The effect of different porous media on moisture loss and oil absorption profiles during frying using glass micromodels

Pablo CortesDept. of Chemical and Bioprocess Engineering, Pontificia Universidad Catolica de Chile, Santiago 6904411, ChileGuillermo Badillo and Luis SeguraDept. of Food Engineering, Universidad del Bio-Bio, Avda. Andres Bello S/N, Chillan, ChilePedro BouchonDept. of Chemical and Bioprocess Engineering, Pontificia Universidad Catolica de Chile, Santiago 6904411, ChileASIS-UC Interdisciplinary Research Program on Tasty and Healthy Foods, Pontificia Universidad Catolica deChile, Santiago 6904411, ChileDOI 10.1002/aic.15088Published online in Wiley Online Library (wileyonlinelibrary.com)Microstructure plays a key role in oil absorption during frying. The aim of this work was to improve our understandingof the relationship between microstructure and oil absorption, through the use of glass micromodels to obtain evidenceof transport phenomena in three porous networks. Micromodels were saturated with water and partially immersed in oilat 1908C. Moisture and oil profiles were imaged to get water and oil saturation maps. Image and fractal analyses wereperformed to describe the morphology of the evaporation and oil fronts. Results showed that higher porosity facilitatedthe moisture removal and promoted greater oil absorption during cooling. The fractal dimension showed that micro-structures with a relatively high number of fine capillaries were less stable and propitiated fingering during the advanceof the evaporation front. In all matrices, the disruption of the surface oil film due to air penetration was a critical factorto stop oil imbibition.