An experimental assessment of filament-extrusion models used in slicer software for 3D food-printing applications

Various filament-extrusion models have been assessed for their accuracy in predicting the width of filament deposited during extrusion-based 3D printing of food materials. Slicer software uses such models in algorithms to determine appropriate nozzle toolpaths and material extrusion flow rates for printing 3D structures. Prediction and experiment were compared for various printer operating conditions encompassing slow-to moderate-speed and coarse-to fine-resolution 3D food printing. The model that assumes filaments of oblong cross-section predicts filament width well. Fractionated animal fat and 20% rice-starch gel generally form smooth, continuous and stable filaments over a broad range of printer operating conditions, making them ideal materials for 3D food printing. Practical issues in 3D food printing were highlighted, including the non-uniformity of filament width that results from even the slightest build-platform slope or nozzle skew, and the relevance of the extrusion multiplier in slicer software for fine-tuning 3D printing to account for differences in rheology between food materials.