DEVELOPMENT AND EVALUATION OF ROASTED GROUNDNUT BLANCHING MACHINE

Abstract

The roasted groundnut blanching machine was designed with the aim of achieving efficient blanching conditions and eliminating the drudgery associated with blanching of roasted groundnut. The roasted groundnut blanching machine was designed, fabricated and evaluated in the Department of Agricultural and Environmental Engineering, Federal University of Technology, Akure, Nigeria using roasted groundnuts purchased at local market. Different operating parameters such as blanch clearance, blanch speed and feed rate were considered for the purpose of this research. Factorial design comprising of three levels of feed rate, brush speed and blanch clearance with three replicates was used. The operating parameters of blanch clearance were varied from 10 mm to 20 mm at an increment of 5 mm for three different feed rates at 0.2 kg/hr, 0.4 kg/ hr and 0.6 kg/hr, respectively while the blanch speed was varied from 100 rpm to 200 rpm with and increment of 100 rpm. The results showed that the machine blanching capacity was found to be 50.91 kg/hr. Changes in machine operating parameters especially blanch clearance, feed rate and blanch speed affected the efficiencies of the machine such as blanching efficiency, cleaning efficiency, and mechanical damage. Data from this study led to the following conclusion. The maximum values of blanching efficiency of 89.46 % was obtained at blanches speed of 200 rpm, blanches clearance of 15 mm and feed rate 0.2 kg/hr. The maximum cleaning efficiency of 80.20 % was obtained at blanches speed of 200 rpm, blanches clearance of 15 mm and feed rate 0.2 kg/hr. The maximum mechanical damage of 10.16 % was obtained at blanches clearance of 10 mm, blanches speed of 200 rpm and feed rate 0.8 kg/hr while the minimum value of blanching efficiency of 44.57 % was obtained at blanches speed of 100 rpm, blanches clearance of 10 mm and feed rate of 0.8 kg /hr. The minimum cleaning efficiency of 38.72% was obtained at blanches speed of 100 rpm, blanches clearance of 10 mm and feed rate of 0.8 kg/hr. The minimum value of mechanical damage of 0.45 % was obtained at blanches speed of 200 rpm, blanches clearance of 20 mm and feed rate of 0.2 kg/hr, respectively. Hence, the evaluation parameters have effect on the performance of the machine. Results showed that the feed rate has considerable effect on the evaluation parameters while blanch speed has increase effect on evaluation parameters. From the results of this research, it was concluded that blanching of roasted groundnut with this machine could be better achieved and operated when the operating parameters especially blanch speed, blanch clearance and feed rate were regulated to 0.4 kg/hr, 15 mm and 200 rpm.