What's Hot, What's Not, in Pots and Pans
That's the title of a 2008 New York Times piece by Harold McGee, author of the invaluable "On Food and Cooking." He tested the conventional wisdom about the virtues of different materials in cookware and found that they don't actually behave as many people believe.
The complete article is here:
Briefly, he found that cast iron is not an even conductor of heat on the stovetop. (It is in the oven.) He measured a consistent difference of 100° F between the center and rim of a "medium sauté pan," whether over flame or an electric heating coil. Low heat causes "even browning over a small area at the center of the pan, and none elsewhere." The most even distribution of heat was with heavy copper lined with stainless steel, and two inexpensive aluminum pans with nonstick coatings. In between was stainless-clad aluminum, which was also pretty good. Not so the cast iron.
He also found that all materials, not just cast iron, became more non-stick as they were seasoned by repeated use without scouring them down to the metal. People sometimes ask here whether stainless steel needs to be seasoned. According to McGee's experience, it's a good thing.
There's other information and more tips in the article - well worth reading. He concludes, "So what to do about getting pots and pans that work best? Choose the ones that you like, for their heft or their lightness, for cachet or economy, for finickiness or ease.... And cook with them often." Sounds good to me!
It all depends on what your trying to cook, what you have to cook with, and the chef's skill.
In some parts of the world, chef's can cook a great meal on an old school metal hub cap over charcoal. While others can't use Falk/All-Clad/etc. on a modern gas/induction/electric stove to save their life.
Harold McGee has a bunch of good books about the science of cooking. "Conventional wisdom" really depends on which population you are talking about as different groups have different conventions, and one's groups conventional wisdom can/will contradict another groups (especially if they are doing very similar activities, but have very different end-goals in mind).
I doubt that he was really surprised in 2008 that cast iron is a bad conductor and cast iron cookware produces uneven heating over the bottom of a large skillet or saute pan (actually that any of his experimental data or conclusions were a huge surprise either) - it is probably more a literary device to get those gosh darned readers to think that he is a regular kitchen schmoe like them, making them more receptive to his cooking-geek knowledge.
His article is a good read, and the explanation about Bénard-Marangoni convection is pretty sweet. You might consider some of his cookbooks.
Pretty good article. Thanks for the link--I was surprised I hadn't seen it before.
It is quite short on details and numbers. And it omits any real analysis on responsiveness--a water boil test on MAX heat isn't very informative.
But if the takeaways are: (a) cast iron is slow and uneven; and (b) all surfaces benefit from "seasoning", and that message finally gets across, I'll be happy.
It would be great if those two messages got across. To me the major benefit of most CI is weight/thickness. If you get it good and hot and drop a steak on it the temp will drop but not like it would with a thin skillet made of most anything. But for that very specific application I have come to prefer a very heavy well seasoned steel pan. My big take away is that for many applications the weight/thickness is just as important as the material ( within my unreasonable limits, of course). The big steel pan in the photo is 14". Sure it is heavy, being about 3.5 mm, but with the nice French handle it is easy to maneuver. A typical CI pan of that size and thickness with its four inch handle would be unworkable for my 64 year old wrist.
:) Al/SS is not the most popular construction, but I think most people can deduce that Al/SS has proximity the same heating distribution as SS/Al/SS, but better heat response -- assuming the aluminum layer is the same thickness. Of course, Al/SS construction often has even thicker aluminum, so the heat distribution will be even better.