title: Effect of ultrasound-assisted osmotic dehydration pretreatment on the convective drying of strawberry.
abstract: The work was planned to produce dietetic dehydrated strawberries with application of ultrasound osmotic dehydration (UOD) as pretreatment. A Box-Behnken design (BBD) were employed to characterize the UOD strawberry process, optimize and investigate the effect of independent variables like ultrasound time (10, 20 and 30min), concentration of osmotic solution (distilled water, 32.5 and 65 °Brix) and temperature (20, 30 and 40°C) on the water loss (WL), solid gain (SG) and weight reduction (WR). The same BBD were used to estimate the main effects of OD without ultrasound treatment. A multi-criteria optimization based on maximal possible values of WL and WR and minimal value of SG was achieved. This was 20.5min of ultrasound time, 47.5 °Brix osmotic solution concentration and 31°C medium temperature. The effects of UOD carried out under the optimized operating conditions on kinetics of convective air drying of strawberry at 40, 50 and 60°C, and velocity of 1m/s, using the phenomenological model of Coupled Washing/Diffusion (CWD). Starting accessibility, moisture effective diffusivity Deffvalue and activation energy (Ea) were calculated from similar-Fick's law and analogous Arrhenius equation, respectively with and without shrinkage correction. Color difference, Chroma and hue angle of fresh and UOD-air dried strawberries were evaluated. Quality attributes were estimated through the assessment of the phenolic content, antioxidant activity, rehydration capacity, and X-ray powder diffraction characteristics.
authors.affiliation: Université de Tunis El Manar, Unité de recherche «Chimie des matériaux et de l'Environnement», Institut Supérieur des Sciences Biologiques Appliquées de Tunis (ISSBAT), 9, rue Zouhair Essafi, Tunis 1006, Tunisia. Electronic address: ezzeddineamami@yahoo.fr.
authors.forename: Ezzeddine
authors.initials: E
authors.lastname: Amami
authors.affiliation: Université de Tunis El Manar, Unité de recherche «Chimie des matériaux et de l'Environnement», Institut Supérieur des Sciences Biologiques Appliquées de Tunis (ISSBAT), 9, rue Zouhair Essafi, Tunis 1006, Tunisia.
authors.forename: Wissal
authors.initials: W
authors.lastname: Khezami
authors.affiliation: Université de Tunis El Manar, Unité de recherche «Chimie des matériaux et de l'Environnement», Institut Supérieur des Sciences Biologiques Appliquées de Tunis (ISSBAT), 9, rue Zouhair Essafi, Tunis 1006, Tunisia.
authors.forename: Salma
authors.initials: S
authors.lastname: Mezrigui
authors.affiliation: Department of Food Engineering and Technology, School of Engineering, Tezpur University, Napaam, Assam, India.
authors.forename: Laxmikant S
authors.initials: LS
authors.lastname: Badwaik
authors.affiliation: Université de Sfax, Groupe de recherche en Génie des Procédés Agroalimentaires, Laboratoire de recherche en Mécanique des Fluides Appliquée - Génie des Procédés-Environnement, Ecole Nationale d'Ingénieurs de Sfax (ENIS), Tunisia.
authors.forename: Asma Kammoun
authors.initials: AK
authors.lastname: Bejar
authors.affiliation: University of La Rochelle-Faculty of Science and Technology, Laboratory of Engineering Science for Environment (LaSIE UMR 7356 CNRS), Avenue Michel Crépeau, 17042 La Rochelle, France.
authors.forename: Carmen Tellez
authors.initials: CT
authors.lastname: Perez
authors.affiliation: Université de Sfax, Groupe de recherche en Génie des Procédés Agroalimentaires, Laboratoire de recherche en Mécanique des Fluides Appliquée - Génie des Procédés-Environnement, Ecole Nationale d'Ingénieurs de Sfax (ENIS), Tunisia.
authors.forename: Nabil
authors.initials: N
authors.lastname: Kechaou
mesh_terms: D000388:Air; D000975:Antioxidants / Q000737:chemistry; D003116:Color; D003890:Desiccation / Q000379:methods*; D031985:Fragaria / Q000737:chemistry*; D009995:Osmosis; D010636:Phenols / Q000032:analysis; D013696:Temperature; D013997:Time Factors
chemical_list: D000975:Antioxidants; D010636:Phenols
keywords: Color and phytochemical analysis; Convective air drying; Dietetic dehydrated strawberry; Moisture diffusivity with shrinkage; Ultrasound assisted osmotic dehydration; X-ray diffraction