A survey on free biogenic amine content of fresh and preserved vegetables

A survey on free biogenic amine contents in fresh and preserved vegetable products was carried out. A simple extraction method, involving an homogenisation step with 0.1 M HCl, was applied. Two different derivatization procedures (using o-phthaldialdehyde and dansyl chloride) were applied on different aliquots of the same acid extracts and HPLC analyses were carried out with the same reversed phase (C18) HPLC column. Results obtained with the two procedures were compared. With the exception of sauerkraut, putrescine (0.2-0.5 mg/100 g fresh weight) and spermidine (0.4-4.5 mg/100 g) were always the most represented amines, generally followed by spermine (maximum 1.1 mg/100 g). Tyramine level was 4.9 mg/100 g in canned sauerkraut while other samples presented levels not exceeding 1.2 mg/100 g. The spinach sample showed the highest histamine content (2.0 mg/100 g).