A multivariate study on the effect of 3D printing parameters on the printability of gluten-free composite dough

BACKGROUNDThe advancement of three-dimensional (3D) food printing technology is significantly influencing the food processing industry. The present study utilized extrusion 3D printing to create a gluten-free dough composed of little millet flour (LMF), amaranth seed flour (ASF) and curry leaf flour (CLF). The primary objective was to elucidate the effects of various extrusion-based 3D printing conditions, including extruder nozzle diameter (ND), extrusion rate (ER), print speed (PS) and layer height (LH) on the printability parameters of the dough. RESULTSIn this study, three formulations of composite dough were prepared (i.e., S1, S2 and S3) by varying LMF, ASF and CLF compositions; among which S1 composite (LMF:ASF:CLF::30:60:10 w/w) was found to have comparable viscoelastic properties with the wheat dough. Central composite design (CCD) was selected with 30 experimental runs and 3D dough samples were printed using S1 composite by varying ND, ER, PS and LH. Principal component analysis of the printed samples accounted for 82.75% of variability and classified the samples into three confidence ellipses. From the results of the CCD model, four solution parameters in terms of ND:ER:PS:LH::mm: pulse mu L-1:mm s-1:%, namely, P1 (1.8:115:8:70), P2 (1.6:115:7.8:65), P3 (2:100:7.8:55) and P4 (2:105:6.2:75), with high desirability value (> 0.85) were selected for sample 3D printing and post-baking analysis. The P1 sample was found to have least print deformations, highest print fidelity (85.66%), and lowest hardness (55.95 N) and fracturability (39.66 N) values, and hence was selected as optimized product. CONCLUSIONThe present study provides parametric solutions for efficient 3D printing of gluten-free composite dough, aligning with the increasing dietary preferences and demand of novel functional customized foods. (c) 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.