On Food And Cooking
The Science and Lore of the Kitchen
by Harold McGee

This book discusses all the major food categories, from meat and potatoes to sauce bearnaise and champagne. Topics include:

Why can cream be whipped but not milk?
Why do we cry when onions are chopped?
Does searing meat near a high flame seal in flavor?

IB says: "The chemisty of ingredients and cooking folks. A seriously good read for the serious culinarian."