Effects of different mechanical processes on the structural and powdery properties of insoluble undenatured type II collagen.

This study aimed to investigate the effects of dynamic high-pressure homogenization (DHPH), dynamic high-pressure microfluidization (DHPM), and wet media milling (WMM) processes on the particle size, microstructure, triple helix structure, wettability and suspension stability of insoluble undenatured type II collagen (IUC-II). The structural and powdery properties were regulated by different processes and parameters. By contrast, WMM-treated IUC-II showed smallest particle size (15.70 μm), highest wetting rate (216.94 mm/h) and best suspension stability. However, individual mechanical processes caused partial disruption of IUC-II triple helix structure. Low-acyl gellan gum (LAGG) could bind to IUC-II through hydrogen bonds and hydrophobic interactions, which protected the triple helix structure and further enhanced powdery properties of IUC-II treated by WMM process, but restrained the soluble transition during digestion. These results demonstrated that WMM process was more suitable for enhancing powdery properties of IUC-II, while the triple helix structure of IUC-II could be effectively protected by LAGG.