Effect of heat treatment during mechanical cracking using varieties of palm nut

Palm nut is characterized with unique physical and mechanical properties which determine performance of machine during cracking.  In this research work, commercially acceptable varieties of palm nut were selected, examined and periodically dried to temperature 120 ℃/h, 135 ℃/h, 150 ℃/h, 165 ℃/h and 180 ℃/h before cracking.  At 120 ℃/h, local, dura and tenera nuts moisture content were found to be: 12.5%, 12.0% and 12.0% respectively; at 135 ℃/h, 11.6%, 11.1% and 11.0% respectively; at 150 ℃/h, 10.7%, 10.2% and 10.0% respectively; at 165 ℃/h, 10.3%, 9.6% and 9.1% respectively; and at 180 ℃/h, 9.8%, 9.0% and 8.2% respectively. An improved automated palm nut cracker of 2004 model was used for the experiment and results shown that the highest throughput, functional efficiency and quality performance efficiency were  1,260 kg/h, 99.07% and 98.80% respectively while mechanical damage reduced to 0.20%.  Simple multiple linear regression model was used to establish the relation between machine and crop parameters. Keywords: drying, efficiency, cracker, effect, varieties, palm nut &nbsp