Impact of multi-frequency ultrasound processing with different treatment times on the structural quality of frozen wheat dough

This study investigates the effects of multi-frequency ultrasound treatment on the quality of frozen dough. We analyzed frozen wheat dough comprehensively for texture, viscosity, rheology, and structural quality characteristics under multi-frequency ultrasound (20 kHz, 20/40 kHz, and 20/40/60 kHz) with different treatment times (10, 20, and 30 mins). The dough treated with multi-frequency ultrasound increased elasticity and reduced hardness. Scanning electron microscopy revealed that 20/40/60 kHz for 30 min minimized freezing-induced morphological damage, decreased the tan delta in rheological analysis, and led to higher pasting and gelatinization enthalpy in starch granules, resulting in a more cohesive structure and lower free water content. Frozen dough hardness decreased by 52.1 %, which is associated with the control frozen dough with ultrasound frequency and duration changes. The spectral peaks in wheat flour frozen dough treated with single, dual, and trifrequency ultrasound had the same forms and positions as the control samples but were arranged in an orderly manner. This study demonstrates the potential of multi-frequency ultrasound to enhance the quality of wheat frozen dough by mitigating freezing-induced deteriorations, offering a promising approach to improving the processing of frozen dough.