In the burgeoning world of 3D food printing, the ink is the star of the show. But unlike traditional inks, these paste-like substances behave in complex ways under stress, making them challenging to characterize and optimize. Enter Bugday Yagmur, a researcher at Eindhoven University of Technology in the Netherlands, who has been delving into the rheological properties of these inks to better understand and predict their behavior during the 3D printing process.
Yagmur’s work, recently published in the journal Applied Rheology, which translates to Applied Rheology in English, focuses on the large deformation response of paste-like 3D food printing inks. This is a critical area of study, as the success of 3D food printing relies heavily on the ink’s rheological behavior. “Understanding how these inks flow and deform under processing conditions is crucial for improving the printing process and the quality of the final product,” Yagmur explains.
The challenge lies in the fact that these inks are prone to edge fracture at high deformations, making traditional steady shearing measurements impractical. To overcome this, Yagmur and her team used oscillatory measurements to characterize the rheology of these inks. They then developed a novel constitutive model—a mathematical representation of the ink’s behavior—to describe the deformation response and translate the information from oscillatory testing to steady shearing.
The model, a generalization of the Oldroyd-B model, incorporates a shear-rate-dependent viscosity following the Herschel-Bulkley model. This allows it to accurately predict the sample response at large deformations and the steady-shear flow response, which are both crucial for 3D food printing. “Our model provides a more accurate description of the ink’s behavior under processing conditions, which can help optimize the printing process and improve the quality of the printed food,” Yagmur says.
The implications of this research extend beyond the food industry. The methodology developed by Yagmur and her team can be applied to other materials that are challenging to characterize, such as those used in the energy sector. For instance, understanding the rheological properties of drilling fluids, cement slurries, and other paste-like materials could lead to improved drilling efficiency, better wellbore stability, and enhanced oil recovery.
Moreover, this research could pave the way for the development of new materials with tailored rheological properties, opening up new possibilities for 3D printing and other industries. As Yagmur puts it, “By understanding and controlling the rheological behavior of these materials, we can push the boundaries of what’s possible in 3D printing and beyond.”
In the rapidly evolving field of 3D printing, understanding and controlling the behavior of printing materials is key. Yagmur’s work is a significant step forward in this direction, offering valuable insights into the rheological properties of paste-like 3D food printing inks and providing a methodology that can be applied to other challenging materials. As the technology continues to advance, so too will our understanding of these complex materials, driving innovation and progress in the field.