Effect of corn Zea mays L. cob moisture content on the performance of a corn-cob sheller machine

Abstract

The object of the research is machine shelling efficiency. This study focused on the assessment of a fabricated corn Sheller machine and resolution of optimal moisture content percentage dry basis (% MCdb) for shelling corn-cobs. Corn-cobs samples at 8, 13 and 18 % MCdb were sorted into 3.15, 2.15 and 1.15 kg feed-masses, respectively. Samples were selected in triplicates for shelling operations time 5, 6 and 7 seconds. Standard method was used to determine the effect of shelling operation on corn-cobs’ quality variables. Response Surface Method was employed to optimize data with machine feed-mass and moisture content as independent variables, whilst responses being: shelled, un-shelled, damaged, un-damaged corn grains, as well as grain breakage ratio, machine shelling efficiency and shelling process time. The data gotten from the results were utilized to evaluate the corn-cob shelling machine and were analyzed using ANOVA at 95 % confidence interval. Corn-cobs 8 % MCdb shelled at 5 seconds and machine feed mass of 3.15 kg had the highest shelling efficiency of 97.78 %, followed by 13 % MCdb, feed mass of 2.15 kg, machine shelling efficiency 92.06 %; shelled in 6 seconds, lastly, 18 % MCdb, feed mass of 1.15 kg, shelling efficiency was 87.82 % shelled in 6 seconds. The resultant recorded response masses; shelled, un-shelled, damaged corn grain (kg) and grain breakage ratio recorded were at lower values. At lower machine shelling time, feed mass and moisture content percentage (% MCdb) of the corn cobs, higher shelled grains off the corn-cobs were recorded with reduced damaged grains, indicating higher shelling efficiency of the fabricated corn-cob Sheller machine.