Detection of pork and lard as adulterants in processed meat: liquid chromatographic analysis of derivatized triglycerides.

A new method is described for detection of pork and lard as adulterants in processed beef and mutton mixtures. The unsaturated triglycerides in the fat are ozonized and then derivatized. The mixture of derivatized and saturated triglycerides is analyzed by liquid chromatography using a reverse-phase column and a UV detector. Pork fat has larger amounts of triglyceride containing saturated fatty acid at the C-2 position than does the fat of other meat. The ratio of triglyceride containing saturated fatty acid vs triglyceride containing unsaturated fatty acid at the same (C-2) position (SSU/SUS) in a sample is compared with those of pure meats. The presence of pork in the sample causes the ratio to increase compared with ratios for pure beef or mutton. The increase in the SSU/SUS ratio is significant for the addition of 1% pork in beef. In the case of mutton, the addition of 3% pork causes a noticeable change. The method is reliable and is also applicable to samples containing only fat. Processing (heating or cooking) does not affect the ratios.