THE SCIENCE OF SOUFFLÉS
Soufflé is an interesting dish, and a very versatile within its constrictions. The base of a soufflé is an egg white foam beaten to soft glossy peaks. This
base is the very reason that the soufflé rises in the hot oven. As you might now, gas has a tendency to expand its volume when heated, and that's what
happens with the air bubbles that are contained in the egg white foam. A slight disappointment is the inevitable sinking of the soufflé after we cool it
down (again, the firm law of gas properties), but this can be reduced to some extent by the way we make our soufflé.
Besides the base, a soufflé also contains the flavor! And almost any flavor can be used, from meat to fish to sweet desserts. Even if the most popular
soufflés are made from cheese or chocolate, any other ingredients can be used as long as the preparation is carried out properly. And that's what versatility
is all about! Whether you are an all-eater or a vegetarian, the soufflé is for you. The trick with choosing a good add-on to the egg white foam is to
include ingredients that will give extra moisture (for the growth of the soufflé), some proteins and starch or sugar (to make the air bubble walls more
viscous and stable), and of course the flavor that we desire. We cannot have too much or too little of each though. The texture of this aromatic mix is
important. The optimal way to prepare it is to have a mix that sticks together well but still can fall off a spoon without much trouble. Not too liquid and
not too soft, and often precooked (but not necessarily). That said, we can prepare this flavory mix with moist and protein- or sugar-rich yolks, purees of
meat, fish, fruits, vegetables, or sugar syrups. The popular ingredients like cheese and chocolate also provide proteins or starch that will make the air
bubbles stable. If you look through various soufflé recipes you'll see that they contain some of these ingredients prepared in a "sticky" and moist shape.
And frankly, you can make your own secret ingredient by following the above rules!
The proportion between the egg white base and the flavory mixture should be about 50/50.
When it comes to the very base of the soufflé - the egg whites - they have to be beaten properly, to soft peaks, moist (not dry) and shining. It is
important not to overbeat the egg whites to a dry mass that won't rise. At the same time, the foam must not be so runny that it rises so quickly it won't have
time to set in the heat before it spills over. Then, once we have our egg white foam, we need to gently fold it into the flavory mix. The word here is FOLD
SLOWLY not stir. That's because we don't want to destroy too many air bubbles. Before we fold in all foam at once, we can actually take a part of it (like
one third or so) and really stir it into the flavor mix so it becomes light and not too disruptive for the rest of the egg white foam that we fold in later.
So, what is so special with a soufflé? Probably the quickly rising mass that results from the heated air bubbles that expand their volume. Since the air
bubbles are surrounded by watery walls, the heated water will evaporate into the air pockets and also contribute to the growth of the soufflé. Now, as we
remove the soufflé from the heat, these hot gas molecules and water steam will cool down, and the water will condense back to liquid, so the soufflé will
shrink in size. Can this be avoided? No, but it can be reduced.
If we make a very thick soufflé, it will give more stability to its body and it will not shrink that much. However, it will not raise as much as a thin
soufflé either, so depending on our needs, we need to find a tradeoff between these two textures. Another factor that determines the look of the soufflé is
of course the heat. The higher the heat, the faster expansion of the air bubbles, but also the more dramatic fall!
Now that we have our soufflé mix, we need to bake it! First, we butter the dishes lightly (to make them easier to detach later on) and then we can coat the
dish with either sugar or some bread crumbs (to give the soufflé a crispy crust). Then, we pour in the soufflé mix, and we bang the dish a few times on the
table to make the mix spread out evenly. The baking temperature is about 170-200 C (330-400 F), with the lower temperature giving firmer interior as the
surface gets brown, and the higher temperature giving moist interior as the surface of the soufflé gets brown (and a quicker finish of course). The soufflé will also rise quicker in the
higher temperature. The interior is all about personal taste. Some people like a moist soufflé, when a toothpick stuck into it is still "dirty", and others
prefer a firmer soufflé when the toothpick remains clean. Experimenting with your own soufflé variants can be interesting and we encourage you to do that!