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Physical Transformations of Agri-Food Products during Their Convective Drying: Characterization of the Contraction and Isotropicity of Okra

¹ Laboratoire de Matériaux de l’Héliophysique et Environnement (La.M.H.E.), Unité de Formation et de Recherche en Sciences Exactes et Appliquées (UFR/SEA), Université Nazi BONI, Bobo Dioulasso, Burkina Faso
² Laboratoire de Matériaux de l’Héliophysique et Environnement (La.M.H.E.), Unité de Formation et de Recherche en Sciences Exactes et Appliquées (UFR/SEA), Université Nazi BONI, Bobo Dioulasso, Burkina Faso
³ Laboratoire de Matériaux de l’Héliophysique et Environnement (La.M.H.E.), Unité de Formation et de Recherche en Sciences Exactes et Appliquées (UFR/SEA), Université Nazi BONI, Bobo Dioulasso, Burkina Faso
⁴ Laboratoire de Matériaux de l’Héliophysique et Environnement (La.M.H.E.), Unité de Formation et de Recherche en Sciences Exactes et Appliquées (UFR/SEA), Université Nazi BONI, Bobo Dioulasso, Burkina Faso
⁵ Laboratoire de Matériaux de l’Héliophysique et Environnement (La.M.H.E.), Unité de Formation et de Recherche en Sciences Exactes et Appliquées (UFR/SEA), Université Nazi BONI, Bobo Dioulasso, Burkina Faso

Journal of Minerals and Materials Characterization and Engineering·Volume 11 (2023)·Pages 249–259·Published 16 October 2023·DOI10.4236/jmmce.2023.116018

Abstract

The physical transformations in terms of contraction of okra dimensions during convective drying were examined. During drying, the lateral and longitudinal dimensions of okra decrease over time. The lateral dimensions go from their initial value to around 53 % , 65 % and 66 % of this value after 530 min. The length of the two samples used goes from 8.65 and 9.02 cm to 6.79 and 7.52 cm after 14,300 min, i.e. a variation of 78.50 % and 83.37 % . All the two directions give variations almost linear depending on the water content. These linear contractions result in a volume contraction of the okra. It considerably decreases in volume during the drying process. The volume goes from 831.32 cm 3 to 367.57 cm 3 in min, a variation of 44.22 % . The isotropic index reveals that okra does not behave the same in the lateral and longitudinal directions. It contracts its diameter more than its length.

KeywordsPhysical TransformationsContractionIsotropicityOkra

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Physical Transformations of Agri-Food Products during Their Convective Drying: Characterization of the Contraction and Isotropicity of Okra

Abstract

References (30)