What are the reasons for sauteeing with fat?

Question

I know it's a basic question and of course it's what I do every time I cook. But I'd like to know in depth what the reasons are and the detail of how it affects heat transfer and chemical changes in food.

Answer 1

When you're sauteing something, you want it to heat up quickly, so you put it in contact with a hot piece of metal. However, the food is not perfectly flat, so there will be a few contact spots and lots of pockets of air in between. This air acts as a very good insulator, so you will end up with a piece of food that is very unevenly heated.

If, on the other hand, you add some fat, this will 'fill in the cracks' and provide a more even heating of the foodstuff. (Fat does not conduct heat as well as metal, but much, much better than air.)

Also - fat tastes good.

Answer 2

Lubrication and flavor is your answer. I learned a steam sauté technique working at a French spa restaurant which was just like sautéing in butter, but with stock instead.