Comparison of Some Physico-Mechanical Nut and Kernel Properties of Two Walnut (Juglans regia L.) Cultivars

Some physical such as length, width, thickness, mass, geometric mean diameter, sphericity and surface area and mechanical properties such as deformation at cracking, cracking force, energy absorbed and hardness of nuts and kernels were determined at three orientations first time for two walnut cultivars, namely Mara?-18 and Yalova-1 widely grown in Turkey. For nuts, the average length (45.48 mm), mass (12.70 g), geometric mean diameter (36.83 mm) and surface area (42.66 cm2) were the highest in cv. Yalova-1 while width (34.18 mm), thickness (33.74 mm), shell thickness (1.48 mm) and sphericity (87.41%) were the highest in cv. Mara?-18. For all the loading orientations, the values of deformation at cracking, cracking force, energy absorbed and hardness of cv. Mara?-18 were higher than those of cv. Yalova-1. The effect of loading orientation to kernel extraction quality was found insignificant for both walnut cultivars.