Which component is crucial for a mousse’s texture?

The texture of a mousse is significantly influenced by the incorporation of egg whites. When whipped, egg whites create a stable foam that adds lightness and airiness to the mousse. This aeration is key to achieving the desired fluffy and creamy texture characteristic of mousses. The delicate structure of the foam helps provide volume and an elegant mouthfeel, essential for a well-made mousse.

While other ingredients can play a role in the overall structure and stability of a mousse, such as gelatin providing additional firmness or butter contributing to richness, the fundamental quality of the mousse's airy texture derives primarily from the whipped egg whites. This is why egg whites are considered a crucial component in creating a successful mousse.