Determination of biogenic amines in cheese using HPLC technique and direct derivatization of acid extract

Cheeses are among those high-protein-containing foodstuffs in which enzymatic and microbial activities cause the formation of biogenic amines from amino acids decarboxylation. Most of the methods for amine determination in this products involve acid extraction followed by a liquid–liquid purification step to selectively separate amines and amino acids. In this work a simple direct derivatization of the acidic extract with dansyl chloride (DCl) was applied. After an extraction step with diethyl ether, the amines were separated on a Kromasil C18 column using a water–acetonitrile elution gradient. Taking into consideration the recovery and repeatability data we can conclude that, when free amino acid determination is not of concern, the direct DCl derivatization procedure can be applied also for cheese samples with high free amino acid contents.