The Effective Medium Theory (EMT), known in the field of physics to model conductive properties of heterogeneous chaotic media, has been applied to predict the thermal conductivity of sugar-based fruits and of potatoes as a function of the water content. With the thermal conductivity of the constituents, the composition and porosity as data, the equation derived from the EMT for continuous media was applied to apples, pears, and potatoes. The results when compared with experimental values obtained by the probe method and from the literature showed good agreement, with differences not larger than 8%, though the model appeared to be over predictive, particularly for higher water contents.