black chef said:
i can understand your points, but the steaks were both at room temp. secondly, after placing the steak in the aluminum pan, i am able to crank the heat as high as i like WITHOUT generating more smoke... that is what i don't understand.
in the cast iron pan, because of latent heat & conductivity, i usually have to turn the heat DOWN 1-2 minutes after placing the steak in the pan... to decrease the amount of smoke.
the original discussion was cast iron vs. alum. my tri-ply clad cookware performs between these two extremes... giving me a good sear without an excessive amount of smoke.
This is interesting. We know that the greater the temperature differential, between the heat source and the heat sink, the greater the heat transfer. And we know that as the temperatures approach each other, less temperature is exchanged between the heat source (the metal), and the heat sink (the steak). I am guessing here, but it's and educated hypothesis, that the surface material shouldn't really factor in as much as the thermal mass of the material would. That is, the steak is a constant, and so will absorb energy at a given rate due to the moisture, fat, and intitial temperature.
I believe that the greater smoke is caused by the breakdown of fat due to an increase of available energy provided by stored heat. Let's examine the reasons why I think this is the case. First, both iron and steel are relatively poor heat conductors, at least as far as metals go. While aluminum and copper are great conductors. It takes more energy to heat the cast-iron and steel pans than it does the aluminum pans. But that extra energy is stored as latent heat. So when a steak is placed onto a hot aluminum pan, the amount of stored heat is less. The steak absorbs it as it cooks, and the burner adds more heat to the pan. Less of the available heat is transfered to the fat as it is absorbed by the steak.
On the other hand, the SS conducts better than does the cast iron, but again is lighter and is not able to store as much latent heat energy. It will be able to transfer more heat to the oil, as the steak is still absorbing the same amount of energy as it did in the aluminum pan. The result is more smoke.
Finally, with greater thermal mass, the cast-iron, once hot, has lots of stored energy to give up to both the steak and the oil (melted fat). Therefore, the cast-iron pan will create much more smoke than will either the aluminum or SS.
This principle is also seen in ceramic pots and brick ovens. They are slow to heat, and store very large amounts of thermal energy. They are also able to transmit that energy over a long time period to the foods and vessels placed in or on them. This is why a pizza stone is able to better cook the crust than is a light aluminum pizza pan.
One more thing, with the pans, conduction is the primary heat transfer medium. And so, surface contact plays a role as well. Raised edges on some grills can't deliver heat as efficiently as will complete contact with the entire meat surface. In fact, the grill marks represent the increased heat delivered by conduction than the more pale meat cooked by infra-red radiation from the pan surfaces that don't actually touch the meat. But the fat that drips into the valleys will smoke considerably by the time the meat absorbs enough energy to be cooked.
Whew. I think that is accurate.
Seeeeeya; Goodweed of the North