How macroscopic structure of 3D printed protein bars filled with chocolate influences instrumental and sensory texture

Abstract The aim of this study was to determine the influence of the macroscopic structure of 3D printed protein bars with chocolate fillings on instrumental texture properties and sensory perception. Protein bars with different printing patterns (layered, rectilinear and concentric) were prepared by extrusion-based 3D printing. We found that protein bars with concentric chocolate infill pattern were significantly harder than bars with a chocolate layer, despite their similar chocolate content. Protein bars with a chocolate layer were significantly more cohesive than bars with a rectilinear pattern. Differences in instrumental texture were explained using spring models. Results of sensory ranking tests (n = 70 participants) were in good agreement with those of instrumental texture analysis. For protein bars with 16 g/100g chocolate content, protein bars with concentric pattern were perceived as the hardest. For protein bars with 25 g/100g chocolate content, protein bars with concentric and rectilinear patterns were both perceived significantly harder than bars with a chocolate layer. No significant differences were found between bars that differed in infill pattern for perceived chewiness and liking. We conclude that by changing the macroscopic structure (printing pattern) of 3D printed protein bars with chocolate fillings, the instrumental and sensory properties can be modified without affecting liking.