Parameters affecting the printability of 3D-printed processed cheese

In considering three-dimensional (3D) printing of food materials, fundamental understanding of the "printability" characteristics of different food materials is of vital importance to successfully meet user needs. In this study, a processed cheese formulation was 3D-printed with a modified 3D printer. Both intrinsic factors (i.e., pH and intact casein content) and measureable attributes (i.e., texture, printing accuracy, rheology and microstructure) were analysed. Using rheological methods, the optimal viscosity range (7.55-10.94 Pa.s) at which processed cheese will print successfully (i.e., simultaneously flow from the extrusion head uninhibited and build a layered structure) was identified. Processed cheese with a higher pH (5.8) was found to give a printed product that was significantly (P < 0.05) softer, gummier and more resilient in texture than the same recipe with a lower pH (5.4 and 5.6). Printed cheese containing exclusively fresh curd was significantly (P < 0.05) harder than that containing mild or mature Cheddar cheese. 3D printing at higher temperatures (60 degrees C) led to harder and more resilient cheese than printing at lower temperatures (40 degrees C). Overall, formulation and printing parameters for processed cheese significantly affect properties relating to "printability".