Abstract: The present invention primarily concerns a process for producing a plastic material, comprising the steps (i) providing a corn gluten source and a first liquid phase comprising an organic solvent; (ii) extracting solvent-soluble components of the corn gluten source into the first liquid phase; (iii) precipitating a first fraction of the solvent-soluble components out of the first liquid phase, resulting in a second solid phase including the first fraction of the solvent-soluble components and a second liquid phase including a second fraction of the solvent-soluble components; (iv) separating the second solid phase and the second liquid phase; and (v) recovering a flexible plastic material from the second liquid phase or recovering a hard plastic material from the second solid phase.