Author: Egbe, E.W* and Jonathan, B.J, Ebienfa, P.D.I and Abu, H.C

Abstract:

Garlic (Allium Sativum) is a medicinal food and is also used as food ingredient and natural preservative. Freshly harvested garlic begins to loss its nutritional characteristics after harvest. Drying increases its shelf life and retains its proximate composition, aids in better packaging, which will serve as a marketing tool and also as a process whereby the activities of most decay-causing microbes are either deactivated or reduced to safe levels. Modelling the drying behaviour of garlic was investigated on thin layers within the drying temperature range of 60°C through to 100°C using a laboratory convective drying method (oven) and the emanating experimental data are fitted to the three thin- layer drying models such as page, Henderson-pabis, and Lewis model to determine the model that would suitably describe the drying kinetics of the garlic. The various related thin layer drying model constants and coefficients were obtained using regression methods. The result shows that drying took place almost entirely within the falling rate period. The temperature -dependent effective diffusivity was shown to be in values that ranged from 1.49×10-6 to 6.30×10-7m2/sec in the temperature range applied in this work. And the related activation energy was found to be 12.83kJ/mol. The fitting results also showed the Page model as suitable for predicting the thin layer drying kinetics of garlic.