A standard procedure is proposed to evaluate the performance of fats and oils at frying temperatures, taking the advantages provided by the Rancimat apparatus, i. e., standard vessels, temperature correction and temperature homogenity in all vessels resulting from the particular characteristics of the heating block. The results obtained in oil samples of 8 g heated at 180 degrees C for 10 h in triplicate gave coefficients of variation lower than 6% for total polar compounds and polymers. In case of limited amount of oil, it is additionally proposed to use only 2 g of sample provided that a similar surface-to-oil volume ratio is maintained, and coefficients of variation of the same order than those for 8 g samples were thus obtained. Advantages of the procedure as well as potential applications for evaluation of frying fats and oils are included. As an example, the effect of alpha-tocopherol on performance of sunflower oils was analyzed.484231235