Behavior of semolina, hard, soft wheat flour dough at different aging times and temperatures through LAOS properties and molecular interactions of proteins

Abstract

Changes in large amplitude oscillatory shear (LAOS) were used to compare the dough strength and resilience during aging at 4 °C and 25 °C for hard wheat soft wheat and semolina (from durum wheat) flour doughs (from t = 0 to t = 108h). All dough samples aged at 25 °C showed a transition from strain stiffening to strain softening behavior. The critical strain was highest for semolina dough which showed the most solid-like viscoelastic behavior due to the higher protein content with the best protein quality. FTIR spectra indicated that β-sheet, β-turn and α-helix structures of each dough sample were affected differently due to aging process at 4 °C and 25 °C. Aging increased β-sheet content of the protein fraction in semolina and soft wheat dough and decreased it in hard wheat dough. Aging at higher temperature caused a significant increase in α-helix structure of only hard wheat dough sample while a decrease in β-turn structures of hard and soft wheat dough samples. With the combined effect of aging time and temperature, high molecular weight to low molecular weight ratio (HMW/LMW) ratios decreased for all dough samples especially at room temperature compared to aging at 4 °C. • LAOS of hard, soft and SemD showed SemD to have the highest resilience during aging. • Resilience was measured using the strain dependence of G′ M and G″ M , G′ L and G″ L . • Aging at 25 °C caused a sharp transition from strain stiffening to strain softening. • HWD and SWD had reverse trends in secondary structures of proteins, Sem stayed constant. • SDS-PAGE results showed that glutenin break down was highest in Sem dough.