What is the purpose of using potato peels for seasoning a cast iron pan?

Question

My first ever cast iron pan just arrived. The package contains following seasoning directions.

1. Wash with clothes detergent (not soap or dish detergent) to remove the rust protection coating.
2. Wash thoroughly with warm water to remove detergent. Dry pan.
3. Fill the pan with fresh potato peels. Pour sunflower oil or rape oil on them, until it is almost full with oil.
4. Leave the pan with the potato peels and oil for an hour on the next-to-highest setting on the stove top.
5. Throw away the potato peels and oil, dry the pan with kitchen paper
6. Coat the pan with a thin layer of sunflower or rape oil.

Not only don't I want to spend the afternoon peeling potatoes and then throw away most of them (I cannot eat the amount of potatoes needed for these peels), but even the positive amazon reviews for the pan all warn before the stench the charring peels produce during the seasoning: It lingered for about three days although I changed the fume hood filters, but it is a small price to pay for such a great pan. For me, it is a big price, because I have no fume hood, and there is no door between the kitchenette and the living room/bedroom. I looked up advise on seasoning pans, hoping for some trick, and found this question where the accepted answer doesn't include potato peels (in fact, no answer mentions them).

Now I am unsure whether to use them. On the one hand, I don't want to deal with the side effects. On the other hand, a producer is supposed to know what is best for his products. I don't want to get poisoned by an anti-rust coating residue that would have been rendered harmless in a chemical reaction with potato peels. Besides, I can't use the seasoning process outlined in the question I linked, because my pan doesn't fit in my oven.

I guess it would be easier to decide if I knew of their purpose. Does any of you know of using potato peels for seasoning pans, and can you tell me why they are needed? Or is it just an urban legend the ignorant manufacturer printed in the manual (the pan is not a well-known brand, maybe some hardware manufacturer decided it will be easy to add pans to their product line and made them without gathering enough know-how).

Asked by rumtscho

Answer

I personally had never heard of it, but after doing some research online, I found another set of instructions that called for boiling potatoes in the pan before seasoning:

After boiling potato peelings for 15 minutes, the skillet had a nasty slurry of grey looking sand in the bottom Once the skillet was heated, the pores were opened, and the starchy/water mixture was able to draw out oils and dirt that I was not capable of getting to through normal washing. I fully do not understand the science behind why the starch/water mixture did this, but the experience was enough to convince me of the need to do this. So much in fact, that I did this process twice on each skillet.

I read a few too many web pages while researching this, and didn't save all of the links, but I did notice a few things:

1. Some of the posts kept switching between saying cast iron and carbon steel; both are typically seasoned, but they're different materials, so I don't know if it's recommended for both, or if people were mixing things up. (I only have one carbon steel item, a wok, which I got second hand, so had already had its first seasoning).

2. Some of the posts mentioned boiling potatoes for 15 minutes, other mentioned frying potatoes as the first thing to be cooked in the pan (in oil), some mentioned cooking them 'til they burn. The boiling potatoes ones also mentioned it works for cleaning stainless steel pans.

3. Some mentioned peels specifically, others say that you can use any part of the potato ... if it's the starch that's of interest, I'd think the middle would actually be better, but I'm guessing that the peels were considered waste, and so considered a less valuable item; I'd be inclined to just use one potato, dispatched with a peeler, if you were trying to avoid wasting potatoes you weren't going to eat.

Answered by Joe

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