Preparing sponge cakes with the warm method: my 2 cents

So, I finally made Victoria's cake. Be patient for the recipe, I'll post it as soon as possible! :)

For those who do not know, Victoria's cake is a typical Anglo-Saxon dessert. It is a sponge cake filled with strawberries and cream and sprinkled with icing sugar or, less frequently, covered with icing.

But Victoria's cake is only a pretext to introduce a topic that I have wanted to discuss for a while: the preparation of sponge cake with the warm method. I had already talked about it while making the white Sacher: the sponge cake batter can be worked warm. The procedure consists in bringing eggs and sugar to 45-50 C, and then proceeding with the whipping in the planetary mixer. The ingredients must be heated in a water bath (bain-marie). In general, direct contact with heat is not recommended.

This procedure allows to incorporate more air and to stabilize the mass more quickly, compared to the cold whipping. Can we then conclude that preparing sponge cakes with the warm method is far better? It depends. With the warm processing, more air is incorporated, which means a drier final product. In short, it depends on what you have to prepare, whether the sponge cake will be soaked with syrups or not, and so on.

What I was wondering was why the heat favoured the stabilization of the mass and here, I tell you, my speculation / interpretation of the phenomenon starts. Yes, because looking everywhere, no one gives precise explanations. Di Carlo, too, doesn't go into too much detail in his book. The only explanation I have given myself is that the heat denatures the proteins of the eggs. The different configuration could allow proteins to bind air more easily and stabilize the mass. After all, it is very similar to the procedure for obtaining Swiss meringue.

Does anyone have any ideas or precise references? Let me know in the comments! :)