Author(s)

Kondia Honoré Ouoba^1*, François Zougmore¹, Hélène Desmorieux²

¹Laboratoire des Matériaux et Environnement (LA.M.E.), Ecole Doctorale Sciences et Technologies (EDST), Université Ouaga I.
²Laboratoire d’Automatique et de Génie des Procédés, LAGEP, UMR CNRS 5007, Université Claude Bernard Lyon1-CPE-bat., Villeurbanne Cédex, France.

In this paper the influence of sample initial size on their convective drying at 80°C using convective dryer is determined. Results prove that initial size must be taken into account when drying process was estimated. This influence is limited by its form of cut. Comparing cubic form and parallelepiped (slice) one; results seem to show that thickness is the most important parameter governing the transfer phenomena during foodstuff convective drying. Three slices with thickness of 0.5 cm and surface area of 17, 82 and 112 cm² respectively, dry better than cubic sample with a = 1 cm or a = 2 cm of arrest and having respectively 6 and 24 cm² of surface area. All things seem to show that initial surface is not only the essential parameter; but also the thickness of the sample must be taken into account. Indeed, all of the samples with equal thickness (0.5 cm) and different exchange surfaces dry at the same time, about 210 min, comparing with cubic form 1 cm of arrest and 6 cm² of surface and drying time of 230 min. A new parameter noted D_c called characteristic diameter is so considered to bridge the gaps. It is defined to be the diameter of the biggest sphere we can cut into a sample. This parameter is independent of form of the sample, and time increase with characteristic diameter increasing.

Initial Size, Characteristic Dimension, Shrinkage, Cut Form, Exchange Surface Area

Ouoba, K. , Zougmore, F. and Desmorieux, H. (2018) Effect of Initial Size and Shape Importance on Masse Transfer during Convective Drying. Food and Nutrition Sciences, 9, 1514-1524. doi: 10.4236/fns.2018.912109.