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Gas chromatographic determination of cadaverine, putrescine, and histamine in foods.

A GLC procedure for the quantitative determination of the diamines putrescine and cadaverine has been developed, using their perfluoropropionyl derivatives. The amines were extracted from foods with methanol; an interval standard, hexanediamine, was added and a dry residue of their hydrochloride salts was prepared. The salts were derivatized with perfluoropropionic anhydride by heating for 30 min at 50 degrees C. The reaction mixture was separated on an alumina column to remove excess reagent, and the derivatives were eluted with a solution of 30% ethyl acetate in toluene. GLC separations were performed on a 3% OV-225 column held at 180 degrees C. The retention times were 4.3, 5.7, and 7.0 min for the derivatives for putrescine, cadaverine, and the internal standard, respectively. Less than 1 microgram diamine/g tissue could be quantitated, using either an electron capture detector or a nitrogen-specific detector. The procedure was applied to cheese and a variety of fishery products. An increase in the diamines correlated with the presence of decomposition in some of the products. A collaborative study of the method is planned.