Additive layer manufacturing of semi-hard model cheese: Effect of calcium levels on thermo-rheological properties and shear behavior

作者：Kern Christian^*; Weiss Jochen; Hinrichs Joerg

来源：Journal of Food Engineering, 2018, 235: 89-97.

DOI：10.1016/j.jfoodeng.2018.04.029

• Additive layer manufacturing
• Hot-melt extrusion
• 3D-printing
• Semi-hard cheese
• Small oscillatory strain rheology
• Capillary rheometry

Additive layer manufacturing (ALM) is an emerging technology for production of complex three-dimensional objects in the food sector. In this study, semi-hard model cheeses with different calcium levels (15.8 +/- 0.9 to 31 +/- 2 mg Ca g(-1) protein) were produced to investigate thermorheological properties and shear behavior at large strain to set up process parameters for hot-melt extrusion based ALM. The gel-sol transition temperature (51.7 +/- 0.2 to 60 +/- 2 degrees C) significantly (P < 0.001) decreased with declining calcium levels. Hence, extrusion die temperature was set to 60 degrees C in capillary rheometer experiments to mimic hot-melt extrusion based ALM. The extrudate strands were evaluated visually and recorded pressure profiles were analyzed to determine critical shear rates. It was demonstrated that critical shear rate (10-30 s(-1)) increased significantly (P < 0.001) with decreasing calcium levels and with increasing flowability (tan delta 60 degrees C). By exceeding the critical shear rate, extrusion instabilities occurred indicating limitation of ALM processes.

• 出版日期2018-10