The science of a souffle
The ability to create a perfect souffle is often the hallmark of an accomplished chef or baker. For this reason, many are intimidated by the light and airy pastry. However, with a basic understanding of the underlying scientific principles that make a souffle what it is, you can be sure that your next attempt will go off without a hitch.
Its all in the eggs
A souffle is essentially made of two parts: a base and whipped egg whites. The base can be anything, from just egg yolk to a sweet chocolate sauce. Sweet or savory, the base is what gives the majority of the flavor to your souffle, while the egg whites provide structure. Of course, you can add more flavor with an accompanying sauce, but the basic egg white and base formula applies to any souffle.
Fat and protein
The most important thing you can do when making a souffle is cleanly separate the egg yolk from the whites. An egg yolk is composed of fat along with some protein, while the white is all protein. When you whip egg whites, you are encasing little bubbles of air in protein skins. The presence of any fat at all will cause the bubbles to collapse, and your egg whites will lose all their structure. As such, take extra care when separating out the whites to be sure that there are no yellow bits floating around in them. If there are, be diligent about fishing them out or simply start over.
Whip until dull
Once you have separated the yolks from the whites, it is time to whip the latter into a thick foam. Make sure the mixing bowl you are using is as clean as possible, and using a wire whisk, begin to break up the whites. Then you can begin whipping in a clockwise motion, incorporating as much air as possible. The best way to tell when the whites have been sufficiently whipped is to watch for them to lose their sheen. Once the mixture has become dull, you are ready to incorporate the whipped whites into your souffle base.
The final key to a perfect souffle is not to overmix the whites into the souffle base. Gently fold just long enough until all white streaks disappear. When you bake the mixture, the air in the bubbles will expand, causing the souffle to rise. In addition, the protein and any fat that was in the base will harden to provide support to the overall structure.