Evaluation of a cabinet dryer developed for cassava chips

Abstract

Drying is a very important unit operation in the processing of fresh cassava root tubers into chips because it forestalls unprecedented and, sometimes, incalculable amount of losses often incurred by cassava farmers and processors due to spoilage and massive reduction in quality, and by extension, income. This study aimed at evaluating the performance of a prototype sawdust-­‐ fueled and fan-­‐forced convection cabinet dryer developed for cassava chips. The specific objectives were to develop regression equations to relate drying (or elapsed) time and moisture content for sun drying and drying of fresh peeled cassava chips on each of the three trays of the cabinet dryer. The dryer was evaluated by testing with 4.5 kg of fresh peeled cassava tuber chips. Regression equations were developed to relate percentage moisture contents of the drying cassava chips and elapsed (or drying) time for the two types of drying media. While it took 16 hours to sundry 4.5 kg of the peeled cassava chips to a safe moisture content of 13.9 % w. b. during the humid raining season month of August, it took only 3 hours to bring the same mass of peeled fresh cassava chips to an average safe moisture content of 12.2 % w.b. when placed in the cabinet dryer during the same period of the year implying that there was a 15 hour (or 83.3 %) reduction in time required to dry the same quantity of the fresh peeled cassava chips to a safe moisture content when the cabinet dryer was used.