DisplayTitle

Molecular Mobility in Glassy Bread: A Multispectroscopy Approach

¹Laboratoire Biochimie Physico-Chimie et Propriétés Sensorielles des Aliments, Ecole Nationale Supérieure deBiologie Appliqée à la Nutrition et l'Alimentation, 1 Esplanade Erasme, F-21000 Dijon, France. ²Corresponding author. Phone: 00 33 3 80 39 66 64. Fax: 00 33 3 80 39 66 11. E-mail: roudaut@u-bourgogne.fr ³Laboratoire de Physique de l'Université de Bourgogne. Bâtiment Mirande Campus Universitaire, F-21000 Dijon, France. ⁴Wageningen NMR Center, Wageningen Agricultural University, P.O. Box 8128 NL 6700 ET, Wageningen, Netherlands.

The molecular mobility in low-moisture (<9%, web) white bread was studied as a function of temperature using pulsed-proton nuclear magnetic resonance (NMR), and dielectric and dynamic mechanical spectroscopies. The water was mobile, even in glassy samples. Different processes below glass transition temperature (sub-T_g) were observed, and a relaxation map of the studied system was drawn. These results have been interpreted and extrapolated to suggest that the T_g is not a universal predictive parameter for the physical stability of glassy food.