Preparation and characterization of 3D printed texture-modified food for the elderly using mung bean protein, rose powder, and flaxseed gum

This study is aimed to evaluate the applicability of using flaxseed gum (FG) as a texture-modified agent for preparing dysphagia-oriented foods containing mung bean protein (MBP) and rose powder (RP) via 3D printing. Rheological and texture profiles, 3D printability, swallowing easiness/difficulty and in vitro digestion of ink formulations with different FG concentration (0%-1.5%) were evaluated. Inks containing 0.3%-1.2% FG showed uniform texture, improved viscosity, elastic modulus (G '), and fracture/yield stress than the one containing only MBP + RP. Further increase of FG content to 1.5% enhanced the incompatibility between MBP and FG and caused their microphase separation, which compromised inks' printability and stability of the printed shapes. Ink containing 0.9% FG showed desirable printing performance and self-supporting ability, and could be classified as level 4-pureed/extremely thick dysphagia-specific food. FG addition of 0.9% did not impede the digestion of MBP and retained a higher percentage of total phenolics during simulated gastrointestinal digestion.