site banner

Small-Scale Question Sunday for January 1, 2023

Happy New Year!

Do you have a dumb question that you're kind of embarrassed to ask in the main thread? Is there something you're just not sure about?

This is your opportunity to ask questions. No question too simple or too silly.

Culture war topics are accepted, and proposals for a better intro post are appreciated.

2
Jump in the discussion.

No email address required.

If the pan is hot enough to say, sear meat, is that an issue?

Even if the chemical itself is stable (which AIUI is the root of the problem), is there a problem of the chemical leeching into the food?

First, the pan has to be ripping hot for that to happen and you will definitely smell the fumes. If you're already cooking with Teflon and haven't yet experienced any ill effects, I wouldn't worry about it. Even then, the problems it causes are temporary and not a chronic problem. With leeching, it's not so much that as it is flaking, as slick surfaces don't want to bond to anything including the underlying metal. But the inertness means that it's not reacting with your system, either, and should pass through without causing any harm. The problems caused during manufacturing are due to the precursor chemicals used in manufacture rather than the final chemical itself. Even if you're worried about Teflon, the pans should be the least of your concerns, since the same class of chemicals is used to coat a lot of food packaging (and other packaging) and is literally everywhere. The benefit of a good nonstick pan is well-worth the disadvantage of potentially marginally increasing exposure to a chemical that isn't known to be dangerous anyway.

The entirely reliable "compare the numbers in the first few google results" method says searing occurs at 150c / 300f and PTFE starts breaking down at 250c / 500f. That said, science is hard, interpreting things you don't know much about is hard, so idk. Reading the wikipedia article -

Most cases of polymer fume fever in humans occur due to smoking PTFE-contaminated tobacco,[62] although cases have occurred in people who have welded near PTFE components[62] or heated PTFE-coated cookware at 390 °C (734 °F) for at least 4 hours.[63] Teflon-coated cookware is unlikely to reach dangerous temperatures with normal use, as meat is usually fried between 204 and 232 °C (399 and 450 °F), and most cooking oils (except refined safflower and avocado oils) start to smoke before a temperature of 260 °C (500 °F) is reached

Going from "the gap is 150c / 250c, which seems fine", and then read "the gap is 230c / 390c, which seems fine", huh. (not that this proves or is even good evidence there is some sort of harm, but it is evidence it's quite hard to tell)

The abstract of a paper I skimmed, although the paper didn't seem that high quality:

PTFE is used as an inner coating material in non-stick cookware. This unique polymer coating prevents food from sticking in the pans during the cooking process. Such cookware is also easy to wash. At normal cooking temperatures, PTFE-coated cookware releases various gases and chemicals that present mild to severe toxicity. Only few studies describe the toxicity of PTFE but without solid conclusions. The toxicity and fate of ingested PTFE coatings are also not understood. Moreover, the emerging, persistent, and well-known toxic environmental pollutant PFOA is also used in the synthesis of PTFA. There are some reports where PFOA was detected in the gas phase released from the cooking utensils under normal cooking temperatures. Due to toxicity concerns, PFOA has been replaced with other chemicals such as GenX, but these new alternatives are also suspected to have similar toxicity. Therefore, more extensive and systematic research efforts are required to respond the prevailing dogma about human exposure and toxic effects to PTFE, PFOA, and GenX and other alternatives.

Summarized, "idk".

I've left a pan on max for four hours before, although it was metal, and was fine after cleaning. I'm sticking with metal pans.

TDLR is that for everyday cooking you're probably fine, but for blackening use cast iron?

Also I recall all the safety suggestions not to heat an empty ptfe pan.