iron skillet handed down four generations. There is so much burnt gunk on inside and outside. I am still trying to find someone that can help me. The best I could do was spray the entire pot/pan with oven cleaner. Place in kitchen garbage bag overnight. Scrub of a layer. Do again. I truly don't think the black stuff is toxic, but it certainly affects the color and taste. Good Luck!
 
Moondingo
Moondingo August 19, 2021
Put it on the stove till it starts to smoke, coat it with olive oil and switch to medium low heat until to but deep fry off. What doesn’t come off doesn’t need to come off. They are supposed to have some build up, that’s why old pans are so popular vs new ones.
 
Moondingo
Moondingo August 19, 2021
Until most of it*
 
ChefJune
ChefJune September 9, 2015
You're not supposed to scrub a cast iron pan. I don't wash mine. I clean it by applying a thick coat of Kosher salt to the pan while it's still warm. I use a pad made of sturdy paper toweling to wipe the pan clean. The salt acts as an abrasive, and as the pan cools, the "dirty" salt is easy to pour out and discard.
 
Jeri
Jeri September 12, 2015
I have put my iron skillet in a wood fire to burn off food. I never wash mine and to clean I use salt and always oil it after cleaning.
 
Babs2021
Babs2021 February 12, 2021
Hey Jeri, Does a wood fire get hot enough to take off decades of black gunk? Thanks!
 
Linda
Linda July 5, 2021
Babs: I'm 66 years old. My Mama always burned her cast iron pans in a wood fire to clean the build up from her pans. Then she would wash them and season them again. She would do this every winter since we heated with wood. She put one a day in the wood stove until they were all clean. This method of cleaning cast iron pans has been handed down from mother to daughter for hundreds of years.
 
Smaug
Smaug September 5, 2015
For the record; it's not appropriate for cast iron, but for non reactive pans (stainless, enameled, anodized etc.) burned on gunk is removed much more effectively by boiling water with a lot of baking soda in it than with water alone. Vinegar works too, but is expensive and reeks to high heaven- it doesn't work as we,ll either.
 
Susan W.
Susan W. September 5, 2015
Shelling is correct. As you cook, the seasoning builds up and eventually creates coating. Your pan will always have black on it that comes off. Here is a nifty little video that Amanda did a while back. You'll need to re-season your pan.

https://food52.com/blog/3547-how-to-season-cast-iron
 

Voted the Best Reply!

Shelli L.
Shelli L. September 5, 2015
Cast iron is not supposed to be silver. You have scrubbed off all of the "seasoning" that black gunk is supposed to be there it is a build up of oils that create a hard slick surface over time. It sounds like you need to re season the pan.
 
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