A Heat and Mass Transfer Model for Predicting the Drying of Beef During Biltong Processing Using Infrared-Assisted Hot Air Drying

Purpose The aim of this study was to develop a coupled heat and mass transfer model to predict the temperature and moisture content of beef during biltong processing using infrared-assisted hot air drying (IRHAD). Methods The developed model was implemented and solved using Ansys Fluent CFD software...
Ausführliche Beschreibung

Purpose The aim of this study was to develop a coupled heat and mass transfer model to predict the temperature and moisture content of beef during biltong processing using infrared-assisted hot air drying (IRHAD). Methods The developed model was implemented and solved using Ansys Fluent CFD software. Drying experiments conducted using an infrared-assisted hot air dryer were used to determine the moisture diffusivity, and the heat and mass transfer coefficients used in the model. The experiments were done at an infrared emitter power level of 750 W; drying air temperature of 30, 35, and 40 °C; and velocity of 1.5 and 2.5 m $ s^{−1} $. Results The simulation slightly overpredicted the temperature in the first hour of drying and underpredicted the temperature towards the end of the drying period. Consequently, the predicted moisture ratio (MR) was underpredicted at the onset of drying and agreed with the experimental values towards the end of the drying period. The simulation results were validated using a new set of experimental results, and the suitability of the model assessed using the $ R^{2} $ (0.9790 for temperature and 0.9579 for MR) and RMSE (1.99 for temperature and 0.0698 for MR). Conclusion The model can guide the application of IRHAD in the processing of biltong and forms a theoretical basis for analysing the application of IRHAD to other food and biobased products. Ausführliche Beschreibung