Ginger starch-whey protein isolate composite gels: Structural regulation and swallowing suitability for...

This study investigated the potential application of ginger starch (GS) in texture-modified foods for dysphagia management. GS gels were prepared at concentrations of 6%, 9%, and 12%, and composite gels were formulated by incorporating 4% whey protein isolate (WPI). Within the framework of the International Dysphagia Diet Standardization Initiative (IDDSI), both GS gels and GS-WPI composite gels at 6% starch concentration were classified as Level 6 solid foods, whereas the 9% and 12% systems corresponded to Level 7, demonstrating concentration-dependent swallowing adaptability. As GS concentration increased, gel strength, storage modulus, and crystallinity significantly increased. In contrast, the incorporation of WPI effectively reduced deformation resistance and the mechanical energy required during oral processing, thereby improving swallowing suitability. Multi-scale structural characterization, including LF-NMR, SEM, XRD, and FTIR analyses, demonstrated that GS formed a stable three-dimensional network capable of regulating molecular ordering and water mobility. The addition of WPI may have contributed to network reorganization through hydrogen-bond-related interactions and steric hindrance, facilitated the conversion of free water into immobilized water, and suppressed starch recrystallization. These structural modifications collectively enhanced water retention capacity and improved viscoelastic uniformity. Overall, the findings confirm that ginger starch represents a promising novel functional starch resource for dysphagia-oriented food design.