Pressing extraction and physico-chemical characterization of seed oil and cake of Jatropha curcas L.

Abstract

Fuel from renewable sources has been an excellent alternative to mineral diesel fuel, either as a substitute or an additive, after the transformation process of oil into biodiesel. Jatropha (Jatropha curcas L.) is considered a good option since it produces high-quality oil. The aim of this study was to evaluate the quality parameters of samples of physic nut oil processed at different temperatures, as well as to characterize the byproduct press (seed and cake). For this purpose, we evaluated several properties of the oil including acid index, saponification, peroxides, humidity, index of impurities insoluble in ether, ash content, relative density, refractive index, Kreis reaction, color, and mineral content. We also evaluated several properties of the grains and press cake including humidity, ash content, protein content, lipids, fibers, carbohydrates, and minerals. A completely randomized design was used to achieve the results, with three extraction temperatures (70°C, 90°C, and 110°C). Descriptive analysis, normality, analysis of variance, and Tukey's means comparison test were employed at a 5% significance level. Pearson's linear correlation coefficient was also applied. The extraction temperature of 90°C resulted in significant changes in the physical-chemical properties of the oil and press cake.