**2.3 Protein-based coatings**

Proteins generally occur in the form of globular proteins or fibrous proteins. Fibrous proteins are insoluble in water and generally play the role of a basic structural element of animal tissues, they are also soluble in aqueous solutions of salt, bases or acids and perform different activities in living systems. Various types of globular proteins such as corn zein, whey protein, wheat gluten and soy protein are involved in edible coatings/ films. A dispersion or protein solution is taken into consideration to create coatings and films, and the solvent that is taken into consideration for playing this role is generally restricted to ethanol water combinations, or simply water or ethanol.

Protein-based coatings which include the use of casein, gluten and soy protein serve as good oxygen blockers and thus help preserve the food products from any deteriorative reactions. Proteins are reported to impart good mechanical properties and gas barrier properties.
