Estudo da degradação da vitamina E (a-tocoferol) durante as etapas do refino do óleo de babaçu (Orbignya phalerata, Mart.): validação de um método

Abstract

Due to its territorial location and the sort of oily plant adapted to its clamate, Maranhão has a vast agricultural potential for producing vegetable oil and their bioderivates. Among them is the babassu palm (Orbignya pharlerata, Mart.), a vegetal rich in oil that is composed by 95% of triglycerides and traces of tocopherols. Such tocopherols act as antioxidative agents that prevent the degradation of unsaturated fatty acids of vegetal oils. Therefore, several methods have being proposed for quantifying these natural antioxidants in both oil and bioderivate products; however, they often require long time of analysis and a pretreatment of the sample. Thus, this paper aims to propose an alternative method for quantifing a-tocopherol in babassu oil, as well as, evaluating its degradation during the oil refining (industrial and laboratorial scales) by mean of high performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FTIR). Hence, no previous sample treatments were performed, being the sample only diluted in 2-propanol (HPLC) or chloroform (FTIR) solvents. The use of the spectroscopy technique was rather limited, once it was incapable of distinguish between the tocopherols and/or tocotrienols (β, γ and δ) presented in the media. Conversely, the developed chromatographic method provided an efficient separation of such compounds, yielding in a significant sensibility and good linearity, precision and accuracy of the results.