عنوان مقاله [English]
نویسندگان [English]چکیده [English]
As a first step towards mechanization related to any product, including date fruit, it is necessary to have comprehensive information about the product. Physical and mechanical properties are needed for the design of post harvest machinery and equipment. The objective of this study was to determine and compare some physical properties such as dimension, mass and volume, particulate density, pitted density, bulk density, porosity, projected areas, geometric mean diameter, sphericity and surface area of Haj-Ghanbari and Shahani varieties of date fruit. Also coefficient of static friction on three different surfaces including galvanized iron steel, glass and plywood were determined and compared. Experiments for date while pitted dates were carried out at 12.90% and 12.20% (w.b.) moisture content for Haj-¬Ghanbari and 30.55% and 29.42% (w.b.) for Shahani variety. Results indicated that mean mass and volume were 5.57 g and 4.74 g/cm3 for Haj-¬Ghanbari and 8.69 g and 8.67 g/cm3 for Shahani variety. Size and projected areas of Shahani variety were greater than those for Haj-¬Ghanbari. The average fruit true density, pitted density and bulk density of Haj¬-Ghanbari variety were greater than those for than Shahani variety while porosity was less than that for Shahani. The geometric mean diameter, surface area and mean coefficient of static friction of Shahani date were more than those for Haj¬-Ghanbari while sphericity was equal for the two varieties with an average value of 0.58. Results are useful in design of post harvest equipments and machinery for date fruit.