Is Tg responsible for the crispness loss of cereal based foods during storage ? | [Est-ce la Tg responsable de la perte du craquant des aliments a base de cereales pendant le stockage?]
1999
Roudaut, G. (Ecole Nationale Superieure de Biologie Appliquee a la Nutrition et a l'Alimentation, Dijon (France). Laboratoire de Physico Chimie et Proprietes Industrielles) | Dacremont, C. | Le Meste, M.
Many cereal based foods exhibit a loss in crispness upon rehydration above a critical value. This critical value is generally around 9-10% moisture. The aim of this presentation is to discuss the physical basis of this quality loss. First, the crispness loss was observed to occur while the products are still in the glassy state (i.e. below the Tg DSC or maximum in mechanical tan delta peak associated with the main relaxation process). Then, different aspects of molecular mobility within the glassy materials were studied. Sub-Tg relaxation processes in dry cereal foods and model systems were evidenced using dielectric and mechanical spectroscopies. Moreover, the influence of water content on the mechanical damping factor (tan delta) was studied at room temperature in bread samples and in starch-sucrose and gluten-sucrose mixtures
显示更多 [+] 显示较少 [-]