Research pick: Spud be good to me - "Mathematical and numerical modelling of coupled heat and moisture diffusions during infrared drying of a potato slice"

Research in the International Journal of Mathematical Modelling and Numerical Optimisation has looked at how direct heating with infrared could be used to dry food for preservation more efficiently, more predictably, and more sustainably, than do current approaches.

The researchers have modelled the movement of heat and the loss of moisture in food dried using infrared using a potato slice as a test sample. Their findings suggest that infrared drying offers precise control and can be scaled up.

Drying is one of the oldest and most important methods of food preservation, particularly in regions where refrigeration and storage infrastructure are limited. Standard hot-air drying is energy-intensive and inefficient, and can reduce food quality. Infrared drying differs in that the energy penetrates the food and this avoids the issues associated with surface heat transfer. It thus speeds up moisture loss and makes the process more uniform.

The team’s simulations of the infrared drying process were compared with previously published experimental data and found to agree closely with it. Having validated the model, the team could then test how different operating conditions might affect the drying process. The results show that moisture evaporation increases sharply at the start of the process before settling into a quasi-steady state, in which conditions change more slowly. Crucially, the evaporation rate rises in proportion to the square of the infrared temperature, underlining how sensitive drying performance is to radiation intensity.

The model might be used by food scientists and producers to investigate and control desiccation of food with the potential for reducing food waste, a growing problem around the world.

Tudu, B., Barman, N., Chattopadhyay, H., Simlandi, S. and Chatterjee, S. (2025) ‘Mathematical and numerical modelling of coupled heat and moisture diffusions during infrared drying of a potato slice’, Int. J. Mathematical Modelling and Numerical Optimisation, Vol. 15, No. 4, pp.400–416.