Effect of Some Sorting-Related Parameters on the Area and Volume Bruising of “Golden Delicious” Apple

Apple fruits are subjected to different loading from harvesting to supermarket shelf. Bruising has been attracted by many researchers as one of the most important damage criterian. In the present research, the effects of some factors such as counter-face material, drop height and linear velocity of apples (conveyor speed) 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), conveyor speed (0.05, 0.1 and 0.15 ms⁻¹) and four counter-face materials (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 counter-face material on bruising area at 1% level was significant while bruising volume only affected by contact surface material (P<0.01). Mean comparison test indicated that there was no significant difference between levels of convey or speed on the area and volume bruising. Also, there was no significant difference between levels of drop height on volume bruising while it was significant on the area bruising. Steel and wooden material had no significant effect on the area and volume bruising but their differences with plastic and cardboard were significant. Therefore, drop height and counter-face material must be considered in designing the apple processing systems.