The influence of storage conditions on the properties of biodiesel from macaúba (Acrocomia aculeata (Jacq.) Lodd. ex Mart). seed oil was evaluated. The biodiesel samples were stored for 12 months at 25 °C and 4 °C. The physical properties of the biodiesel: acidity index, peroxide and refractive index, flash point, and oxidative stability were determined. The chemical composition of the biodiesel was determined by gas chromatography coupled to mass spectrometry and by infrared spectroscopy. The analysis of the main components and the Hierarchical Analysis were used to group the samples. The oxidative stability of biodiesel, which developed low acid and peroxide indexes, and the ester composition were maintained stable, regardless of the storage method. However, storage at 4 °C proved to be more efficient in maintaining the characteristics of the biodiesel. The high quality of biodiesel and its stability confirm the potential of the agro-industrial use of biodiesel from Acrocomia aculeata.

Vegetables oils are renewables sources of ready availability with vast commercial employability. The application of these oils, generally, requires refining procedures for the removal of substances that make it unfeasible, such as phosphatides, proteins and free fatty acids. The objective of this study was to evaluate the effect of acid and aqueous degumming on the physical-chemical properties of crude oil of Mauritia flexuosa L.f. (buriti), palm tree of the family Arecaceae, very commercially exploited and well adapted to the Cerrado biome. Physical and chemical analysis were performed as acidity index, peroxide index, refraction, viscosity, density, gas chromatography coupled to the mass spectrometer and infrared spectroscopy before and after the refining process. The acidity, density and refraction indices didn´t change significantly during the treatments; however, significant differences were observed for the peroxide and viscosity parameters after the acid degumming process. Chromatographic and infrared spectroscopy results didn´t reveal changes in the constitution of constituent esters. The acid degumming was more efficient for the removal of undesirable substances, with significant variation (p < 0.05) for the peroxide index after this process. However, M. flexuosa oil presented good stability, keeping indexes acceptable in view of the current resolutions for its use.