Effect of ultrasound treatment on interactions of whey protein isolate with rutin

Rutin is a biologically active polyphenol, but its poor water solubility and low bioavailability limit its application to the food industry. We investigated the effect of ultrasound treatment on the properties of rutin (R) and whey protein isolate (WPI) using spectral and physicochemical analysis. The results revealed that there was covalent interaction between whey protein isolate with rutin, and the binding degree of whey isolate protein with rutin increased with ultrasound treatment. Additionally, solubility and surface hydrophobicity of WPI-R complex improved with ultrasonic treatment, and a maximum solubility of 81.9 % at 300 W ultrasonic power. The ultrasound treatment caused the complex to develop a more ordered secondary structure, resulting in a threedimensional network structure with small and uniform pore sizes. This research could provide a theoretical reference for studying protein-polyphenol interactions and their applications in food delivery systems.

Automated summary

Ultrasound treatment was found to enhance the binding degree between whey protein isolate and rutin, and improve the solubility and surface hydrophobicity of the WPI-rutin complex. The treated complex also developed a more ordered secondary structure with small and uniform pore sizes. This research provides a theoretical reference for studying protein-polyphenol interactions and their applications in food delivery systems.