13th World Congress of Food Sciences & Technology location:Nantes, France date:17-21 September, 2006
Gas filled intercellular spaces are considered the predominant pathways for gas transport through plant organs and, as such, are greatly related to the characteristics of gas exchange. To understand the transport mechanisms of gas diffusion of fruit tissue, a microscale model for the transport of O2 in the intercellular spaces, the cell wall network and the intracellular liquid phase was introduced. The objective of this study was (1) to verify the applicability of the microscale model of the gas transport at tissue level and (2) to quantify the pathways of gas transport in relation to the microstructure of fruit tissue. The 2D microstructure of pear tissue was modelled from light microscopy images using the ellipse tessellation method. Gas transport properties of the gas and liquid phases and the cell membrane were determined from available literature data. The O2 transfer in each of intercellular space, cell wall and cytoplasm was applied using diffusion laws and irreversible thermodynamics. The model was solved
using the finite element method. The results showed that the microscale model can be applied to study the gas transport in fruit tissue. The model quantified the pathways of gas transport in fruit tissue. The O2 transport was mainly by means of the intercellular space, the cell wall network and less through the intracellular liquid. The results have important consequences for respiration–related disorders of fruits.