Impact of heat treatments on technological performance of re-milled semolina dough and bread

Re-milled semolina used for bread making is appreciated from consumers for its typical sensory features and nutritional attributes. Fluid bed drying treatment can be applied to semolina to change its bacteriological properties, to prolong shelf life by decreasing the risk of mould development, and to degrade some mycotoxins. The main goal of the present work was to evaluate the impact of heat treatment on structural development of semolina dough during mixing and leavening and on bread characteristics. Semolina was treated with fluidized bed drying at 90°C, 120°C, or 150°C for 5, 15 or 30 min. The heat treatment affected colour, moisture content, and farinograph indices of semolina. Results showed that the use of heat treated re-milled semolina significantly (P <0.05) affected the dough leavening kinetics and bread parameters such as crumb structure and mechanical parameters, in particular for treatment at 150°C for 30 min. On the contrary, after treatment of semolina at 120°C for 30 min, an improvement in the leavening phase of dough and no significant effects on bread quality were observed. Therefore, moderate heat treatment can be applied to semolina without having any negative impact.