Generation of porous starch beads via a 3D food printer: The effects of amylose content and drying technique

A new approach via extrusion-based 3D food printing (3DP) was developed to fabricate porous spherical beads from corn starches with different amylose contents (i.e., 25, 55, and 72 %). The effects of amylose content and drying method, i.e., freeze-drying and supercritical carbon dioxide (SC-CO2), on the structural properties of the starch beads were investigated. The shape and size of the 3D-printed beads highly depended on the starches' amylose content as it affected the rheological properties of the inks. The smallest 3D-printed bead size was ∼980 μm generated from high amylose (72 %) corn starch. 3DP of starch with high amylose content along with SC-CO2 drying resulted in starch beads with superior properties. The SC-CO2-dried beads showed a significantly higher surface area (175 m2/g) than the freeze-dried ones (<1 m2/g).