Authentication ofCoffea arabicaaccording to Triacylglycerol Stereospecific Composition

Abstract

Stereospecific analysis is an important tool for the characterization of lipid fraction of food products. In the present research, an approach to characterizearabicaandrobustavarieties by structural analysis of the triacylglycerol (TAG) fraction is reported. The lipids were Soxhlet extracted from ground roasted coffee beans with petroleum ether, and the fatty acids (FA) were determined as their corresponding methyl esters. The results of a chemical-enzymatic-chromatographic method were elaborated by a chemometric procedure, Linear Discriminant Analysis (LDA). According to the total and intrapositional FA composition of TAG fraction, the obtained results were able to characterize roasted pure coffee samples and coffee mixtures with 10%robustacoffee added toarabicacoffee. Totally correct classified samples were obtained when the TAG stereospecific results of the considered coffee mixture (90 : 10arabica/robusta) were elaborated by LDA procedure.