Improving the rheological and tribological properties of emulsion-filled gel by ultrasound-assisted cross-linked myofibrillar protein emulsion: Insight into the simulation of oral processing

• Published in: Ultrasonics sonochemistry 2025-01, Vol.112, p.107205, Article 107205
• Main Authors: Tao, Ye, Cai, Jiaming, Wang, Peng, Zhou, Lei, Chai, Jiale, Wang, Zixu, Xu, Xinglian
• Format: Article
• Language: English
• Subjects: Emulsion-filled gel; Emulsions - chemistry; Gel structures; Gels - chemistry; Large amplitude oscillatory shear; Muscle Proteins - chemistry; Myofibrillar protein; Myofibrils - chemistry; Rheology; Tribology; Ultrasonic Waves; Water - chemistry
• ISSN: 1350-4177; 1873-2828; 1873-2828
• DOI: 10.1016/j.ultsonch.2024.107205

[Display omitted] •Emulsion as active filler improved the rheological and tribological properties of gel.•Droplet size of emulsion and interaction with protein matrix co-affected gel quality.•Small droplet of emulsion helped form small gel bolus to enhance oral lubrication.•Sonication after crosslinking fabricated emulsion-filled gels with optimal quality. This study aimed to investigate the effect of ultrasound-assisted cross-linking of myofibrillar protein (MP) emulsions on the enhancement of rheological and tribological properties of emulsion-filled gel. The micro-morphology, texture, water hold capacity (WHC), chemical forces, linear shear rheological behavior, large amplitude oscillatory shear (LAOS), oil-released content, and simulated oral friction of the water-filled gel (WP-G), the original MP fabricated emulsion-filled gel (NP-G), the crosslinked MP fabricated emulsion-filled gel (NPG-G), and the ultrasound treated crosslinked MP fabricated emulsion-filled gel (NPGU-G) were determined. Results indicated that emulsion as filler phase significantly improved the rheological and tribological properties of the gel, especially for the ultrasound-assisted MP emulsion-filled gel (NPGU-G) group, the smaller droplet size of emulsion contributed to the density and structural uniformity of the gel. Based on the excellent hydrophobic interaction between emulsion droplets and protein matrix, the NPGU-G group presented enhanced hardness, gumminess, chewiness, hydrophobic interaction, creep-recovery behavior, and the retarded transition of nonlinear response. Furthermore, the lower oil-released content and reduced friction coefficient in the NPGU-G group also indicated that the smaller emulsion droplets contributed to the gel quality and mouth lubrication. Consequently, this study demonstrated that ultrasound-assisted cross-linked MP emulsion with smaller droplets can be successfully filled into gel structures, form a denser network structure, and improve the quality of the emulsion-filled gel.