Complexation-driven 3D printable whey protein-lotus root composite gels for dysphagia foods

The development of customizable nutritional foods suitable for individuals with dysphagia remains a significant challenge. This study aimed to design a 3D-printed gel integration lotus root whole powder (WL) and whey protein (WP), tailored to meet the nutritional and textural needs of dysphagia people. Results showed that WP significantly improved the printability of lotus root gel (WLG). The 20 % WP formulation achieved optimal precision, with a base area of 407.77 ± 0.508 mm² and a height of 26.04 ± 0.031 mm, representing deviations of only 7.77 mm² and 1.04 mm from the designed model dimensions. Multi-scale characterization elucidated the printing mechanism, where WP improved the gel elasticity by reducing the starch molecular cross-linking and forming a microporous network that effectively enhanced moisture retention. Additionally, WP also induced α-helical to β-sheet transitions, strengthening the hydrogen bonding. Hydrophobic interactions promoted protein aggregation, while disulfide bonds facilitated covalent cross-linking, collectively forming a reinforced protein-starch matrix through multi-bond complexation. IDDSI testing confirmed the suitability of the lotus root whole powder/whey protein gel (WP-WLG) for dysphagia management. Furthermore, nutrient-fortified formulations demonstrated printing accuracy exceeding 93 %. The findings elucidate the gelation mechanism of WL-WP complex formation, offering a strategy for developing multi-nutrient, easy-to-swallow foods and a promising approach to personalized dysphagia nutrition.