A SIMPLE PROCEDURE TO EVALUATE THE PERFORMANCE OF FATS AND OILS AT FRYING TEMPERATURES

A standard procedure is proposed to evaluate the performance of fats a nd oils at frying temperatures, taking the advantages provided by the Rancimat apparatus, i. e., standard vessels, temperature correction an d temperature homogenity in all vessels resulting from the particular characteristics of the heating block. The results obtained in oil samp les of 8 g heated at 180 degrees C for 10 h in triplicate gave coeffic ients of variation lower than 6% for total polar compounds and polymer s. In case of limited amount of oil, it is additionally proposed to us e only 2 g of sample provided that a similar surface-to-oil volume rat io 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 o ils are included. As an example, the effect of alpha-tocopherol on per formance of sunflower oils was analyzed.