Development of 3D-printed chocolate fortified with collagen peptides

Although collagen peptide-enriched functional foods have been extensively developed, the incorporation of collagen peptides into chocolate matrices for 3D printing applications has not yet been explored. Therefore, this study aimed to develop 3D-printed functional chocolate enriched with collagen peptides. The collagen peptide microcapsules were prepared using porous starch/β-cyclodextrin as composite materials via spray drying. The effects of processing parameters (including core-to-wall ratio, solid content, and inlet temperature) on encapsulation efficiency were first evaluated, and the resulting microcapsules were characterized using FTIR, XRD, and SEM. Subsequently, the effects of microcapsule addition levels on the rheological properties, textural characteristics, and printing accuracy of chocolate were investigated. The results showed that the optimized microcapsules achieved an encapsulation efficiency of 79.53% under the conditions of a core-to-wall ratio of 1:2, a solid content of 13%, and an inlet air temperature of 180 °C. Chocolate containing 12% microcapsules exhibited the highest printing accuracy (96.5%) under the optimized printing conditions of a printing speed of 25 mm/s, nozzle diameter of 0.8 mm, and printing temperature of 38 °C. Mass spectrometric analysis confirmed an L-hydroxyproline retention rate of 92.69% after printing, as well as the presence of collagen peptides in the 3D-printed products. Overall, this study provides a promising approach for the development of 3D-printed chocolate products fortified with collagen peptides.