3D printing porous ceramic materials

Promovendus/a: Elif Persembe

Promotor(en): Prof. dr. ir. Rob Ameloot, De heer Cesar Alejandro Parra Cabrera

In light of the rising protein demand, further expansion of animal-based food (over)consumption in Western countries is neither healthy nor sustainable. Emulsified plant-based meat analogues (PBMA) conveniently offer a sustainable alternative to emulsified meat products, of which a frankfurter-style cooked sausage is a typical example. Unfortunately, many emulsified PBMA do not meet consumers’ sensory expectations, in part due to our limited understanding of the impact of plant proteins and lipids on their physical stability and texture.

Therefore, this study evaluated the impact of commercial proteins and lipids on the physical stability and texture of a model system for such emulsified PBMA.

The study showed that the protein source has a significant impact, with potato protein standing out due to its strong gelation and firm gel structure. In contrast, the impact of lipids is often limited and protein-dependent, although coconut fat consistently leads to stronger gels because of its high solid fat content.

Since the protein source has a crucial impact, the effect of heating owas further investigated. This part focused on the impact of heating temperature on the aggregation and gelation of lab-extracted, native proteins from potato (Solanum tuberosum), mung bean (Vigna radiata), and pea (Pisum sativum) at a pH and salt concentration relevant for emulsified PBMA.

The study showed that all extracts aggregate and gel primarily through hydrophobic interactions, with enhanced interactions at elevated temperatures, also at temperatures at which the protein three-dimensional structure does not change, i.e., without protein denaturation.

It was also observed that the physical stability of gels from these extracts increases with higher temperatures, although the water binding of potato and pea gels is already remarkably high after heating at 50 °C, which is a fairly low temperature. Gels’ toughness also increases with higher temperature, across all extracts. However, the gels are only self-supporting upon heating above the temperature required to alter the protein structure, i.e., after protein denaturation.

3D printing is changing how we design and manufacture materials. This thesis explores how 3D printing can be used to create porous ceramics, carefully designed void spaces within the structure. Such structures are important for medical implants, filters, catalysts for chemical reactions, and even energy devices. In this work, new printing methods were developed and tested:

• A custom-built 3D printer that allows precise control of droplet size and layer thickness.

• Methods to make ceramic foams with complex shapes using sacrificial templates.

• High-resolution ceramic printing to create pores of different sizes and patterns.

• A feasibility study showing that 3D-printed ceramics can be used inside chemical reactors, improving efficiency.

The results show that 3D printing makes it possible to design ceramic materials with pores at different scales, tailored for specific applications. This opens the door to faster prototyping, cost-efficient production, and customized components in healthcare, energy, and industry.