Physicochemical properties and in vitro digestion of quinoa starch induced by combination of ultrasound and konjac glucomannan.

ABSTRACT

This study investigated the effects of konjac glucomannan (KGM) and ultrasound on the solubility, pasting properties, rheological behavior, thermal properties, structural characteristics, and digestibility of quinoa starch. The results demonstrated significant improvements in starch properties with both ultrasound and KGM treatment, with the most pronounced effects observed in the combined ultrasound and KGM treatment. This combined treatment led to enhanced energy storage modulus and loss modulus, indicating improved rheological properties. Additionally, combined treatment improved solubility, thermal stability, and digestibility and resulted in a more ordered structure and increased paste enthalpy compared with ultrasound or KGM treatment. Scanning electron microscopy and particle size analysis revealed a more compact starch structure following the synergistic treatment. X-ray diffraction and Fourier transform infrared spectroscopy showed a more organized, complex structure. These findings offer valuable insights into the application of ultrasound and KGM to enhance the performance and quality of quinoa starch.