Today was the day to test some new cake recipes, and that made me wonder: why is the cake only good when it’s fluffy?
Here, there is no point in associating the gluten network formed during the opening of the bread, which aims to hold all the gas released by the natural yeast, even because the flour contained in the cake dough is not beaten to the point of forming the gluten network; it is also not worth thinking that it is the egg white that gives aeration to the cake, because it is not… so I wonder, what makes the cake so fluffy?
First of all, let’s think about egg whites, which we always recommend aerating them well and adding them delicately to the dough… you know what, BOBAGEM! But calm [!], before anyone decides to call me an inconsequential scientist, I’ll explain!
THE egg white it has two proteins, albumin and globulin, which are also present in milk, beef blood, wheat and meat. These proteins have a foaming property influenced by pH (acidity), temperature and the presence of other components of the medium, such as sugar, for example. However, if we compare the foam formed by milk and egg white, we will see that they are different, this is because milk has a lower concentration of these proteins and consequently less foam, have you thought about that cappuccino froth?
But let’s just think about the egg white, used in the cake. When we hit this egg whisk on the mixer, or fouet or fork or any object that helps its aeration, it undergoes a physical modification, that is, at the beginning, the protein is a complex all rolled up, as if it were a ball of wool, when we apply it a physical force in this complex, it unfolds and involves air. As we hit, the air bubbles get smaller until they completely decrease and denature, causing air to no longer be incorporated and our clear to release water. Did you remember that last time you went to make a cake and beat the egg white so much, wanting to make it very fluffy, and in the end, incorporated what you thought of as “egg whites”? Well, make no mistake, you simply smashed all of your protein to the point of denaturing it and separating all the water present in the egg white. That is why it is ideal to adjust the beat time with the ideal size of the air bubble – so, when a recipe gives the beat beat specifications of the egg whites, it is better to follow to the letter.
But even if that egg white is beaten with great effort, the film that involves the air bubble is so delicate, that when we incorporate the egg white into the cake, this bubble bursts, not only with the movement – however delicate it may be – as also due to the weight of the dough, which takes flour, fat, sugar … The volume of the dough obviously increases, doubles in size, because even though some bubbles burst, the incorporated air, which causes the white to double its volume, will also make with the dough to double. But between the light mix here, throw dough over there, rest a little while the oven is not at the right temperature and throw the baking sheet into the oven, most of that incorporated air is lost. And then I ask, and now José?
The savior comes in, our so-called Royal yeast takes over and saves our cookie from collapse! Yeast, as we know, is responsible for the growth of the dough, but since no dough in the universe comes out of nowhere, what it does is simply release gas and increase the hollow volume inside our product. This gas formed during the cooking of the cake is retained when the protein present in the egg white rises to the surface and coagulates, that is, it forms the cake’s shell, a physical barrier … that hard shell that everyone thinks is cooked flour! Or have you never heard your grandmother say, “Damn, I put too much flour in the time to grease the pan!”.
If the egg white made all this yeast work, it would be a mystery to discover why the box cake is so fluffy, when it is not necessary to aerate the egg to incorporate it into the powder. Even because in the industrialized cake dough there is no secret, it is flour, yeast and sugar, nothing more!
Now, if we add sugar to the egg white, then the conversation is different. Bergamo’s swiss roll, for example, takes yeast, beaten egg whites with sugar. What sugar does in the clear is to create an aerated system that is much more stable and strong, that is, the bubbles don’t burst so easily, which is why its mass is so fluffy, as if it were an edible cloud. What also happens in the Angel Food Cake, that cake made only of egg whites.
If anyone wants to prove the theory, I propose a simple test:
1. With industrialized cake, try to beat the egg whites for one preparation and for another simply mix everything by hand. Bake and check the aeration difference.
Now it is clear that we cannot forget our dear sponge cake, which does not take any yeast, but has a clear face, and no sugar to help in the stability of the foam! And it grows, which is wonderful! The real reason is that the sponge cake dough does not carry fat like the others, basically it is egg and flour, nothing more; therefore, a lighter dough can withstand greater air incorporation, and here, there is little care in the movement – the less air bubbles burst, the more fluffy your sponge cake will be.
Who made the cutest cake in history? Xiii, it will be a war between grandparents from all over the world to find out … I can even imagine!