Molecular Organization and Topography of Prolamin Protein Films

Abstract

One of the promising nonfood applications of zein and wheat gluten (WG), two prolamin-based proteins, is in the packaging area. Advances in microscopy and imaging technologies allow the development of biodegradable prolamin protein-based films that are functionally tunable. The functional properties of the prolamin films are strongly influenced by the molecular organization of the proteins as well as the surface topology. Atomic force microscopy (AFM) can provide such information, especially the surface topology along with understanding of film formation mechanism of the proteins. Confocal laser scanning microscopy (CLSM) on the other hand is widely used to visualize the distribution and molecular arrangement of protein components in the prolamin films. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) provide high-magnification images of the microstructure of the films. In addition, some specific chemical bonding interactions can be accessed by infrared (IR) spectroscopy. This chapter reviews the recent studies on prolamin films that were investigated using imaging technologies, coupled with other techniques to evaluate the effectiveness and properties of these biodegradable films. The rich information gained from imaging technologies is useful for prolamin protein film production, especially zein protein and WG protein for packaging applications.