Effects of cushion box and closed let-down ladder usage on mechanical damage during corn kernel handling: Cracking

Abstract

Corn kernels have a high susceptibility to mechanical damage due to their large size and mass. The main purpose of this study was to evaluate the effects of the cushion box and closed let-down ladder usage in minimizing mechanical damage to corn kernels during handling. Kernels from a single lot of cultivar KSC 705 were dropped in three methods (free fall, with a cushion box and with a closed let-down ladder) at five moisture contents (10, 15, 20, 25, and 30%), and three drop heights (5, 10 and 15 m) were evaluated for the percentage of various types of cracking and cracks index (CI). The results showed that the drop method had a significant effect on the damaged kernels. Sample kernels that fell without a ladder (free-fall) had a significantly higher average CI of 144.8. In the use of the cushion box, the average cracks index was calculated to be 103.3, which was decreased by about 29% more than the free fall. Sample kernels dropped with the closed let-down ladder had a lower average CI of 51.6, which showed that the closed let-down ladder significantly helped to reduce mechanical damage to corn kernels by about 64% comparing free fall and about 50% than the use of the cushion box. The amounts of kernels damage increased significantly with increasing drop height and decreasing moisture content, but the use of the cushion box and closed let-down ladder systems somewhat reduced the adverse effect of the above factors.