The thermal degradation of oils and fats leads to the formation of polar compounds, which is the reason why their determination is adopted for the quality control of the oil and fat used in flying. Samples of refined and partially hydrogenated soybean oil were heated for 30 and 60 hours respectively, and the polar compounds content were determined using the IUPAC-AOAC official method and TLC-FID. The samples of oil and the fractions separated on the column were applied to the chromarods and developed in petroleum ether: diethyl ether (93:7 v/v). The determination of polar compounds by IUPAC method and by TLC-FID presented similar results (P-value<<0,001), although when the content was greater than 16% the second method gave higher values. The results showed that the state of degradation of oils and fats as measured for the quantity of polar compounds can be determined alternatively by TLC-FID, presenting a significant reduction in time, hand work and solvent volume.483148153