Fried foods are frequently served by fast food establishments but the evaluation of the oil used is quite laborious, expensive, and requires a well-structured laboratory with sophisticated equipment. Moreover, p-anisidine, used as the reagent in the traditional test for monitoring the alkenal concentration of frying oils, is carcinogenic. The DiaMed F.A.T.S. kits for the determination of alkenal (AlkalSafe (TM) STD) and malonaldehyde (AldelSafe (TM) STD), equivalent to the p-anisidine and TBA tests, respectively, are safe, fast and accurate, using compact equipment and generating fewer residues than the official methods. The results obtained using these kits were compared with those obtained using the official methods for determining alkenal (AOCS Cd 18b-90) and malonaldehyde (AOCS Cd 19b-90), in 20 samples collected from an institutional restaurant. Based on the least squares regression analysis, the AlkalSafe kit results were highly correlated with the p-anisidine values (r = 0.74), but there was a lack of correlation between the results of the AldeSafe (TM) kit and the TBA test. Both kits were significantly more sensitive than the official methods, as revealed by the results of the Tukey test. Although the TBA values for the samples investigated were minimal, suggesting the inadequacy of the test for monitoring frying oils, the greater sensitivity of the kit makes it a relatively feasible option.8410893897