Processing of concentrated and dry particulate food materials is a common operation in food industry. Think about spray drying to convert a concentrated dairy formulation into a powdered infant formula, about the use of milling and air classification to manufacture a dry-enriched pea protein concentrate, or extrusion of a paste through a nozzle during 3D food printing. While such operations are common, these often are carried out and designed based on empirical knowledge and optimized via trial and error.
In our group we therefore employ and develop experimental & modelling approaches to study and unravel underlying dynamic phenomena that play a role during processing of concentrated and dry materials. In several projects we collaborate with food industry, for whom we ultimately aim to develop mechanism-based guidelines for process optimization and new sustainable processing concepts that can be breakthroughs in terms of product quality and/or energy efficiency. Within our group we have three research lines.
Dewatering and drying process
Dewatering and drying processes are responsible for approximately 10-15% of the total industrial energy use (80 PJ/year). In our research we adopt and develop small-scale approaches such as sessile single droplet and thin film drying to study drying processes such as spray, drum and agitated thin film drying. Experimental results are used for model development of phenomena responsible for the dynamics of product formation during drying (e.g. particle structure formation, release or degradation of specific compounds). Recently, our lab acquired a pilot-scale spray dryer / agglomerator (25 kg/h water evaporation). This spray dryer is used both for research and education purposes.
Dry fractionation for making new plant-based (protein) ingredients
Dry fractionation via combination of milling and dry separation is a highly interesting technique to produce protein or fibre-enriched cereal and legume ingredients. It not only is inherently more energy efficient compared to wet fractionation processes, but it also delivers highly functional ingredients with preserved native properties. Current research is investigating amongst others new driving forces for dry separation (i.e. electrostatic separation) and combining dry fractionation with fermentation to prepare protein-enriched ingredients with enhanced nutritional value.
3D Food Printing
We investigate 3D Food Printing being a rapidly emerging technology with major promise towards making personalized foods. Although the technique suggests a simple translation from a digital food design to an attractive food product, in practice, there are many challenges ahead. Therefore, we investigate the relationship between rheology and processing of pastes by extrusion-based 3D printing. It should lead to more accurate control for 3D printing of high-quality foods. We also investigate new 3D printed food concepts that have designed component distribution such that the sensory perception can be altered. The latter approach allows making healthier foods that contain less sugar, fat or salt.