Food drying and frying have something in common, which is the formation of a moving interface where most of the heat is absorbed as a latent heat of evaporation or sublimation. Based on that, it was possible to model deep fat frying, air drying, freeze drying, steam drying and spray drying using a single model based on moving interface. This is possible even though drying time could vary in these processes from few seconds to hours. The model presented in this paper is an extension to our published unified model, which was partially successful in describing these processes. The major modification is the inclusion of a moisture diffusion region surrounded by a wet core and dry crust regions. This modification has significantly improved the theoretical prediction of the experimental measurements available in the literature. (C) 2008 Elsevier B.V. All rights reserved.