Some Physical & Mechanical properties of Marking Nut and Kernel

Marking nut or 'SemecarpusAnacardium L.' also known as 'bibba' or 'bhilawa'. Marking nut has a double walled shell and cracking shells yields toxic resin (Bhilawan shell liquid) & enclosed dry kernel. Present study objective is to determine design parameters of marking nut & kernel for development of efficient marking nut deshelling machine. Xrays images of nuts by AGFA Image processing software of 100 marking nuts show tremendous variation in shape & size of nut & kernel. Sphericity, bulk density, thousand nut mass were found in range of 0.92 to 0.79, 572.22 to 528.48 kg/m3 , 2015.40 to 3365 grams & corresponding values for Kernel 0.63 to 0.67, 540 to 478.62 Kg/m3 , 232 to 410 grams. Average shell thickness was found to be 3.5mm. For marking nuts at 12% moisture (d.b) Hardness & deformation was found 87.64N & 3.20mm, at 9.63% moisture (d.b) 93.98N & 2.50mm, at 4.86% moisture 118N & 0.65mm, respectively. Rupture force for nuts by compression was found to be in range of 23.21Kg to 37.34Kg. Texture profile analysis of kernel was performed at 3.02% moisture (d.b) & Hardness was found to be 19.98N at cycle-1, 17.77N at cycle-2, this shows kernel is delicate then the nut & easily cracked at lower forces. Springiness & cohesiveness were determined and found to be 0.62 & 0.53, respectively.