Soufflés are quite finicky to make and require a great deal of attention to detail while preparing them. One tiny mistake can ruin the whole soufflé and make it collapse.
A soufflé has two main components: the base and whipped egg whites.
The base- a soufflé can literally be made by using an egg yolk as a base and folding it into whipped egg whites. The only problem is that it would lack flavour and also would rapidly collapse as soon as it is out of the oven. To stabilise the structure of the soufflé, we use flour or cornstarch.
A soufflé can be either sweet or savoury, and the base determines this. One can make an apple soufflé by cooking down apples to a very thick paste and then adding a bit of flour to create a stiff thick paste. But note that flour reduces the original flavour and hence should be used sparingly. You can make a savoury cheese soufflé using creamy cheeses like Brie, Gorgonzola, Camembert etc or hard cheeses like cheddar, Parmesan etc. A trick to retaining volume when using a hard cheese is to finely grate it to crest the base instead of melting it. When you melt the cheese, oils are released and it interferes with the whipped egg whites and reduces the rise of the soufflé. But when you grate the cheese, the cheese is still spread evenly throughout the soufflé but it doesn’t interfere with the whipped egg whites as much because by the time the cheese melts and releases its fat, the egg whites have already risen and stabilised.
Whipped egg whites- it is the whipped egg whites that are responsible for the beautiful rise of the soufflé. Soufflé is derived from the French verb souffler which literally means “to blow up” and indeed that is what occurs in the oven when the air trapped in the whipped egg whites turn to steam and makes the product as light and fluffy as a cloud. But to achieve this, care must be taken so as not to introduce any trace of fat to the egg whites. Fat weighs the air bubbles in the whipped egg whites down and causes the soufflé to collapse. The trick in these cases is to encapsulate the fat in a thick starch based sauce so that it doesn’t reach the egg white proteins at all, and hence does not cause any collapse of the soufflé.
Encapsulation of fats can be achieved through many different ways. The easiest way is to use a very stiff, almost solid, starch thickened sauce to surround the fat. A mixture of cocoa powder and cornflour is very suitable for chocolate, while corn- flour on its own is acceptable for cheeses. There are two methods that can be employed, either add the solid fatty ingredient in a finely grated form to a nearly set sauce, or add the fatty food to the hot sauce and beat really hard while the sauce cools to divide the fat into fine droplets that solidify and are coated by the sauce.