Cresol Isomers Contaminating Beef on the Market

An analytical procedure for three cresol isomers (o-, p-, and m-isomers) contaminating beef was developed. Isolation of the compounds from the beef was efficiently carried out by steam distillation which was followed by liquid-liquid partition of the distillate with diethyl ether. The extracts were analyzed by gas chromatography (GC) in combination with capillary GC-mass spectrometry. The three isomers were all detected in a sample of ground beef and in hamburger containing that beef. The concentrations of o-, p- and m- cresol in the beef were 1.7, 7.9 and 17.9 ppm, respectively. Though the concentration of each cresol isomer in the hamburger was slightly less than that in the ground beef, the ratio of each isomer in the hamburger was the same as that in the beef. The cresol isomers were not detected in five other beef samples on the market. The detection limit of each isomer was 0.2 ppm.