Mechanical action on the development of dough and its influence on rheological properties and protein network structure

Four simple dough preparation methods were proposed to imitate the rheological behaviors of traditional handmade doughs and the underlying mechanism was concomitantly elucidated. It indicated the hand-made doughs, including the conventional hand-made dough (CHD), bidirectional pressed dough (BPD), bidirectional rolled dough (BRD), unidirectional pressed dough (UPD), and unidirectional rolled dough (URD), showed weaker mechanical resistance than the mixer-made dough did. Compared with UPD and BRD, BPD and URD had better tensile resistance and deformation recovery. CLSM analysis showed that these two doughs also possessed smaller lacunarity (7.22-7.24 x 10(-2)) and larger branching rate (0.23 x 10(-2)), suggesting bidirectionally pressing and unidirectionally rolling could produce a dough with better gluten network connectivity. Analysis of gluten protein solubility showed that the stronger hydrogen bonds and hydrophobic interactions of gluten protein were derived in rolled doughs (URD and BRD), and the stronger slip caused by intermediate water in pressed doughs (UPD and BPD) may lead to the high gluten extractability. In addition, more disulfide bonds were formed in BPD (3.37 mu mol/g) and URD (3.62 mu mol/g), promoting the stronger mechanical resistance in BPD and URD. Nevertheless, pressing or rolling promoted no statistically significant increase in the content of glutenin macropolymers. Physical entanglement caused by the recombination of noncovalent interactions may be the main cause. In conclusion, the effect of manual external forces on dough quality was verified theoretically, and gluten network analysis can quantitatively evaluate dough microstructural changes.