MODELING OF STARCH GELATINIZATION KINETICS OF BREAD CRUMB DURING BAKING

A mathematical model was set up to predict the extent of gelatinizatio n of starch in bread crumb during baking. A bread dough was placed int o a cylindrical steel mould and baked in a pilot forced-convection ele ctric oven at 250 degrees C. A type J thermocouple was placed into the bread crumb (i.e. at a depth of 22 mm in axial position) in order to measure the temperature. Samples were extracted at different final bak ing temperatures (60, 65, 70, 75, 77, 80, 85, 90, 95, 98 degrees C) an d the determination of starch gelatinization. kinetics was carried out on differential scanning calorimetric traces. It was shown that the e xtent of starch gelatinization follows first-order kinetics, where the rate constant varies with temperature according to the Arrhenius equa tion (K-o = 2.8 10(18) s(-1); E(a) = 138 kJ/mol). Kinetics were valida ted under dynamic temperature conditions: the experimental results wer e compared with those obtained from a mathematical model for heat and mass transfer during baking connected to the kinetic model for gelatin ization.