Effects of dark tea soup on rheological, thermal and microstructure characteristics of dough

In order to study the influence of dark tea soup on processing characteristics of dough, texture, thermo-dynamic and rheological properties and microstructure were measured. The dough with tea soup gets better gel strength, hardness, springiness and chewiness values compared to dough control, especially as the concentration of tea soup was at 0.05 g/mL. The G′ and G″ enhanced gradually in the frequency region of 0.1–100 rad/s with the increase in concentration of tea soup in dough, indicating the stronger and stickier gluten network structure. By thermo-gravimetric analysis, the results showed that contrast to dough control (the weight loss was about 86%), the mass loss greatly reduced for the dough with tea soup (for example, the weight loss remained about 32% in dough with tea soup of 0.1 g/mL). The results of infrared, fluorescence and electron microscope clarified that the structure of gluten protein was reconstructed and re-polymerized to form tighter and stronger gluten network in dough with ingredients in tea soup. The addition of dark tea soup improved the processing characteristics (rheology properties and texture properties) of dough and would give nutrition and function to final products. This study proved the potential value of dark tea in flour products, and provided a certain basis for further exploring the interaction mechanism between the active components in dark tea and gluten protein and starch. Graphical abstract