Glass transitions and product stability - An overview

Research since 1980 increasingly has shown that many fundamental food system properties ave affected by the presence of glasses and their corresponding low energy thermal transitions, i.e. glass transitions. This review discusses the theoretical basis of glass transitions in food systems and the relationship of glass transitions to polymer science. Food processes and attributes such as recrystallization, frozen storage, collapse, spray- and freeze-drying powder caking/clumping, starch retrogradation, and candy formation are all influenced by glass transitions. The role of water as a plasticizer figures predominantly in this discussion; An overview of experimental techniques available to the researcher to measure glass transitions in food systems will also be presented.