Simplesse is a fat substitute derived from whey proteins or egg proteins, used in foods such as dairy products, condiments, margarines, and sauces. Microparticulated protein mimics the creamy mouthfeel of fat, letting manufacturers cut calories while keeping rich texture. Because it is protein-based, it cannot be used in frying, but in cold and gently heated foods it performs well. Its approval opened the door to lighter dairy desserts and dressings that still satisfied consumers. Later fat replacers built on its microparticulation concept for broader applications.