Study On The Extraction Of Jatropha Seed Oil And Its Oxidative Stability Researches

This experiment used Jatropha curcas L. from Pan Zhihua province as material,by optimizing the Screw-Pressing process and Supercritical CO2 extraction process of Jatropha seed oil,and comparing Screw-Pressing with Supercritical CO2 extraction distilling on Jatropha seed oil,then analysing the chemical compositions of Jatropha seed oil,doing research on preservation and anti-oxidation experiment of Jatropha seed oil.The experiment provided basis for the deep processing and full use of Jatropha seed.The main results of this study were as follows.1 This experiment analysed the chemical compositions of Jatropha seed.The results showed water 5.07%,fat 56.60%,protein 19.98%,ash 4.37%.2 Optimizing Screw-Pressing process of Jatropha seed oil.The optimal conditions of Screw-Pressing process werewater content 3%,nutlet shell ratio 8:2,pressing temperature 170℃,temperature of the material 100℃.In optimal conditions,the extraction yield was 87.90%.3 The extracting technology of Jatropha seed oil by supercritical CO2 was studied.Some factors which influenced oil yield were analysed by single factor trial.The optimal conditions were particle size 20 screen mesh,extracting time 120 min,modifier 40%of the material.Taking the extraction pressure,extraction temperature and CO2 flow rate as the variables of Box-Behnken Design,the results of response surface analysis(RSA) showed that the optimum parameters of SEF were:extraction pressure 37MPa,extraction temperature 44.5℃,CO2 flow rate 30L/h.In optimal conditions,the extraction yield was 93.13%.4 Compared the quality of oil extracted by SEF technique and Screw-Pressing.It showed that the quality of Jatropha seed oil distilled by supercritical CO2 was superior to the one distilled by Screw-Pressing.5 Using GC to identify fatty acid compositions of Jatropha seed oil extracted by SEF technique and Screw-Pressing.It showed that there were little differences between the fatty acid composition of Jatropha seed oil by SEF technique and Screw-Pressing.The content of unsaturated fatty acid was over 70%.6 The oxidation stability experiments of the oil extracted by SEF technique and Screw-Pressing process showed that the oil extracted by SEF technique is much more oxidable compared with the pressed oil.7 The Antioxidant capacity of the three antioxidants with the addition of both 0.02% showed as the follow order:TBHQ> BHT> VE.