Moisture Dependent Geometric and Mechanical Properties of Wild Pistachio (Pistacia vera L.) Nut and Kernel

In this research, wild pistachio (Pistacia vera L.) nuts and kernels were analyzed for selected geometric properties and mechanical behavior under compression loading. The average length, width and thickness arithmetic and geometric mean diameter of wild pistachio nuts at 5.83% w.b. were 13.98, 8.76, 7.25, 9.93, and 9.75 mm, while the corresponding values of kernels at 6.03% w.b. moisture content were 11.07, 5.92, 4.83, 7.21, and 6.88 mm, respectively. As the moisture content of pistachio nut increased from 5.83 to 30.73% w.b., the bulk density, apparent density and terminal velocity were found to increase from 521 to 543 kgm −3 , 809 to 829 kgm −3 , and 5.51 to 6.29 ms −1 , respectively, whereas porosity decreased from 35.14% to 34.63%. The results revealed that wild pistachio nut required higher rupture force and energy to crack wild pistachio nuts for compression along the L-axis as compared to other two axes.