The common industrial practice in bread making is to bake bread in an oven that is controlled at a constant temperature. Due to the oven structure, the bread effectively experiences four major temperature zones. On the other hand, temperature in each zone is the dominating factor on the baking mechanisms including gelatinisation, enzymatic reaction and browning reaction, therefore the final bread quality. This research aims to establish an optimal temperature profile for white-sandwich bread to achieve the best product quality. Experiments were conducted by a multi-level partial factorial design, where dough was baked in a process with 4 equally divided zones. Mathematical models were established to describe the effects of tin temperature and baking time on bread quality attributes. Based on the models, by solving a constrained minimisation problem, the optimal tin temperature profile for the lowest weight loss was determined to be {115 degreesC, 130 degreesC, 156 degreesC, 176 degreesC} in the four zones with a baking time of 27.4 min. The crumb temperature was predicted to reach 99 degreesC, while the top crust colour, side crust colour and averaged crust colour were all within an acceptable range. (C) 2002 Elsevier Science Ltd. All rights reserved.