From hot melts to cool dies: MRI mapping of anisotropic structure formation during high-moisture extrusion of plant proteins

To aid the transition from our current meat-focused diet to a healthier and more sustainable plant-based diet, replacement products that resemble meat a thought to be essential. Industry has invested a lot in the production of textured plant-protein products that resemble the fibrous texture of meat at multiple length scales. These products are made through a process called high-moisture extrusion, yet the exact structuring mechanisms occurring during this process are not yet fully understood. In this work, Magnetic Resonance Imaging is used to characterise these protein extrudates, initially after production and at multiple length scales, but eventually also in real time during production in a lab. The former method will enable a better understanding on how structure can best resemble meat whereas the latter process will enable the direct calibration of computer models that can simulate the flow of a protein melt during extrusion which will speed up and reduce the cost of product innovation.