The Effects of Drop Height, Conveyor Velocity and Contact Surface Material on Area and Volume Bruising of " Golden Delicious" Apple

Apple fruits are subjected to different loading from harvesting to supermarket shelf. Bruising has been attracted many researchers as one of the most important damage criteria. In this research, the effects of some factors such as contact surface material, drop height and linear velocity of apples were investigated. Influence of these factors on bruising of “Golden Delicious” variety was analyzed by a Completely Randomized Design (CRD) with factorial test at three level of drop height (10, 20 and 30 cm), linear velocity (0.05, 0.1 and 0.15 ms-1) and four contact surface (wooden, steel, plastic and cardboard). Tests were conducted at three replications with 108 treatments. Analysis of variance results showed that the effects of drop height and contact surface material on bruising area at 1% level was significant while bruising volume only affected by contact surface material (meaningful difference at 1% level). Mean comparison test indicated that there significant difference between levels of drop height on the bruise area. Also, there was a meaningful difference between contact surface of cardboard with steel, wood and plastic. There was a significant difference between surface materials of steel and wooden with cardboard and plastic. Therefore, drop height and contact surface material must be considered in designing the apple processing systems.