Oligosaccharide glycosylation of pigskin collagen: Impact on molecular structure, physicochemical properties, and gel functionality

This study aimed to investigate the effects of oligosaccharides (xylooligosaccharides (XOS), fructooligosaccharides (FOS), galactooligosaccharides (GOS), and isomaltooligosaccharides (IOS)) with different structures and molecular weights on the glycosylation modification of pigskin collagen (CO). Glycosylated CO was prepared via the Maillard reaction, and its molecular structure, physicochemical, and functional properties were analyzed using various analytical techniques. Results indicated increased glycosylation significantly altered the α-helix and random coil content, intrinsic fluorescence intensity, particle size, and ζ-potential of CO ( P  < 0.05). These modifications enhanced protein-protein and protein-water interactions, improving solubility, thermal stability, rheological properties, and creating a more uniform gel network structure. XOS, composed of the smaller molecular weight five-carbon aldose unit (xylose), exhibited the most significant effects, including enhanced thermal stability, water retention, and gel strength. However, the Maillard reaction-induced glycation browning caused a slight negative impact on the color of CO gels. In conclusion, oligosaccharide glycosylation significantly enhances the functional properties of pigskin CO, providing a promising strategy for its high-value utilization.