Analytical solution of simultaneous heat and mass transfer equations during food drying

•Food drying equations (FDE) were stated as non-steady heat and mass transfer equations coupled at interface.•Rigorous dimensionless analysis of FDE was developed.•Differences of FDE with respect to Luikov’s equations were detailed.•Analytical solution of FDE with variable initial conditions was deduced.•Behavior of solution at constant properties and linear equilibrium was studied and compared with experimental.

A rigorous dimensionless analysis of simultaneous heat and mass transfer equations for food drying was developed and simplified for constant properties. From the simplified result, an analytical solution in 1D rectangular coordinate system was obtained. As opposed to Luikov’s Equations (LE), the reported solution considers the effect of temperature on interface moisture content. The analytical solution was obtained by Laplace transform and complex inversion integral with space dependent function as initial conditions. The solution behavior compared with some experimental data was detailed, and the potential of the reported solution for the study of interface phenomena and variable mass transfer properties was discussed.