Department of Agrotechnology, University of Tehran, College of Aburaihan, Tehran, Iran
Removing the green husk and drying walnut are one of the most important steps in post-harvest processing of walnut. Therefore, it is need to precisely identify a walnut’s shell. Physical and mechanical properties of shell in the four Persian walnut cultivars/genotypes were studied. This study investigated the mechanical properties of a walnut’s husk and calculated the required energy in the process of shearing, penetrating and bruising for four walnut cultivars/genotypes (K72, Z67, Pedro, Serr). This was done by a texture analyzer instrument. Required energy to perform each of these tests were given in terms of the maximum and minimum values. The averaged results were so that the maximum amount of Krammer shear test belonged to K72 variety and the minimum of that belonged to Pedro variety. Penetration’s test data also indicated that the maximum amount in four available varieties was Pedro and the minimum value was suitable for Z76. Also, in the bruising test, Serr variety had the maximum value of required energy and Z76 variety had the minimum energy requirement.