A model for a multicomponent system using the cell for determining apparent diffusion coefficients in gels and foods was developed. In this case, the generalized Fick’s law form was used as a constitutive equation for the diffusive molar flux of solutes. Using the method of eigenvectors and eigenvalues, the mass transfer equations were rearranged to simplify the mathematical treatment. Simple expressions for determining the diffusion coefficients of two or more solutes which diffuse in a rigid medium were obtained. In this case, experiments to study the diffusion of NaCl and KCl in cheese were shown and the corresponding effective diffusion coefficients were obtained.