A theoretical model to predict the formation of pores in foods during drying

A theoretical model (ideal condition) to predict porosity in foods during drying is developed based on conservation of mass and volume principle, and assuming that volume of pores formed is equal to the volume of water removed during drying. As expected the ideal model may not be valid in many practical cases. The ideal model is then extended for non-ideal conditions, when there is either shrinkage, collapse or expansion, by defining a shrinkage expansion coefficient. Experimental porosity data from the literature was used to estimate the shrinkage-expansion coefficient for selected food materials.