Heat treatment of Jatropha curcas L. seeds under compression loading

Using the compression device ZDM 50-2313/56/18 with a chart recorder, pressing vessel of diameter 60 mm and a plunger, the effect of heat treatment temperature on Jatropha curcas L. seeds was investigated where parameters including compressive force (N), seed deformation (mm), deformation energy (J) and seed hardness (N/mm) were determined. Before the experiment, the jatropha seeds were cleaned from all foreign matter and were grouped into five different samples. These samples were pre-heated at temperature levels from 75, 85, 95, 105 and 115 ˚C, respectively, at pre-heating time 30 minutes constant and each sample was replicated three times where average values were used in all calculations. Statistical analysis at 0.05 significant level showed that pre-heating temperatures of the jatropha seeds before compression increased seed deformation (mm), deformation energy (J) and compressive force (N). Contrary, seed hardness (N/mm) decreased in relation to the effect of pre-heating temperatures. Polynomial function best described all the measured dependencies. The study indicated that heattreatment temperature could influence the mechanical behaviour of Jatropha curcas L. seeds under compression loading