The determination of fatty acids (FA) in liver from three different groups of Wistar rats (six rats by group) submitted to diet (AIN-93G) by capillary zone electrophoresis (CZE) was proposed. Each group received the same diet. However, the soybean oil used to prepare the feed, whose amount was 7% w/w, had different origins. The first group was fed with feed containing soybean oil fresh; the second one was fed with soybean used during 7 days in deep frying process; finally, the third was fed with soybean used during 15 days in deep frying process. After 45 days the rats were submitted to euthanasia and the FA amount in liver was successful monitored by CZE in a simple, fast and efficient way. The results obtained were compared to gas chromatography official method and no significant differences were observed within 95% confidence interval. The electropherograms to FA analysis were submitted to principal component analysis (PCA) being possible to discriminate the final from the control and intermediate groups. In addition to PCA results, the low density lipoprotein (LDL) was evaluated indicating that the total time exposure of the oil submitted to deep frying processes can be considered relevant to evaluating the oil quality.
fatty acids; liver rat; capillary zone electrophoresis; gas chromatography; chemometric
