Development of Golden Chlorella – Starch composite ink for 3D printed Dysphagia Diets

Abstract

Golden Chlorella (GC), a nutrient-rich microalga, shows high potential as a functional ingredient for 3D-printed foods designed for dysphagia diets. In this study, starch-based food inks containing GC were evaluated for their rheological behavior, printability, structural stability, and textural attributes using four starch types. Corn starch (CS) and potato starch (PS) inks exhibited superior printing quality, shape fidelity, and self-supporting capability, whereas waxy corn starch (WCS) ink displayed liquid-like behavior with low viscosity and Gʹ < Gʺ. Tapioca-based modified starch blend (TS; phosphate cross-linked tapioca starch with dextrin) produced inks with high hardness and cohesiveness, making them unsuitable for dysphagia applications. Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analyses indicated the presence of noncovalent bonds among starch, GC, and κ-carrageenan (κC) during gelatinization, accompanied by decreased crystallinity. In terms of rheological properties, increasing the starch concentration elevated the mechanical resistance during extrusion. Textural profiling confirmed that 10% CS, 20% CS, 20% PS, and 30% PS inks offered suitable softness, printability, and circularity for dysphagia diets. Overall, CS and PS demonstrated robust applicability as base materials for GC-containing 3D printing inks for dysphagia-friendly foods.