title: A comparative study of dried apple using hot air, intermittent and continuous microwave: evaluation of kinetic parameters and physicochemical quality attributes.
abstract: In the study, the effectiveness of intermittent (IMWD) and continuous (CMWD) microwave drying and hot air drying (HAD) treatments on apple slices were compared in terms of drying kinetics (moisture diffusivity and activation energy) and critical physicochemical quality attributes (color change, rehydration ratio, bulk density, and total phenol content (TPC) of the final dried product. The temperature, microwave power, air velocity, and pulse ratio (PR) applied in the experiments were 40-80°C, 200-600 W, 0.5-2 m/s, and 2-6, respectively. Results showed that IMWD and CMWD more effective than HAD in kinetic parameters and physicochemical quality attributes. Also, results indicated CMWD had the lowest and highest drying time and effective diffusivity. The exponential model for estimating IMWD activation energy, considering absolute power (1/P) and pulse ratio were also represented. The color change in apple slices dried by HAD showed the highest change.
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Nahid
authors.initials: N
authors.lastname: Aghilinategh
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Shahin
authors.initials: S
authors.lastname: Rafiee
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Abolfazl
authors.initials: A
authors.lastname: Gholikhani
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Soleiman
authors.initials: S
authors.lastname: Hosseinpur
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Omid
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Seyed S
authors.initials: SS
authors.lastname: Mohtasebi
authors.affiliation: Department of Agricultural Machinery Engineering Faculty of Agricultural, Engineering and Technology University of Tehran Karaj Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Maleki
keywords: Dried apple; hot air drying; intermittent microwave; microwave drying; phenol compounds; physicochemical properties