Effects of pressure in hand kneading and mechanical bionic kneading on dough formation and texture properties

In order to explore the influence of pressure on dough texture properties during hand kneading and mechanical bionic kneading, the pressure distribution of dough was characterized by numerical simulation, the changes of dough moisture distribution, protein secondary structures, gluten network development, microstructure and texture properties with development of resting time were investigated. For mechanical-bionic-kneaded dough, pressure level and compression ratio were greater than those of hand-kneaded dough. The increase in pressure level was beneficial for the unfolding and orientation of protein molecules in the dough, allowing more sites to form hydrogen bonds, and thus improve the content of β-sheet and α-helix structures. The maximum values of β-sheet and α-helix contents in mechanical-bionic-kneaded dough were about 10 % higher than that in hand-kneaded dough. This made continuity and uniformity of gluten network structure, combination degree of gluten network and starch granules, and resilience of mechanical-bionic-kneaded dough were better than those of hand-kneaded dough. The best conditions of mechanical-bionic-kneaded and hand-kneaded dough occurred at 30 min and 45 min of resting time, respectively. High pressure during kneading could promote the formation of gluten network, the dough resilience and shortened the resting time required for dough to reach a stable state.