Development of fat-reduced 3D printed chocolate by substituting cocoa butter with water-in-oil emulsions

This study developed a fat-reduced 3D printed chocolate by substituting cocoa butter with gum Arabic based water-in-oil emulsions. A 3D printed chocolate formulation was firstly obtained by adjusting the ratios of powder sugar, cocoa butter, and cocoa powder. The formulations with optimal 3D printability possessed cocoa butter, icing sugar, and cocoa powder ratio of 2:1:2.5. Different levels of cocoa butter (25%, 50%, and 75%) were substituted using water-in-cocoa butter emulsions with different water/oil ratios (2:8, 3:7, 4:6, v/v) to obtain fat-reduced 3D printed chocolate. Results from differential scanning calorimetry and X-ray diffraction study suggested these fat-reduced chocolate still maintained the desired polymorphic form V of cocoa butter. Apparent viscosity study suggested that these chocolate formulations possessed shear-thinning behavior and the viscosity increased with addition of water phase. Texture profile analysis indicated that incorporation of high emulsion content increased the snap quality of these chocolate. Emulsion droplet structure was observed in optical images of fat-reduced chocolate formulations containing water-in-cocoa butter emulsions. Partially replacing 75% cocoa butter by emulsions with water/oil ratio of 2:8 or 50% cocoa butter by emulsions with water/oil ratio of 3:7 didn't affect the original printability of 3D printed chocolate. Overall, this study successfully developed a 3D printed fat-reduced chocolate by using gum Arabic based water-in-oil emulsions substitute, which possessed the potential to become functional chocolate for incorporation of both hydrophilic and lipophilic bioactives in the future.