title: A permeation-diffusion-reaction model of gas transport in cellular tissue of plant materials.
abstract: Gas transport in fruit tissue is governed by both diffusion and permeation. The latter phenomenon is caused by overall pressure gradients which may develop due to the large difference in O(2) and CO(2) diffusivity during controlled atmosphere storage of the fruit. A measurement set-up for tissue permeation based on unsteady-state gas exchange was developed. The gas permeability of pear tissue was determined based on an analytical gas transport model. The overall gas transport in pear tissue samples was validated using a finite element model describing simultaneous O(2), CO(2), and N(2) gas transport, taking into account O(2) consumption and CO(2) production due to respiration. The results showed that the model described the experimentally determined permeability of N(2) very well. The average experimentally determined values for permeation of skin, cortex samples, and the vascular bundle samples were (2.17+/-1.71)x10(-19) m(2), (2.35+/-1.96)x10(-19) m(2), and (4.51+/-3.12)x10(-17) m(2), respectively. The permeation-diffusion-reaction model can be applied to study gas transport in intact pears in relation to product quality.
authors.affiliation: BIOSYST-MeBioS, Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Willem de Croylaan 42, B-3001 Leuven, Belgium.
authors.forename: Q Tri
authors.initials: QT
authors.lastname: Ho
authors.forename: Bert E
authors.initials: BE
authors.lastname: Verlinden
authors.forename: Pieter
authors.initials: P
authors.lastname: Verboven
authors.forename: Stefan
authors.initials: S
authors.lastname: Vandewalle
authors.forename: Bart M
authors.initials: BM
authors.lastname: Nicolaï
mesh_terms: D001692:Biological Transport; D002245:Carbon Dioxide / Q000378:metabolism*; D004058:Diffusion; D005638:Fruit / Q000378:metabolism*; D008954:Models, Biological; D009584:Nitrogen / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010539:Permeability; D031989:Pyrus / Q000166:cytology / Q000378:metabolism*
chemical_list: D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen