Thermal and Relaxation Properties of Food and Biopolymers with Emphasis onWater

Book chapter, 2017

In this chapter we are discussing the role of water for the thermal and relaxation properties of sugar solutions, food and folded biopolymers, that is, proteins. After an introduction to this research field we present, in Section 1.2, dynamical properties of sugar solutions and sugar-rich food. We demonstrate the common plasticizing effect of water and discuss the properties of the observed low temperature water relaxation. In Section 1.3 we focus on proteins and show the essential role of water for protein dynamics. We also discuss the debated origin and broadness of the calorimetric glass transition of protein systems. From studies of confined solutions, presented in Section 1.4, we conclude that the Gordon-Taylor equation cannot be used to predict the glass transition temperature of diluted aqueous solutions or bulk water. Finally, in Section 1.5, we are giving some concluding remarks about the role of water in biological and food materials.