Generating 3D food printing materials through extrusion cooking: Printability and rheological properties of omega-3-enriched and chickpea flours formulations

Although deeply studied, the list of 3D Food Printing (3DFP) compatible materials is still short compared to traditional food manufacturing methods. This study focused on the printability of chickpea flour enriched with omega-3-rich oil and the effect of extrusion processing on printability. The functional and nutritional advantages of extrusion processing generated novel materials for 3D food printing. Four flours were used: NE (non-extruded), NEO (oil enriched), E (extruded), and EO (oil enriched). The water content varied across 14 formulations (34–36–40 % for NE and NEO and 66–68–70–72 % for E and EO), all printed at two temperatures (T1–25 ºC and T2–35 ºC). The prints’ dimensional accuracy was assessed to find the best formulation for each flour type. Following the least percentage error in each material´s top-view printability, the four best formulations were rheologically characterized (amplitude sweep, shear-viscosity, time-viscosity, temperature-viscosity, and recovery). Based on printability, the best formulations were NE-36-T1 (non-extruded sample with 36 % water content printed at 25 ºC) and E-72-T1 (extruded sample with 72 % water content printed at 25 ºC), yielding the lowest printing deviations (29.03 and 30.07). Omega-3 enrichment significantly decreased the yield stress (3262 Pa for NE-36 to 2831 Pa for NEO-36, and 3304 Pa for E-72 to 1766 Pa for EO-72). All formulations remained viscoelastic, with EO-72 having the lowest recovery percentage. These results showed the compatibility of extruded and non-extruded chickpea flour with 3DFP, granting their further integration as ingredients in more complex formulations.