Engineering plant-based protein-rich soft and bite-sized 3D printed dysphagia food

This study investigates the 3D printability of horse gram (Macrotyloma uniflorum) flour (HGF) substituted with chia (Salvia hispanica L.) seed flour (CSF) for engineering dysphagia food (Level 6) according to the International Dysphagia Diet Standardization Initiative (IDDSI). Four composite formulations of pretreated (germinated and roasted) HGF substituted by 5, 10, 15, and 20% (weight basis) CSF and one formulation without substitution of CSF were prepared, and their rheological characterization and printing performance were analyzed. The IDDSI tests for Level 6 dysphagia food were further conducted on the printed constructs and validated with their texture profile analysis results. The study revealed that germination followed by roasting of horse gram significantly (p < 0.05) increased the water holding capacity (WHC) of the formulations, which further impacted their rheological and textural properties. Substitution of 10% and 15% CSF demonstrated the best printing accuracy (>95%) in 2D and 3D printings. Further, the substitution of CSF in the formulations showed reduced hardness (6.77 ± 0.24 to 3.86 ± 0.10 N) and increased cohesiveness (0.153 ± 0.02 to 0.234 ± 0.01) in the 3D printed constructs, which are desirable for safe bolus formulation. The printed constructs were tested for the fork, spoon, and break-apart tests, and were observed to satisfy the criteria of Level 6 dysphagia food as per IDDSI guidelines.