Abstract. A mathematical model based on Hertz's theory of contact stress was developed for the analysis of cocoa pod deformation when subjected to a uni-axial compressive stress, in its lateral axis, between rigid parallel plates. A two-sample t-test comparison of the experimentally measured values of the stiffness modulus and those obtained from the initial Hertz theory equations indicated a very significant difference, which was observed to be due to the irregular shape of the pod, its furrowed circumference and internal hollow-ness, contrary to some basic assumptions of the theory. Correcting factors developed to account for these irregularities significantly improved the predictions of the modified Hertz relation. The shape factor, which ex-pressed the deviation of the material from a true ellipsoid in terms of the material contact area with the loading plate, was found to be the most critical correction factor in terms of which a combined correction factor could be expressed to simplify necessary computations.