A mousse is a soft prepared food that incorporates air bubbles to give it a light and airy texture. Depending on preparation techniques, it can range from light and fluffy to creamy and thick. A mousse may be sweet or savoury.

Egg white is the clear liquid contained within an egg. In chickens, it is formed from the layers of secretions of the anterior section of the hen's oviduct during the passage of the egg. It forms around fertilized or unfertilized egg yolks. The primary natural purpose of egg white is to protect the yolk and provide additional nutrition for the growth of the embryo . Egg white consists primarily of about 90% water into which about 10% proteins are dissolved. Unlike the yolk, which is high in lipids (fats), egg white contains almost no fat, and carbohydrate content is less than 1%. Egg whites contain about 56% of the protein in the egg. Egg white has many uses in food as well as many other uses.