DRYING CHARACTERISTICS OF OKRA PODS DURING DRYING PROCESS IN A HOME MICROWAVE OVEN

Kassem, Abd El-Wahab S.; Aboukarima, Abdulwahed M.; Morghany, Hamza A.

doi:10.21608/mjae.2012.102610

DRYING CHARACTERISTICS OF OKRA PODS DURING DRYING PROCESS IN A HOME MICROWAVE OVEN

Document Type : Original Article

Authors

¹ Proffesor, Agricultural Engineering Department, Faculty of Agricultural, Alexandria University, Egypt.

² Researcher, Engineering Research Institute, Agricultural Research Center, Egypt.

³ Assistant Professor at Community College, Huraimla, Shaqra University, P.O. Box 300, Huraimla 11962, Saudi Arabia.

10.21608/mjae.2012.102610

Abstract

Okra is an important vegetable for different people all over the world. Because of its high moisture content, okra is susceptible to rapid deterioration. The aim of the present work was to determine the effect of a home microwave output powers on drying of okra pods. Okra was dried from initial moisture content of about 89.12% (w. b) to a safe level of about 9.62% (w. b) under different microwave output power levels (75, 150, 300, 500, 700 and 900 W) using the process 1 min ON and switch OFF the microwave oven for 5 min. The obtained data show that, there by increasing the used microwave output powers for drying sample of 100 g, the drying time leading to decrease from 19 to 13 min. To determine the kinetic drying model parameters, the drying data were fitted to four drying models based on the ratio of the final and initial moisture contents versus drying time. Among of the models proposed, the Midilli-Kucuk model gave a better fit for all drying conditions applied. It is expected that this study would be very beneficial to those dealing with the microwave drying systems of the future.

Main Subjects

Processing Engineering of Agricultural Products

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