Determination of Gas Diffusivity and Skin Resistance for Three Cultivars of Japanese Pear Using their Actual 3D Geometry

Abstract

This research was conducted to study gas transfer in three cultivars of Japanese pear based on their actual geometry obtained from a 3D Laser Scanner. Gas diffusivity and skin resistance to gas diffusion found to be dependent on the cultivar. Gas diffusivity for ethane was found to be 8.10 1.2, 3.67 0.11 and 5.97 0.42 (10 8 m 2 s 1) for Kosui, Niitaka and Oushuu, respectively. Niitaka was found to have the highest skin resistance due to a noticeably lower number of lenticels on the skin. As expected gas diffusivity increased with increasing of temperature while skin resistance decreased. It was found that the diffusivity of CO2 is much lower than O2. The model was validated by conducting experiments to measure the internal concentration at different points of the fruit and comparing them with model results. The model was shown to be successful in predicting the internal gas concentrations.