How to Boil an Egg
September 3rd, 2008The most interesting fact I learned today, is that eggs get cooked as a function of temperature, and not time - which means that boiling an egg for about ten minutes is actually the wrong way to cook your egg. Cooking for Eggheads, featured in Discover Magazine, has the details.
Recall that when an egg cooks, its proteins first unwind and then link to form a rigidifying mesh. But not all its proteins solidify at the same temperature. Ovotransferrin, the first of the egg-white proteins to uncoil, begins to set at around 61 degrees Celsius, or 142°F. Ovalbumin, the most abundant egg-white protein, coagulates at 184°F. Yolk proteins generally fall in between, with most starting to solidify when they approach 158°F. Thus, cooking an egg at 158°F or so should achieve both a firmed-up yolk and still-tender whites, since at that low temperature only some of the egg-white proteins will have coagulated.
The gastronomic experience varies widely with the actual temperature at which the food is cooked. Understanding protein chemistry could possibly improve the experimentation process that is carried out in my kitchen in the name of cooking.
