Apple Convective Drying - Part II: Scrutinization of Monitoring Parameters Levels via Taguchi Optimization Approach

Wiem  Nasri; Ridha  Djebali; Marjan  Goodarzi; Mohamed Ammar  Abbassi; Said  Abboudi

Authors

Wiem Nasri Laboratory of Electro-Mechanic Systems (LASEM), National School of Engineers of Sfax, University of Sfax, Tunisia
Ridha Djebali Laboratory of Subatomic Physics, Nanosciences and Energetics, IPEST, University of Carthage, Tunisia
Marjan Goodarzi Sustainable Management of Natural Resources and Environment Research Group, Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Vietnam
Mohamed Ammar Abbassi UR: Materials, Energy and Renewable Energies, University of Gafsa, Tunisia
Said Abboudi ICB UMR 6303, CNRS, Université de Bourgogne Franche-Comté, UTBM Département COMM, F-90010, Belfort, France

Keywords:

convective drying, apple processing, Taguchi experimental design, optimization, factors levels

Abstract

Various parameters affecting the drying process of an apple were optimized by adopting the Taguchi experimental design technique (TEDT). Such a technique reduces the number of experiments while maintaining excellent accuracy and treating the measured values and their dispersion for the process parameters including the drying air temperature, the relative humidity, the velocity and the sample shape factor. The goal is to optimize the drying time as well as the internal mechanical stress as the average moisture content in the dried sample reaches value resultant in water activity of 90%. The optimized combination of conditions (parameters levels) were found to be in ranges: temperature [60, 70 °C], velocity [1.25, 2 m/s], relative humidity [5, 15%] and a sample shape ratio of 0.5 for an estimated average time 242.75 ???????????? and an estimated mechanical stress 5.46????7 ???????????? . A confirmation test by COMSOL using the optimized conditions gives excellent agreement with the estimated values emerging from the TEDT optimization and resulting in around four hours of drying time.