Explain Foaming Properties of proteins
To understand the foaming properties of proteins, we need to know some basic aspects of foam foods. Foam foods are usually colloidal dispersion of gas bubbles in a continuous liquid or semisolid phase that contains a soluble surfactant. (Surfactant is a chemical compound that acts as a surface modifier which reduces the surface tension of the liquid). A large variety of food foams produced with proteins, exist with widely differing textures, such as cakes, whipped creams and toppings, ice creams etc. In many cases, gas is air (occasionally CO2) and the continuous phase is an aqueous or suspension containing proteins.
Next, what are the properties basic to proteins, to be a good foaming agent? A protein must:
- be able to rapidly absorb at the air-water interface during whipping,
- undergo rapid arrangement and rearrangement at the interface, and
- form cohesive viscoelastic film.