Abstract: In this paper, the content and particle size distribution of glutenin macropolymer (GMP), protein secondary structure, and starch gelatinization properties in doughs made with hot water at different temperatures (55, 65, 75, 85 and 95 ℃) were investigated by the Kjeldahl method, particle size analysis, Fourier transform infrared spectroscopy and a rapid visco analyzer. The results showed that the content of GMP in hot-water dough increased significantly with the increase of water temperature (P < 0.05), and GMP was transformed from small to medium and large particle sizes; the α-helix and β-sheet structures were partially converted into β-turn and random coil structures. The degree of starch gelatinization in hot-water dough gradually increased with the increase in water temperature, while the peak viscosity, minimum viscosity, breakdown value, final viscosity, setback value and time to peak viscosity decreased, more steeply above 75 ℃.

Key words: hot-water dough; mesoscopic characteristics; glutenin macropolymer; starch gelatinization; viscosity properties