EVALUATION OF OPTIMAL STORAGE CONDITIONS FOR APPLE FRUIT USING A GAS EXCHANGE MODEL

A permeation-diffusion-reaction model was applied to study gas exchange of apple fruit. The gas exchange properties and respiration parameters of the fruit organ tissues were measured. The actual internal tissue geometry of the fruit was reconstructed from digital fruit images and the model was solved over this geometry using the finite element method. The model was validated based on measurements of internal gas concentrations and the gas flux of the fruit to its environment. Both measurements and an in silico study revealed that gradients of metabolic Rases exist in apple fruit, depending on diffusion properties and respiration of the different cultivars. The applicability of the model to predict the gas exchange of the fruit with its environment was demonstrated successfully and explained the differences in optimal storage conditions of different cultivars.