Mechanism of gum Arabic and mannoprotein complexes in suppressing bitter aftertaste and application in nutritious dysphagia gel beads

This study investigated the bitter aftertaste-masking mechanism of grape seed extract (MOPC) and developed a dysphagia-friendly delivery system using gum Arabic (GA)-mannoproteins (2082) complexes. Multi-scale characterization revealed the mechanism by which GA-2082 suppresses the bitter aftertaste of MOPC. The results demonstrated that at an optimal concentration (0.6 mg/mL GA), the formation of stable ternary complexes with artificial saliva (AS) was driven by free hydroxyl groups, OH⋯π interactions, and hydrophobic forces. This promoted chromogenic amino acid folding and α-helix exposure within AS, ultimately leading to the formation of a dense AS-GA-2082 molecular network. This network effectively hindered the penetration of MOPC through the salivary pellicle. Texture analysis further indicated that GA-2082 exhibited strong tongue-adhesion properties, significantly reducing the retention of MOPC on the tongue surface and subsequent activation of bitter taste receptors. When incorporated into sodium alginate (SA) gel beads, GA-2082 improved the encapsulation efficiency of MOPC, achieving a maximum of 97.68 % at 0.75 % SA concentration, while maintaining safe swallowing characteristics. These findings demonstrated GA-2082 possessed dual functionality as both an effective bitter aftertaste-masking agent and a delivery vehicle for bioactive compounds, providing a promising nutrient-dense formulations for dysphagia management.