TEMPERATURE- AND MOISTURE-BASED MODELING FOR PREDICTION OF STARCH GELATINIZATION AND CRUMB SOFTNESS DURING BREAD-BAKING PROCESS

摘要

Temperature, starch gelatinization, moisture content and softness of bread define the formation of crust and crumb regions during the baking process. A computational model was developed to study the volume expansion, temperature profile and moisture content of the bread during the baking process. An arbitrary Lagrangian-Eulerian method was applied to describe mesh movement during volume expansion. Model predictions were validated with experimental measurements of bread temperature, moisture content and volume expansion. Occurrence of two distinct zones having different moisture contents, i.e., crust (<10%) and crumb (approximate to 39%), was observed. Extent of starch gelatinization and browning of the bread surface was also studied using earlier published kinetic model. Moreover, softness development for the bread crumb was also modeled based on the degree of starch gelatinization. This study concluded that apart from heat and mass transfer, inclusion of volume expansion in the model predicts more accurate bread temperature, starch gelatinization and crumb softness.