A CFD model as a tool to simulate β-lactoglobulin heat-induced denaturation and aggregation in a plate heat exchanger

• A CFD model was developed to predict β-lactoglobulin denaturation in a plate heat exchanger.
• A k–ε turbulence model is well-suited for modeling plate heat exchanger hydrodynamics.
• The protein denaturation was measured before and after heat treatment at pilot-scale.
• The kinetic parameters provide a close correlation between the CFD model and experiments.
• The unfolded β-lactoglobulin species is the precursor of fouling in the exchanger.

During the pasteurization process, the thermal treatment of milk and its derivatives in plate heat exchangers is limited by protein fouling. The deposition mechanism onto the heat transfer surface involves the denaturation and aggregation of β-lactoglobulin. In this work, a 2-D CFD analysis was conducted to simulate locally the heat-induced protein denaturation mechanisms. Firstly, we present various intermediate validations of the ability of the numerical model to capture the hydrodynamics, by showing the similarity of CFD results and experimental data. Finally, the close agreement between the denaturation level obtained by CFD and that obtained experimentally indicates the ability of the numerical model adopted to simulate the chemical reaction. The analysis of the species present in the plate heat exchanger is related to the deposit mass distribution along the heat exchanger using CFD data. It has been shown that the unfolded species are deposit precursors and that the distribution of the deposit is correlated to this source.