Liquid chromatographic determination of some amines and their amino acid precursors in protein foods.

A quantitative assay has been developed for putrescine, cadaverine, histamine, and several free amino acids--lysine, arginine, and histidine--as a measure of decomposition. The free amines and amino acids are extracted from tissue with methanol. Aliquots of the extracts are passed through ion-exchange columns which are pH-adjusted to retain the cited compounds. After the respective columns are washed, the amino acids and amines are eluted, dansylated, and chromatographed on a suitably prepared LC instrument. The chromatographic responses for the amino acids and amines are compared with their respective standards to determine their concentrations. Validation of the methodology includes standard addition and calibration experiments.