Effect of non-covalently bound alkaline amino acids on the structural characterization, microstructure, and rheological properties of whey protein emulsion gel
Qingfeng Ban, Yujie Lin, Jiaxuan Li, Jianjun Cheng, Yunqing Jiang, An Jingjing
Abstract
The objective of this study was to explore the impact of L -arginine (Arg) and L -lysine (Lys) on the structural changes and rheological properties of whey protein isolate (WPI) emulsion gels through the utilization of multi-spectroscopic techniques and rheological analysis. The results indicated that the incorporation of Lys/Arg caused WPI molecules to become unfolded, thus exposing hydrophobic amino acids and altering the microenvironment of aromatic amino acids. Microstructural studies revealed that WPI emulsion gels containing 0.5% Lys or 2% Arg resulted in a more uniform and compact network structure. This phenomenon could be attributed to the capability of Lys/Arg to improve the hydrophobic interactions and hydrogen bonding between molecules during gel formation, ultimately leading to a network structure characterized by excellent rheological properties, textural properties, and water-holding capacity. These findings provide a theoretical for the development of emulsion gels with improved structural and rheological properties. • Lys/Arg induced the exposure of aromatic and hydrophobic amino acid. • Emulsion gels were fabricated with different Lys/Arg concentrations. • Lys/Arg improved the rheological and structural properties of WPI emulsion gel. • Lys/Arg promoted the formation of tight gel network structure.