Effects of high‐intensity ultrasound treatment on physiochemical properties of caseins‐cyanidin‐3‐galactoside conjugates
Feng Xue, Chen Li, Shenyan Wang
Abstract
Summary The application of protein‐polyphenol complexes is increasing and broadening in recent years. Due to their unique properties, these complexes are attracting increased research interest. In this study, the cyanidin‐3‐galactoside was grafted to the caseins using free radicles induced by ultrasound. The formation of conjugation between caseins and cyanidin‐3‐galactoside was confirmed by the decrease in free amino groups and sulfhydryl content. Conjugation with cyanidin‐3‐galactoside resulted in aggregation of caseins, which also led to increase in particle size, relative fluorescence intensity and random coil. Conjugation also disrupted the hydrogen bonds and decreased the electrostatic repulsion and hydrophobic interactions between caseins. The caseins‐cyanidin‐3‐galactoside conjugate had better emulsifying, gelation properties and lower thermal stability than that of caseins.