Isothermal drying of plant-based food material: An approach using 2D polydimethylsiloxane (PDMS) micromodels Marco Guzmán-Meza a , João Borges Laurindo b , Marcela Jarpa-Parra c , Luis Segura-Ponce a,⇑ a Food Engineering Department, Universidad del Bío-Bío, P.O. Box 447, Chillán, Chile b Department of Chemical and Food Engineering, Federal University of Santa Catarina, 88040-900 Florianópolis, SC, Brazil c Universidad Adventista de Chile, Box 7-D, Chillán, Chile highlights  Proposed new porous medium approach to represent plant-based food material.  Developed methodology to build micromodels representing plant- based food material.  Homogeneous depth of pores and throats obtained by the Toyobo- KM43GS plate.  Pyranine aqueous solution allowed easy observation of drying fronts. graphical abstract article info Article history: Received 29 July 2019 Received in revised form 4 November 2019 Accepted 22 November 2019 Available online xxxx Keywords: Porous media Micromodels PDMS Plant-based food material Drying mechanisms abstract The aims of this study were to build PDMS micromodels that simulated plant-based food material, and use them to investigate the drying mechanisms at pore-scale, the drying front morphologies and the dry- ing curves during the isothermal drying process. Micromodels were built using a modified photolitho- graphic technique. Three normal pore size distribution functions were developed to simulate the plasmodesma, intercellular space, and cell wall. Micromodels were impregnated with a pyranine aqueous solution and placed on a balance illuminated with ultraviolet light. Isothermal drying was developed by natural convection (20 °C). Drying front morphologies displayed a hierarchical behavior in which pores with the largest diameter dried first. Drainage and surface evaporation sequences and internal evapora- tion controlled the drying of PDMS micromodels. The micromodels were useful to simulate plant-based food material and study isothermal drying of such porous media. The results led to the proposal of some drying mechanisms that were involved. Ó 2019 Published by Elsevier Ltd. 1. Introduction Drying is a common method to remove liquid from a porous material by evaporation. In this process, the gas phase replaces https://doi.org/10.1016/j.ces.2019.115385 0009-2509/Ó 2019 Published by Elsevier Ltd. ⇑ Corresponding author. E-mail address: lsegura@ubiobio.cl (L. Segura-Ponce). Chemical Engineering Science xxx (xxxx) xxx Contents lists available at ScienceDirect Chemical Engineering Science journal homepage: www.elsevier.com/locate/ces Please cite this article as: M. Guzmán-Meza, J. B. Laurindo, M. Jarpa-Parra et al., Isothermal drying of plant-based food material: An approach using 2D polydimethylsiloxane (PDMS) micromodels, Chemical Engineering Science, https://doi.org/10.1016/j.ces.2019.115385