ABSTRACT
This chapter reviews the characterization by calorimetry of thermally induced conformational changes and phase transitions in pre- and postextruded cereal flours and the use of calorimetric data to elucidate the macromolecular modifications that these materials undergo during extrusion processing. It demonstrates the use of calorimetric data as a tool to evaluate the impact of formulation, processing, and storage on end-product attributes. Extrusion processing is widely utilized in the food and feed industries for the manufacture of value-added products. Differential scanning calorimetry (DSC) is a thermal analysis technique that detects and monitors thermally induced conformational transitions and phase transitions as a function of temperature. With DSC, the glass transition is observed as a sharp decrease of the heat capacity on cooling and a sudden increase in heat capacity on heating. The glass transition temperature indicates a change in the mobility of the molecular structure of materials.
