Extraction of bioactive amines from grated Parmesan cheese using acid, alkaline and organic solvents

Ion-pair-HPLC, post-column derivatization with o-phthalaldehyde and fluorimetric detection is the method of choice for the separation and quantification of bioactive amines in foods. However, there is still no consensus on which methodology is the most appropriate for the extraction of the amines from different food matrices. The efficiency of chloridric, trichloroacetic, perchloric, sulfosalicylic and acetic acids, borate buffer, methanol and ethanol in the extraction of ten bioactive amines from grated Parmesan cheese was investigated. Extraction efficiency was affected by the levels of amines present in the sample and by the type, concentration and temperature of the extractor, and the method used. When selective extraction of amines from grated cheese was desired, the polyamines—spermine and spermidine—were better recovered by HCl; agmatine was better extracted by borate buffer or HCl; the aliphatic amines—putrescine and cadaverine—were more efficiently extracted by borate buffer and HCl; whereas the aromatic amines—tyramine and phenylethylamine—and the indolamines—tryptamine and serotonin—were better recovered with organic solvents. For the adequate extraction of most of the amines from the grated cheese matrix, 1.0 m HCl was chosen, providing good recoveries for most of the amines. Furthermore it is a relatively simple, inexpensive and rapid procedure.