Free and conjugated biogenic amines in green and roasted coffee beans

This work reports the composition of arabica and robusta coffees in terms of biogenic amines. The analyses were conducted before and after acid hydrolysis with the aim of the determining both free and conjugated forms in green and roasted coffee beans. The amines (putrescine, cadaverine, serotonin, tyramine, spermidine, and spermine) were determined by reverse-phase high-performance liquid chromatography (RP-HPLC) after derivatization with dansyl chloride. Multivariate analyses were applied in order to evaluate the possible use of these amines as chemical descriptors for arabica and robusta coffees. It was found that putrescine, the main biogenic amine present in the green beans, could be used in the discrimination of the referred species. There is also some evidence that these compounds can be used for discrimination between green coffees subjected to different postharvest processes and that tyramine can be considered a chemical marker for Angolan robustas. The variations in biogenic amine levels after roasts is also discussed, but the statistical significance for species discrimination is reduced.