ABSTRACT
Food proteins come in a variety of conformations with the three major structural features being random coil, fibrous (rigid rod), and globular (Figure 7.1) (Belitz et al. 2009). The molecular structure adopted by a particular protein depends on its amino acid sequence, prevailing environmental conditions, and history, for example, exposure to different temperatures, pH values, ionic compositions, and solvents (Damodaran 2007). Proteins tend to adopt a structure that minimizes the overall free energy of the system, provided there are no kinetic constraints (energy barriers) that prevent them from reaching the lowest energy state. In many food applications, proteins are trapped in a metastable state.
