Interrelationships of protein composition, protein level, baking process and the characteristics of hearth bread and pan bread

Baking performance of hearth bread and pan bread were investigated using 10 wheat varieties with variable protein quality. For most varieties, samples were selected at two protein levels, approximately 11 and 13% (d.m.). The effects of flour quality on loaf characteristics were different for hearth bread compared to pall bread, where both protein quality and protein conten t affect loaf volume positively in an optimised baking test. Hearth bread i s more complex as both the form ratio and loaf volume are critical external characteristics. When using fixed proving time, the form ratio was positiv ely affected by dough resistance and mixing peak time at high speed mixing, and negatively affected by dough extensibility. Dough resistance and mixin g peak time correlated strong it to the HMW glutenin composition, whereas d ough extensibility was related to protein content. In contrast to the form ratio, loaf volume was positively affected by dough extensibility, whereas protein quality had no significant effect. This was seen both for doughs pr oduced at optimal mixing time at high speed mixing: (126 rev/min) and for d oughs produced at fixed mixing times at low speed mixing (63 rev/min). When proving time was optimised to achieve a defined form ratio, flours of stro ng protein quality should be proved longer than flours of week protein qual ity, resulting in higher loaf volume for flours of the strongest protein qu ality. With respect to protein content, the positive effect of protein cont ent on loaf volume was counteracted due to reduced proving time when aiming for a defined form ratio. (C) 2000 Academic Press.