Lutein-loaded glycosylated zein nanoparticles-Preparation, characterization, and stability in functional drink

In order to improve its carrying and delivery performance, zein was glycosylated with chitosan oligosaccharide (COS) by Maillard reaction to prepare glycosylated zein conjugates (GLCZ), and lutein was encapsulated within GLCZ for fabricating GLCZ-LUT nanoparticles. The results revealed the encapsulation efficiency of lutein loaded in zein (Z-LUT) was greatly increased from 69.33% to 85.75% when zein was modified with COS at a mass ratio of 1:3. The GLCZ-LUT nanoparticles presented unique spherical nanostructures, larger particle sizes (260–380 nm), increased zeta potential (−22.4 – -27.5 mv), and superior polydispersity (PDI <0.2). Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometry (XRD) confirmed that lutein was combined and encapsulated better by the Maillard-modified zein, and hydrogen bonding, electrostatic interactions, and hydrophobic interactions were the driving forces for formation of combined nanoparticle structures. Moreover, GLCZ-LUT showcased enhanced solubility, in vitro release, and antioxidant capacity of lutein. The stability of lutein under thermal, storage, and UV-light conditions in functional drinks was also significantly improved by GLCZ. The glycosylated COS/zein system, developed through the Maillard reaction, emerges as a leading contender for efficient lutein delivery in functional beverages.